View source for Philae (spacecraft)

{{Short description|Robotic European Space Agency lander that accompanied the Rosetta spacecraft}}
{{Use dmy dates|date=November 2022}}
{{Use British English|date=November 2014}}
{{DISPLAYTITLE:''Philae'' (spacecraft)}}
{{Infobox spaceflight
| name                  = ''Philae''

<!--image of the spacecraft/mission-->
| image                 = Philae lander (transparent bg).png
| image_caption         = Illustration of ''Philae''
| image_alt             =
| image_size            = 300px

<!--mission insignia or patch-->
| insignia              = <!--omit the "file" prefix-->
| insignia_caption      = <!--image caption-->
| insignia_alt          = <!--image alt text-->

<!--Basic details-->
| mission_type          = [[Comet]] [[lander (spacecraft)|lander]]
| operator              = [[European Space Agency]]{{\}}[[German Aerospace Center|DLR]]
| website               = {{URL|http://www.esa.int/rosetta}}
| COSPAR_ID             = 2004-006C
| mission_duration      = Planned: 1–6 weeks<br />Active: 12–14 November 2014<br />Hibernation: 15 November 2014 – 13 June 2015

<!--Spacecraft properties-->
| manufacturer          = [[CNES]]<br>[[German Aerospace Center|DLR]]<br>[[Italian Space Agency|ASI]]
| dry_mass              = <!--spacecraft mass in orbit without fuel-->
| launch_mass           = {{convert|100|kg|lb|abbr=on}}<ref name="nssdc">{{Cite web |title=Philae |url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2004-006C |url-status=live |archive-url=https://web.archive.org/web/20231205185354/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2004-006C |archive-date=5 December 2023 |access-date=18 November 2014 |publisher=[[National Space Science Data Center]] |id=2004-006C }}</ref>
| payload_mass          = {{convert|21|kg|lb|abbr=on}}<ref name=nssdc />
| dimensions            = {{convert|1|xx|1|xx|0.8|m|ft|abbr=on}}<ref name="nssdc" />
| power                 = 32 watts at 3 [[Astronomical unit|AU]]<ref name="dlrPdf">{{Cite web |title=Philae lander fact sheets |url=https://www.dlr.de/dlr/Portaldata/1/Resources/documents/Philae_Lander_FactSheets.pdf |url-status=live |archive-url=https://web.archive.org/web/20221122103836/https://www.dlr.de/dlr/Portaldata/1/Resources/documents/Philae_Lander_FactSheets.pdf |archive-date=22 November 2022 |access-date=28 January 2014 |publisher=[[German Aerospace Center]] }}</ref>

<!--Launch details-->
| launch_date           = {{start-date|2 March 2004, 07:17}}&nbsp;UTC
| launch_rocket         = [[Ariane 5|Ariane 5G+]] V-158
| launch_site           = [[Guiana Space Centre|Kourou]] [[ELA-3]]
| launch_contractor     = [[Arianespace]]

<!--end of mission-->
| last_contact          = {{end-date|9 July 2015, 18:07}}&nbsp;UTC

|interplanetary         = <!-- Infobox spaceflight/IP can be called multiple times for missions with multiple targets or combined orbiter/lander missions, etc-->
 {{Infobox spaceflight/IP
   |type                = lander
   |object              = [[67P/Churyumov–Gerasimenko]]
   |arrival_date        = 12 November 2014, 17:32&nbsp;UTC<ref name="esathree20141114">{{Cite press release |date=14 November 2014 |title=Three Touchdowns For Rosetta's Lander |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Three_touchdowns_for_Rosetta_s_lander |url-status=live |archive-url=https://web.archive.org/web/20231018072901/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Three_touchdowns_for_Rosetta_s_lander |archive-date=18 October 2023 |access-date=15 November 2014 |publisher=[[European Space Agency]] }}</ref>
   |location            = Abydos<ref name="Philaefound">{{Cite press release |date=5 September 2016 |title=Philae found! |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Philae_found |url-status=live |archive-url=https://web.archive.org/web/20240116104049/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Philae_found |archive-date=16 January 2024 |access-date=5 September 2016 |publisher=[[European Space Agency]] }}</ref>
 }}

| instruments_list      =<!-- start collapsible list -->
  {{Infobox spaceflight/Instruments
   |acronym1 =[[APXS]]   |name1=Alpha particle x-ray spectrometer
   |acronym2 =CIVA       |name2=Comet nucleus Infrared and Visible Analyser
   |acronym3 =[[CONSERT]]|name3=Comet Nucleus Sounding Experiment by Radiowave Transmission
   |acronym4 =COSAC      |name4=Cometary Sampling and Composition
   |acronym5 =MUPUS      |name5=Multi-purpose Sensors for Surface and Subsurface Science
   |acronym6 =PTOLEMY    |name6=Gas chromatograph and medium resolution mass spectrometer
   |acronym7 =ROLIS      |name7=Rosetta Lander Imaging System
   |acronym8 =ROMAP      |name8= Rosetta lander Magnetometer and Plasma monitor
   |acronym9 =SD2        |name9=Sampling, Drilling and Distribution
   |acronym10=SESAME     |name10=Surface Electric Sounding and Acoustic Monitoring Experiment<ref name="esa-ros-instruments">{{Cite web |title=Lander Instruments |url=https://sci.esa.int/web/rosetta/-/31445-instruments |url-status=live |archive-url=https://web.archive.org/web/20231225002314/https://sci.esa.int/web/rosetta/-/31445-instruments |archive-date=25 December 2023 |access-date=3 March 2015 |publisher=[[European Space Agency]] }}</ref>
   |acronym11=CASSE      |name11=Comet Acoustic Surface Sounding Experiment
   |acronym12=DIM        |name12=Dust Impact Monitor
   |acronym13=PP         |name13=Permittivity Probe
  }}<!-- end collapsible list -->
}}<!-- end infobox -->

'''''Philae''''' ({{IPAc-en|'|f|aɪ|l|iː}}<ref name="dict-com-philae">{{Cite encyclopedia |title=philae |encyclopedia=Dictionary.com Unabridged |publisher=Random House |url=https://www.dictionary.com/browse/philae |access-date=13 November 2014 |archive-url=https://web.archive.org/web/20231112155439/https://www.dictionary.com/browse/philae |archive-date=12 November 2023 |url-status=live }}</ref> or {{IPAc-en|'|f|i:|l|eɪ}}<ref name="cnn-20141112">{{Cite news |last=Gilbert |first=Dave |date=12 November 2014 |title=Space probe scores a 310-million-mile bull's-eye with comet landing |url=https://edition.cnn.com/2014/11/12/world/comet-landing-countdown/index.html |url-status=live |archive-url=https://web.archive.org/web/20240104233734/https://edition.cnn.com/2014/11/12/world/comet-landing-countdown/index.html |archive-date=4 January 2024 |access-date=13 November 2014 |work=[[CNN]] }}</ref>) was a [[robotic]] [[European Space Agency]] [[Lander (spacecraft)|lander]] that accompanied the [[Rosetta (spacecraft)|''Rosetta'']] [[spacecraft]]<ref name="NYT-20140805">{{Cite news |last=Chang |first=Kenneth |date=5 August 2014 |title=Rosetta Spacecraft Set for Unprecedented Close Study of a Comet |url=https://www.nytimes.com/2014/08/06/science/space/rosetta-spacecraft-set-for-unprecedented-close-study-of-a-comet.html |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20230807111121/https://www.nytimes.com/2014/08/06/science/space/rosetta-spacecraft-set-for-unprecedented-close-study-of-a-comet.html |archive-date=7 August 2023 |access-date=5 August 2014 |work=[[The New York Times]] }}</ref><ref name="NYT-20141123-ED">{{Cite news |date=23 November 2014 |title=Opinion: In Pursuit of an Oddly Shaped Comet |url=https://www.nytimes.com/2014/11/24/opinion/in-pursuit-of-an-oddly-shaped-comet.html |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20231112155439/https://www.nytimes.com/2014/11/24/opinion/in-pursuit-of-an-oddly-shaped-comet.html |archive-date=12 November 2023 |access-date=23 November 2014 |work=[[The New York Times]] }}</ref> until it separated to land on [[comet]] [[67P/Churyumov–Gerasimenko]], ten years and eight months after departing Earth.<ref name="UlamecActa">{{Cite journal |last1=Ulamec |first1=S. |last2=Espinasse |first2=S. |last3=Feuerbacher |first3=B. |last4=Hilchenbach |first4=M. |last5=Moura |first5=D. |last6=Rosenbauer |first6=H. |last7=Scheuerle |first7=H. |last8=Willnecker |first8=R. |display-authors=5 |date=April 2006 |title=Rosetta Lander—Philae: Implications of an alternative mission |journal=[[Acta Astronautica]] |volume=58 |issue=8 |pages=435–441 |bibcode=2006AcAau..58..435U |doi=10.1016/j.actaastro.2005.12.009 }}</ref><ref name="Biele2002">{{Cite journal |last=Biele |first=Jens |date=June 2002 |title=The Experiments Onboard the ROSETTA Lander |journal=Earth, Moon, and Planets |volume=90 |issue=1–4 |pages=445–458 |bibcode=2002EM&P...90..445B |doi=10.1023/A:1021523227314 |s2cid=189900125 }}</ref><ref name="NASA-201401017">{{Cite press release |last1=Agle |first1=D. C. |last2=Cook |first2=Jia-Rui |last3=Brown |first3=Dwayne |last4=Bauer |first4=Markus |date=17 January 2014 |title=Rosetta: To Chase a Comet |url=https://www.jpl.nasa.gov/news/rosetta-to-chase-a-comet |url-status=live |archive-url=https://web.archive.org/web/20231112083043/https://www.jpl.nasa.gov/news/rosetta-to-chase-a-comet |archive-date=12 November 2023 |access-date=18 January 2014 |publisher=[[NASA]] }}</ref> On 12 November 2014, ''Philae'' touched down on the comet, but it bounced when its anchoring harpoons failed to deploy and a thruster designed to hold the probe to the surface did not fire.<ref name="newsciprob20141113" />  After bouncing off the surface twice, ''Philae'' achieved the first-ever "soft" (nondestructive) landing on a [[comet nucleus]],<ref name="NASA-20141112-DCA">{{Cite press release |last1=Agle |first1=D. C. |last2=Webster |first2=Guy |last3=Brown |first3=Dwayne |last4=Bauer |first4=Markus |date=12 November 2014 |title=Rosetta's 'Philae' Makes Historic First Landing on a Comet |url=https://www.jpl.nasa.gov/news/rosettas-philae-makes-historic-first-landing-on-a-comet |url-status=live |archive-url=https://web.archive.org/web/20231216135840/https://www.jpl.nasa.gov/news/rosettas-philae-makes-historic-first-landing-on-a-comet |archive-date=16 December 2023 |access-date=13 November 2014 |publisher=[[NASA]] }}</ref><ref name="NYT-20141112-KC">{{Cite news |last=Chang |first=Kenneth |date=12 November 2014 |title=European Space Agency's Spacecraft Lands on Comet's Surface |url=https://www.nytimes.com/2014/11/13/science/space/european-space-agencys-spacecraft-lands-on-comets-surface.html |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20231112094834/https://www.nytimes.com/2014/11/13/science/space/european-space-agencys-spacecraft-lands-on-comets-surface.html |archive-date=12 November 2023 |access-date=12 November 2014 |work=[[The New York Times]] }}</ref><ref name="PhilaeInd1">{{cite news |url=https://www.independent.co.uk/news/science/philae-lander-bounced-twice-on-comet-and-may-still-not-be-stable-rosetta-mission-scientists-warn-9857551.html |archive-url=https://ghostarchive.org/archive/20220526/https://www.independent.co.uk/news/science/philae-lander-bounced-twice-on-comet-and-may-still-not-be-stable-rosetta-mission-scientists-warn-9857551.html |archive-date=26 May 2022 |url-access=subscription |url-status=live |title=Philae lander 'bounced twice' on comet but is now stable, Rosetta mission scientists confirm |work=[[The Independent]] |last=Withnall |first=Adam |date=13 November 2014 |access-date=5 September 2016}}</ref> although the lander's final, uncontrolled touchdown left it in a non-optimal location and orientation.<ref name="PhilaeBBC1">{{Cite news |last=Amos |first=Jonathan |date=13 November 2014 |title=Rosetta: Battery will limit life of Philae comet lander |url=https://www.bbc.com/news/science-environment-30034060 |url-status=live |archive-url=https://web.archive.org/web/20240211141611/https://www.bbc.com/news/science-environment-30034060 |archive-date=11 February 2024 |access-date=5 September 2016 |work=[[BBC News]] }}</ref>

Despite the landing problems, the probe's instruments obtained the first images from a comet's surface.<ref name="esa20140116">{{Cite news |date=16 January 2014 |title=Europe's comet chaser |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Europe_s_comet_chaser |url-status=live |archive-url=https://web.archive.org/web/20231218053956/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Europe_s_comet_chaser |archive-date=18 December 2023 |access-date=5 August 2014 |publisher=[[European Space Agency]] }}</ref>  Several of the instruments on ''Philae'' made the first in-situ analysis of a comet nucleus, sending back data regarding the composition of the surface and outgassing from the subsurface.<ref name="esa-20141115">{{Cite press release |date=15 November 2014 |title=Pioneering Philae completes main mission before hibernation |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Pioneering_Philae_completes_main_mission_before_hibernation |url-status=live |archive-url=https://web.archive.org/web/20240109021920/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Pioneering_Philae_completes_main_mission_before_hibernation |archive-date=9 January 2024 |access-date=3 March 2015 |publisher=[[European Space Agency]] }}</ref> In October 2020, scientific journal ''[[Nature (journal)|Nature]]'' published an article revealing what ''Philae'' had discovered while it was operational on the surface of 67P/Churyumov–Gerasimenko.<ref name="reportsofdiscovery">{{Cite journal |last1=O'Rourke |first1=Laurence |last2=Heinisch |first2=Philip |last3=Sierks |first3=Holger |date=28 October 2020 |title=The Philae lander reveals low-strength primitive ice inside cometary boulders |url=https://elib.dlr.de/137009/1/s41586-020-2834-3.pdf |url-status=live |journal=[[Nature (journal)|Nature]] |volume=586 |issue=7831 |pages=697–701 |bibcode=2020Natur.586..697O |doi=10.1038/s41586-020-2834-3 |pmid=33116289 |s2cid=226044338 |archive-url=https://web.archive.org/web/20231220065125/https://elib.dlr.de/137009/1/s41586-020-2834-3.pdf |archive-date=20 December 2023 |access-date=26 April 2021 }}</ref>

On 15 November 2014 ''Philae'' entered [[Safe mode (spacecraft)|safe mode]], or hibernation, after its batteries ran down due to reduced sunlight and an off-nominal spacecraft orientation at the crash site.  Mission controllers hoped that additional sunlight on the solar panels might be sufficient to reboot the lander.<ref name="CNN-20141118">{{Cite news |last1=Brumfield |first1=Ben |last2=Carter |first2=Chelsea J. |date=18 November 2014 |title=On a comet 10 years away, Philae conks out, maybe for good |url=https://edition.cnn.com/2014/11/14/world/comet-landing/ |url-status=live |archive-url=https://web.archive.org/web/20230322100554/http://edition.cnn.com/2014/11/14/world/comet-landing/ |archive-date=22 March 2023 |access-date=28 December 2014 |work=[[CNN]] }}</ref> ''Philae'' communicated sporadically with ''Rosetta'' from 13 June to 9 July 2015,<ref name="NAT-20150614">{{Cite journal |last1=Biever |first1=Celeste |last2=Gibney |first2=Elizabeth |date=14 June 2015 |title=Philae comet lander wakes up and phones home |url=https://www.nature.com/articles/nature.2015.17756.pdf |url-status=live |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature.2015.17756 |s2cid=182262028 |archive-url=https://web.archive.org/web/20240222121348/https://www.nature.com/articles/nature.2015.17756.pdf |archive-date=22 February 2024 |doi-access=free }}</ref><ref name="AP-20140614">{{Cite news |date=14 June 2015 |title=Comet lander Philae awakes from hibernation |url=https://www.latimes.com/science/sciencenow/la-comet-lander-philae-awakes-from-hibernation-20150614-story.html |url-status=live |archive-url=https://archive.today/20240222121711/https://www.latimes.com/science/sciencenow/la-comet-lander-philae-awakes-from-hibernation-20150614-story.html |archive-date=22 February 2024 |access-date=14 June 2015 |work=[[Los Angeles Times]] |agency=[[Associated Press]] }}</ref><ref name="esablog20150720">{{Cite web |last=Baldwin |first=Emily |date=20 July 2015 |title=Rosetta and Philae status update |url=http://blogs.esa.int/rosetta/2015/07/20/rosetta-and-philae-status-update/ |url-status=live |archive-url=https://archive.today/20150722132658/http://blogs.esa.int/rosetta/2015/07/20/rosetta-and-philae-status-update/ |archive-date=22 July 2015 |access-date=11 August 2015 |publisher=European Space Agency }}</ref> but contact was then lost. The lander's location was known to within a few tens of metres but it could not be seen. Its location was finally identified in photographs taken by ''Rosetta'' on 2 September 2016 as the orbiter was sent on orbits closer to the comet. The now-silent ''Philae'' was lying on its side in a deep crack in the shadow of a cliff. Knowledge of its location would help in interpretation of the images it had sent.<ref name="Philaefound" /><ref name="NYT-20160905">{{Cite news |last=Victor |first=Daniel |date=5 September 2016 |title=No Longer Missing: Rosetta's Philae Spacecraft Located on Comet |url=https://www.nytimes.com/2016/09/06/science/philae-spacecraft-rosetta-comet.html |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20231112094835/https://www.nytimes.com/2016/09/06/science/philae-spacecraft-rosetta-comet.html |archive-date=12 November 2023 |access-date=5 September 2016 |work=[[The New York Times]] }}</ref> On 30 September 2016, the ''Rosetta'' spacecraft ended its mission by crashing in the comet's Ma'at region.<ref name="space20160930">{{Cite news |last=Gannon |first=Megan |date=30 September 2016 |title=Goodbye, Rosetta! Spacecraft Crash-Lands on Comet in Epic Mission Finale |url=https://www.space.com/34254-rosetta-crash-lands-on-comet-mission-ends.html |url-status=live |archive-url=https://web.archive.org/web/20230609213804/https://www.space.com/34254-rosetta-crash-lands-on-comet-mission-ends.html |archive-date=9 June 2023 |access-date=1 October 2016 |work=[[Space.com]] }}</ref>

The lander is named after the [[Philae obelisk]], which bears a bilingual inscription and was used along with the [[Rosetta Stone]] to decipher [[Egyptian hieroglyphs]]. ''Philae'' was monitored and operated from [[German Aerospace Center|DLR]]'s Lander Control Center in [[Cologne]], Germany, supported by the [[CNES]]'s SONC in [[Toulouse]], France.<ref name="dlr-rosettacenter">{{Cite web |title=Rosetta Lander Control Center |url=http://www.dlr.de/rb/en/desktopdefault.aspx/tabid-4539/ |url-status=live |archive-url=https://web.archive.org/web/20231112100354/https://www.dlr.de/rb/en/desktopdefault.aspx/tabid-4539/ |archive-date=12 November 2023 |access-date=20 March 2015 |publisher=[[German Aerospace Center]] }}</ref>

== Mission ==
[[File:Landing on a Comet - The Rosetta Mission.webm|thumb|thumbtime=10|[[:File:Landing on a Comet - The Rosetta Mission.webm|Video report]] by the [[German Aerospace Center|German Aerospace Centre]] about ''Philae''{{'s}} landing mission. (10 min, English, in 1080p HD)]]
''Philae''{{'s}} mission was to land successfully on the surface of a comet, attach itself, and transmit data about the comet's composition. The ''Rosetta'' spacecraft and ''Philae'' lander were launched on an [[Ariane 5|Ariane 5G+]] rocket from [[French Guiana]] on 2 March 2004, 07:17 UTC, and travelled for 3,907 days (10.7 years) to Churyumov–Gerasimenko. Unlike the ''[[Deep Impact (spacecraft)|Deep Impact]]'' probe, which by design struck comet [[Tempel 1]]'s nucleus on 4 July 2005, ''Philae'' is not an impactor. Some of the instruments on the lander were used for the first time as autonomous systems during the Mars flyby on 25 February 2007. CIVA, one of the camera systems, returned some images while the ''Rosetta'' instruments were powered down, while ROMAP took measurements of the [[Magnetosphere of Mars|Martian magnetosphere]]. Most of the other instruments needed contact with the surface for analysis and stayed offline during the flyby.  An optimistic estimate of mission length following touchdown was "four to five months".<ref name="techrep20140814">{{Cite news |last=Gilpin |first=Lyndsey |date=14 August 2014 |title=The tech behind the Rosetta comet chaser: From 3D printing to solar power to complex mapping |url=http://www.techrepublic.com/article/the-tech-behind-the-rosetta-comet-chaser-from-3d-printing-to-solar-power-to-complex-mapping/ |url-status=dead |archive-url=https://web.archive.org/web/20140819184449/http://www.techrepublic.com/article/the-tech-behind-the-rosetta-comet-chaser-from-3d-printing-to-solar-power-to-complex-mapping/ |archive-date=19 August 2014 |work=[[TechRepublic]] }}</ref>

=== Scientific goals ===
The goals of the scientific mission have been summarised as follows: <blockquote>"The scientific goals of its experiments focus on [[Elemental analysis|elemental]], [[Isotope analysis|isotopic]], molecular and mineralogical composition of the cometary material, the characterization of physical properties of the surface and subsurface material, the large-scale structure and the magnetic and plasma environment of the nucleus. In particular, surface and sub-surface samples will be acquired and sequentially analyzed by a suite of instruments. Measurements will be performed primarily during descent and along the first five days following touch-down. "<ref name="Bibring2007">{{cite journal |title=The Rosetta Lander ("Philae") Investigations |journal=Space Science Reviews |first1=J.-P. |last1=Bibring |first2=H. |last2=Rosenbauer |first3=H. |last3=Boehnhardt |first4=S. |last4=Ulamec |first5=J. |last5=Biele |first6=S. |last6=Espinasse |first7=B. |last7=Feuerbacher |first8=P. |last8=Gaudon |first9=P. |last9=Hemmerich |first10=P. |last10=Kletzkine |first11=D. |last11=Moura |first12=R. |last12=Mugnuolo |first13=G. |last13=Nietner |first14=B. |last14=Pätz |first15=R. |last15=Roll |first16=H. |last16=Scheuerle |first17=K. |last17=Szegö |first18=K. |last18=Wittmann |display-authors=5 |volume=128 |issue=1–4 |pages=205–220 |date=February 2007 |doi=10.1007/s11214-006-9138-2 |bibcode=2007SSRv..128..205B|s2cid=51857150 }}</ref></blockquote>

== Landing and surface operations ==
[[File:Rosetta's Philae on Comet 67P Churyumov-Gerasimenko.jpg|thumb|Depiction of ''Philae'' on Churyumov-Gerasimenko]]
''Philae'' remained attached to the ''Rosetta'' spacecraft after rendezvousing with Churyumov–Gerasimenko on 6 August 2014. On 15 September 2014, ESA announced "{{Nowrap|Site J}}" on the smaller lobe of the comet as the lander's destination.<ref name="esa20140915">{{Cite press release |last=Bauer |first=Markus |date=15 September 2014 |title='J' Marks the Spot for Rosetta's Lander |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/J_marks_the_spot_for_Rosetta_s_lander |url-status=live |archive-url=https://web.archive.org/web/20230615202531/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/J_marks_the_spot_for_Rosetta_s_lander |archive-date=15 June 2023 |access-date=20 September 2014 |publisher=[[European Space Agency]] }}</ref> Following an ESA public contest in October 2014, {{Nowrap|Site J}} was renamed ''Agilkia'' in honour of [[Agilkia Island]].<ref name="space20141105">{{Cite news |last=Kramer |first=Miriam |date=5 November 2014 |title=Historic Comet Landing Site Has a New Name: Agilkia |url=https://www.space.com/27662-rosetta-comet-landing-site-agilkia.html |url-status=live |archive-url=https://web.archive.org/web/20230321104239/https://www.space.com/27662-rosetta-comet-landing-site-agilkia.html |archive-date=21 March 2023 |access-date=5 November 2014 |work=[[Space.com]] }}</ref>

A series of four [[Go/no go|go/no-go checks]] were performed on 11–12 November 2014. One of the final tests before detachment from ''Rosetta'' showed that the lander's [[cold-gas thruster]] was not working correctly, but the "go" was given anyway, as it could not be repaired.<ref name=CS1 /><ref name="esablog-20141112">{{Cite web |last=Baldwin |first=Emily |date=12 November 2014 |title=Rosetta and Philae Go for separation |url=https://blogs.esa.int/rosetta/2014/11/12/rosetta-and-philae-go-for-separation/ |url-status=live |archive-url=https://web.archive.org/web/20231112094844/https://blogs.esa.int/rosetta/2014/11/12/rosetta-and-philae-go-for-separation/ |archive-date=12 November 2023 |access-date=12 November 2014 |publisher=[[European Space Agency]] }}</ref> ''Philae'' detached from ''Rosetta'' on 12 November 2014 at 08:35 UTC [[Spacecraft Event Time|SCET]].<ref name="esa20140926">{{Cite press release |date=26 September 2014 |title=Rosetta to Deploy Lander on 12 November |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Rosetta_to_deploy_lander_on_12_November |url-status=live |archive-url=https://web.archive.org/web/20230501090227/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Rosetta_to_deploy_lander_on_12_November |archive-date=1 May 2023 |access-date=4 October 2014 |publisher=[[European Space Agency]] }}</ref><ref name="NASA-20141106-JP">{{Cite press release |last=Platt |first=Jane |date=6 November 2014 |title=Rosetta Races Toward Comet Touchdown |url=https://www.jpl.nasa.gov/news/rosetta-races-toward-comet-touchdown |url-status=live |archive-url=https://web.archive.org/web/20231112094851/https://www.jpl.nasa.gov/news/rosetta-races-toward-comet-touchdown |archive-date=12 November 2023 |access-date=7 November 2014 |publisher=[[NASA]] }}</ref>

=== Landing events ===
[[File:Signal received from Rosetta (12055070794).jpg|thumb|left|''[[Rosetta (spacecraft)|Rosetta]]'' signal received at [[European Space Operations Centre|ESOC]] in Darmstadt, Germany (20 January 2014)]]

''Philae''{{'s}} landing signal was received by Earth communication stations at 16:03&nbsp;UTC after a 28-minute delay.<ref name=nssdc /><ref name="bbc-20141112">{{Cite news |date=12 November 2014 |title=Probe makes historic comet landing |url=https://www.bbc.com/news/science-environment-30026398 |url-status=live |archive-url=https://web.archive.org/web/20240214121717/https://www.bbc.com/news/science-environment-30026398 |archive-date=14 February 2024 |access-date=12 November 2014 |work=[[BBC News]] }}</ref> Unknown to mission scientists at that time, the lander had bounced. It began performing scientific measurements while slowly moving away from the comet and coming back down, confusing the science team.<ref name="Lakdawalla2014-11-12">{{Cite web |last=Lakdawalla |first=Emily |author-link=Emily Lakdawalla |date=12 November 2014 |title=Philae Has Landed! [Updated] |url=https://www.planetary.org/articles/11120821-philae-has-landed |url-status=live |archive-url=https://web.archive.org/web/20231112094852/https://www.planetary.org/articles/11120821-philae-has-landed |archive-date=12 November 2023 |access-date=13 November 2014 |publisher=[[The Planetary Society]] }}</ref> Further analysis showed that it bounced twice.<ref name="NASA-20141113-DCA">{{Cite press release |last1=Agle |first1=D. C. |last2=Brown |first2=Dwayne |last3=Bauer |first3=Markus |date=13 November 2014 |title=Rosetta's Comet Lander Landed Three Times |url=https://www.jpl.nasa.gov/news/rosettas-comet-lander-landed-three-times |url-status=live |archive-url=https://web.archive.org/web/20231112155443/https://www.jpl.nasa.gov/news/rosettas-comet-lander-landed-three-times |archive-date=12 November 2023 |access-date=13 November 2014 |publisher=[[NASA]] }}</ref><ref name="esathree20141114" />

''Philae''{{'s}} first contact with the comet occurred at 15:34:04&nbsp;UTC SCET.<ref name="esagraze20141128">{{Cite web |last=Baldwin |first=Emily |date=28 November 2014 |title=Did Philae graze a crater rim during its first bounce? |url=https://blogs.esa.int/rosetta/2014/11/28/did-philae-graze-a-crater-rim-during-its-first-bounce/ |url-status=live |archive-url=https://web.archive.org/web/20230425215703/https://blogs.esa.int/rosetta/2014/11/28/did-philae-graze-a-crater-rim-during-its-first-bounce/ |archive-date=25 April 2023 |access-date=8 December 2014 |publisher=[[European Space Agency]] }}</ref> The probe rebounded off the comet's surface at {{convert|38|cm/s|abbr=on}} and rose to an altitude of approximately {{convert|1|km|mi|abbr=on|sigfig=1}}.<ref name="esathree20141114" /> For perspective, had the lander exceeded about {{convert|44|cm/s|abbr=on}}, it would have escaped the comet's gravity.<ref name="spaceluck20141114">{{Cite news |last=Wall |first=Mike |date=14 November 2014 |title=European Probe Survived Comet Landing with Luck and Great Design |url=https://www.space.com/27769-philae-comet-landing-survival-luck.html |url-status=live |archive-url=https://web.archive.org/web/20231201103153/https://www.space.com/27769-philae-comet-landing-survival-luck.html |archive-date=1 December 2023 |access-date=8 December 2014 |work=[[Space.com]] }}</ref> After detecting the touchdown, ''Philae''{{'s}} [[reaction wheel]] was automatically powered off, resulting in its momentum being transferred back into the lander. This caused the vehicle to begin rotating every 13 seconds.<ref name="esagraze20141128" /> During this first bounce, at 16:20&nbsp;UTC SCET, the lander is thought to have struck a surface [[prominence]], which slowed its rotation to once every 24 seconds and sent the craft tumbling.<ref name="esagraze20141128" /><ref name="unitoday20141202">{{Cite news |last=Howell |first=Elizabeth |date=2 December 2014 |title=Philae's Wild Comet Landing: Crater Grazing, Spinning And Landing In Parts Unknown |url=https://www.universetoday.com/116927/philaes-wild-comet-landing-crater-grazing-spinning-and-landing-in-parts-unknown/ |url-status=live |archive-url=https://web.archive.org/web/20231112155443/https://www.universetoday.com/116927/philaes-wild-comet-landing-crater-grazing-spinning-and-landing-in-parts-unknown/ |archive-date=12 November 2023 |access-date=8 December 2014 |work=Universe Today }}</ref> ''Philae'' touched down a second time at 17:25:26&nbsp;UTC SCET and rebounded at {{convert|3|cm/s|abbr=on}}.<ref name="esathree20141114" /><ref name="esagraze20141128" /> The lander came to a final stop on the surface at 17:31:17&nbsp;UTC SCET.<ref name="esagraze20141128" /> It sits in rough terrain, apparently in the shadow of a nearby cliff or crater wall, and is canted at an angle of around 30 degrees, but is otherwise undamaged.<ref name="skytel20141115">{{Cite magazine |last=Beatty |first=J. Kelly |date=15 November 2014 |title=Philae Wins Race to Return Comet Findings |url=http://www.skyandtelescope.com/astronomy-news/philae-lander-success-11152014/ |url-status=live |archive-url=https://web.archive.org/web/20240222151546/https://skyandtelescope.org/astronomy-news/philae-lander-success-11152014/ |archive-date=22 February 2024 |access-date=8 November 2014 |magazine=[[Sky & Telescope]] }}</ref> Its final location was determined initially by analysis of data from [[CONSERT]] in combination with the comet shape model based on images from the ''Rosetta'' orbiter,<ref name="esa-sitelocn">{{Cite web |last=Baldwin |first=Emily |date=21 November 2014 |title=Homing in on Philae's final landing site |url=https://blogs.esa.int/rosetta/2014/11/21/homing-in-on-philaes-final-landing-site/ |url-status=live |archive-url=https://web.archive.org/web/20240222151733/https://blogs.esa.int/rosetta/2014/11/21/homing-in-on-philaes-final-landing-site/ |archive-date=22 February 2024 |access-date=22 November 2014 |publisher=[[European Space Agency]] }}</ref> and later precisely by direct imaging from ''Rosetta''.<ref name="Philaefound" />

An analysis of telemetry indicated that the initial impact was softer than expected,<ref name="indep20141112">{{cite news |url=https://www.independent.co.uk/news/science/rosetta-space-mission-philae-probe-lands-safely-on-comet-67p-9857162.html |archive-url=https://ghostarchive.org/archive/20220526/https://www.independent.co.uk/news/science/rosetta-space-mission-philae-probe-lands-safely-on-comet-67p-9857162.html |archive-date=26 May 2022 |url-access=subscription |url-status=live |title=Rosetta space mission: Philae probe lands on Comet 67P |work=The Independent |first=Steve |last=Connor |date=12 November 2014 |access-date=11 August 2015}}</ref> that the harpoons had not deployed, and that the thruster had not fired.<ref name="cnnprob20141112">{{Cite news |last=Gilbert |first=Dave |date=12 November 2014 |title=Philae touches down on the surface of a comet |url=https://edition.cnn.com/2014/11/12/world/comet-landing-countdown |url-status=live |archive-url=https://web.archive.org/web/20231224043203/https://edition.cnn.com/2014/11/12/world/comet-landing-countdown/ |archive-date=24 December 2023 |access-date=12 November 2014 |work=[[CNN]] }}</ref><ref name="newsciprob20141113">{{Cite magazine |last=Aron |first=Jacob |date=13 November 2014 |title=Problems hit Philae after historic first comet landing |url=https://www.newscientist.com/article/dn26547-problems-hit-philae-after-historic-first-comet-landing/ |url-status=live |archive-url=https://web.archive.org/web/20230930102707/https://www.newscientist.com/article/dn26547-problems-hit-philae-after-historic-first-comet-landing/ |archive-date=30 September 2023 |access-date=13 November 2014 |magazine=[[New Scientist]] }}</ref> The harpoon propulsion system contained 0.3 grams of [[nitrocellulose]], which was shown by [[Copenhagen Suborbitals]] in 2013 to be unreliable in a vacuum.<ref name="ingenioren20141113">{{Cite news |last=Djursing |first=Thomas |date=13 November 2014 |title=ESA skrev til danske raketbyggere om eksplosiv-problem på Philae |trans-title=ESA wrote to Danish rocket builders about explosive problem on Philae |url=https://ing.dk/artikel/esa-skrev-til-danske-raketbyggere-om-eksplosiv-problem-paa-philae |url-status=live |archive-url=https://web.archive.org/web/20230426233818/https://ing.dk/artikel/esa-skrev-til-danske-raketbyggere-om-eksplosiv-problem-paa-philae |archive-date=26 April 2023 |access-date=13 November 2014 |work=[[Ingeniøren]] |language=da }}</ref>

=== Operations and communication loss ===
[[File:ESA Rosetta NAVCAM Agilkia landing site on comet 67P 20141106 mosaic.jpg|thumb|300px|''Philae''{{'s}} intended landing site Agilkia (Site J)]]

The primary battery was designed to power the instruments for about 60 hours.<ref name="PhilaeBBC1" /> ESA expected that a secondary rechargeable battery would be partially filled by the solar panels attached to the outside of the lander, but the limited sunlight (90 minutes per 12.4-hour comet day<ref name="Harwood2014.11.15" />) at the actual landing site was inadequate to maintain ''Philae''{{'s}} activities, at least in this phase of the comet's orbit.<ref name="Lakdawalla2014-11-13">{{Cite web |last=Lakdawalla |first=Emily |author-link=Emily Lakdawalla |date=13 November 2014 |title=Philae status, a day later |url=https://www.planetary.org/articles/11131025-philae-status-a-day-later |url-status=live |archive-url=https://web.archive.org/web/20231112094838/https://www.planetary.org/articles/11131025-philae-status-a-day-later |archive-date=12 November 2023 |access-date=14 November 2014 |publisher=[[The Planetary Society]] }}</ref><ref name="Djursing2014-11-13">{{Cite news |last=Djursing |first=Thomas |date=13 November 2014 |title=Kometsonden Philae står skævt under en klippe og får for lidt sollys |trans-title=The comet probe Philae is tilted under a rock and receives too little sunlight |url=https://ing.dk/artikel/kometsonden-philae-staar-skaevt-under-en-klippe-og-faar-lidt-sollys |url-status=live |archive-url=https://web.archive.org/web/20231112100339/https://ing.dk/artikel/kometsonden-philae-staar-skaevt-under-en-klippe-og-faar-lidt-sollys |archive-date=12 November 2023 |access-date=14 November 2014 |work=[[Ingeniøren]] |language=da }}</ref>

On the morning of 14 November 2014, the battery charge was estimated to be only enough for continuing operations for the remainder of the day. After first obtaining data from instruments whose operation did not require mechanical movement, comprising about 80% of the planned initial science observations, both the MUPUS soil penetrator and the SD2 drill were commanded to deploy. Subsequently, MUPUS data<ref name="Lakdawalla2014-11-14">{{Cite web |last=Lakdawalla |first=Emily |author-link=Emily Lakdawalla |date=14 November 2014 |title=Philae update: My last day in Darmstadt, possibly Philae's last day of operations |url=https://www.planetary.org/articles/11141330-philae-update-my-last-day-in-darmstadt |url-status=live |archive-url=https://web.archive.org/web/20231112094953/https://www.planetary.org/articles/11141330-philae-update-my-last-day-in-darmstadt |archive-date=12 November 2023 |access-date=14 November 2014 |publisher=[[The Planetary Society]] }}</ref> as well as COSAC and Ptolemy data were returned. A final set of CONSERT data was also downlinked towards the end of operations. During the evening's transmission session, ''Philae'' was raised by {{convert|4|cm}} and its body rotated 35 degrees to more favourably position the largest solar panel to capture the most sunlight in the future.<ref name="bbcnews20141115">{{Cite news |last=Amos |first=Jonathan |date=15 November 2014 |title=Philae comet lander sends more data before losing power |url=https://www.bbc.com/news/science-environment-30058176 |url-status=live |archive-url=https://web.archive.org/web/20231120181130/https://www.bbc.com/news/science-environment-30058176 |archive-date=20 November 2023 |access-date=8 December 2014 |work=[[BBC News]] }}</ref><ref name="Lakdawalla2014-11-15">{{Cite web |last=Lakdawalla |first=Emily |author-link=Emily Lakdawalla |date=15 November 2014 |title=Now Philae down to sleep |url=https://www.planetary.org/articles/20141115-now-philae-down-to-sleep |url-status=live |archive-url=https://web.archive.org/web/20231203213414/https://www.planetary.org/articles/20141115-now-philae-down-to-sleep |archive-date=3 December 2023 |access-date=17 November 2014 |publisher=[[The Planetary Society]] }}</ref> Shortly afterwards, electrical power dwindled rapidly and all instruments were forced to shut down. The downlink rate slowed to a trickle before coming to a stop.<ref name="Harwood2014.11.15">{{Cite news |last=Harwood |first=William |date=15 November 2014 |title=Loss of contact with Philae |url=https://spaceflightnow.com/2014/11/15/loss-of-contact-with-philae/ |url-status=live |archive-url=https://web.archive.org/web/20230604032407/https://spaceflightnow.com/2014/11/15/loss-of-contact-with-philae/ |archive-date=4 June 2023 |access-date=15 November 2014 |work=Spaceflight Now }}</ref> Contact was lost on 15 November at 00:36&nbsp;UTC.<ref name="esa-asleep">{{Cite web |last=Scuka |first=Daniel |date=15 November 2014 |title=Our Lander's Asleep |url=https://blogs.esa.int/rosetta/2014/11/15/our-landers-asleep/ |url-status=live |archive-url=https://web.archive.org/web/20231222112906/https://blogs.esa.int/rosetta/2014/11/15/our-landers-asleep/ |archive-date=22 December 2023 |access-date=15 November 2014 |publisher=[[European Space Agency]] }}</ref>

The [[German Aerospace Center]]'s lander manager [[Stephan Ulamec]] stated:
{{quote|Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence&nbsp;... This machine performed magnificently under tough conditions, and we can be fully proud of the incredible scientific success Philae has delivered.<ref name="esa-asleep" />}}

=== Instrument results ===
Data from the SESAME instrument determined that, rather than being "soft and fluffy" as expected, ''Philae''{{'s}} first touchdown site held a large amount of water ice under a layer of granular material about {{convert|25|cm|abbr=on}} deep.<ref name="space20150730">{{Cite news |last=Wall |first=Mike |date=30 July 2015 |title=Surprising Comet Discoveries by Rosetta's Philae Lander Unveiled |url=http://www.space.com/30100-comet-landing-discoveries-rosetta-philae-lander.html |url-status=live |archive-url=https://web.archive.org/web/20231112100337/https://www.space.com/30100-comet-landing-discoveries-rosetta-philae-lander.html |archive-date=12 November 2023 |access-date=31 July 2015 |work=[[Space.com]] }}</ref> It found that the mechanical strength of the ice was high and that cometary activity in that region was low. At the final landing site, the MUPUS instrument was unable to hammer very far into the comet's surface, despite power being gradually increased. This area was determined to have the consistency of solid ice<ref name="DLR_2014.11.17">{{Cite web |date=17 November 2014 |title=Churyumov-Gerasimenko – hard ice and organic molecules |url=https://www.dlr.de/en/latest/news/2014/20141117_churyumov-gerasimenko-hard-ice-and-organic-molecules_12176/@@download/file |url-status=live |archive-url=https://web.archive.org/web/20240222153056/https://www.dlr.de/en/latest/news/2014/20141117_churyumov-gerasimenko-hard-ice-and-organic-molecules_12176/@@download/file |archive-date=22 February 2024 |access-date=18 November 2014 |publisher=[[German Aerospace Center]] |type=PDF }}</ref><ref name="timesindia20141118">{{Cite news |last=Sinha |first=Kounteya |date=18 November 2014 |title=Philae reveals presence of large amount of water ice on the comet |url=https://timesofindia.indiatimes.com/home/science/Philae-reveals-presence-of-large-amount-of-water-ice-on-the-comet/articleshow/45195549.cms |url-status=live |archive-url=https://web.archive.org/web/20231112100339/https://timesofindia.indiatimes.com/home/science/philae-reveals-presence-of-large-amount-of-water-ice-on-the-comet/articleshow/45195549.cms |archive-date=12 November 2023 |access-date=18 November 2014 |work=[[The Times of India]] |agency=Times News Network }}</ref> or [[pumice]].<ref name="eos20150731">{{Cite magazine |last=Wendel |first=JoAnna |date=31 July 2015 |title=Comet Lander Makes a Hard Discovery |url=https://eos.org/articles/comet-lander-makes-a-hard-discovery |url-status=live |archive-url=https://web.archive.org/web/20231027115440/https://eos.org/articles/comet-lander-makes-a-hard-discovery |archive-date=27 October 2023 |magazine=[[Eos (magazine)|Eos]] |publisher=[[American Geophysical Union]] |volume=96 |doi=10.1029/2015EO033623 |doi-access=free }}</ref>

In the atmosphere of the comet, the COSAC instrument detected the presence of molecules containing carbon and hydrogen. Soil elements could not be assessed, because the lander was unable to drill into the comet surface, likely due to hard ice.<ref name="guardian20141119">{{Cite news |last=Gray |first=Richard |date=19 November 2014 |title=Rosetta mission lander detects organic molecules on surface of comet |url=https://www.theguardian.com/science/2014/nov/18/philae-lander-comet-surface-detects-organic-molecules |url-status=live |archive-url=https://web.archive.org/web/20231112094834/https://www.theguardian.com/science/2014/nov/18/philae-lander-comet-surface-detects-organic-molecules |archive-date=12 November 2023 |access-date=18 December 2014 |work=[[The Guardian]] }}</ref> The SD2 drill went through the necessary steps to deliver a surface sample to the COSAC instrument,<ref name="DLR_2014.11.17" /> but nothing entered the COSAC ovens.<ref name="hand-20141117">{{Cite tweet |first=Eric |last=Hand |number=534413817040867328 |user=erichand |title=COSAC PI: Drill tried to deliver sample. Ovens heated up. But data show no actual delivery. "There's nothing in it." #CometLanding |date=17 November 2014 |access-date=8 December 2014 |archive-url=https://web.archive.org/web/20150612090813/https://twitter.com/erichand/status/534413817040867328 |archive-date=12 June 2015 |url-status=live }}</ref>

Upon ''Philae''{{'s}} first touchdown on the comet's surface, COSAC measured material at the bottom of the vehicle, which was disturbed by the landing, while the Ptolemy instrument measured material at the top of the vehicle. Sixteen [[organic compound]]s were detected, four of which were seen for the first time on a comet, including [[acetamide]], [[acetone]], [[methyl isocyanate]] and [[propionaldehyde]].<ref name="ap-20150730">{{Cite news |last=Jordans |first=Frank |date=30 July 2015 |title=Philae probe finds evidence that comets can be cosmic labs |url=https://apnews.com/general-news-international-news-a8c32853d364494ca482c8e3dc00ced0 |url-status=live |archive-url=https://web.archive.org/web/20240222154017/https://apnews.com/general-news-international-news-a8c32853d364494ca482c8e3dc00ced0 |archive-date=22 February 2024 |access-date=30 July 2015 |work=[[Associated Press]] }}</ref><ref name="esa20150730">{{Cite press release |editor-last=Altobelli |editor-first=Nicolas |editor2-last=Bibring |editor2-first=Jean-Pierre |editor3-last=Ulamec |editor3-first=Stephan |date=30 July 2015 |title=Science on the Surface of a Comet |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Science_on_the_surface_of_a_comet |url-status=live |archive-url=https://web.archive.org/web/20240112110949/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Science_on_the_surface_of_a_comet |archive-date=12 January 2024 |access-date=30 July 2015 |publisher=[[European Space Agency]] }}</ref><ref name="SCI-20150731">{{Cite journal |last1=Bibring |first1=J.-P. |last2=Taylor |first2=M. G. G. T. |last3=Alexander |first3=C. |last4=Auster |first4=U. |last5=Biele |first5=J. |last6=Finzi |first6=A. Ercoli |last7=Goesmann |first7=F. |last8=Klingehoefer |first8=G. |last9=Kofman |first9=W. |last10=Mottola |first10=S. |last11=Seidenstiker |first11=K. J. |last12=Spohn |first12=T. |last13=Wright |first13=I. |display-authors=5 |date=31 July 2015 |title=Philae's First Days on the Comet |url=https://elib.dlr.de/97953/1/Science-2015-Bibring-493.pdf |url-status=live |journal=[[Science (journal)|Science]] |volume=349 |issue=6247 |page=493 |bibcode=2015Sci...349..493B |doi=10.1126/science.aac5116 |pmid=26228139 |archive-url=https://web.archive.org/web/20240113173750/https://elib.dlr.de/97953/1/Science-2015-Bibring-493.pdf |archive-date=13 January 2024 |doi-access=free }}</ref>

=== Reawakening and subsequent loss of communication ===
[[File:67P Churyumov-Gerasimenko - Rosetta (32755885495).png|thumb|right|[[67P/Churyumov–Gerasimenko|Comet Churyumov–Gerasimenko]] in March 2015 as imaged by ''Rosetta'' in true colour]]
On 13 June 2015 at 20:28&nbsp;UTC, ground controllers received an 85-second transmission from ''Philae'', forwarded by ''Rosetta'', indicating that the lander was in good health and had sufficiently recharged its batteries to come out of [[Safe mode (spacecraft)|safe mode]].<ref name="NAT-20150614" /><ref name="esaphilae20150614">{{Cite web |last=Baldwin |first=Emily |date=14 June 2015 |title=Rosetta's lander Philae wakes up from hibernation |url=https://blogs.esa.int/rosetta/2015/06/14/rosettas-lander-philae-wakes-up-from-hibernation/ |url-status=live |archive-url=https://web.archive.org/web/20240209213105/https://blogs.esa.int/rosetta/2015/06/14/rosettas-lander-philae-wakes-up-from-hibernation/ |archive-date=9 February 2024 |access-date=14 June 2015 |publisher=[[European Space Agency]] }}</ref> ''Philae'' sent historical data indicating that although it had been operating earlier than 13 June 2015, it had been unable to contact ''Rosetta'' before that date.<ref name="NAT-20150614" /> The lander reported that it was operating with 24 watts of electrical power at {{convert|-35|C|F|abbr=on}}.<ref name="esaphilae20150614" />

A new contact between ''Rosetta'' and ''Philae'' was confirmed on 19 June 2015.<ref name="esaphilae20150619">{{Cite web |last=Mignone |first=Claudia |date=19 June 2015 |title=Rosetta and Philae in contact again |url=https://blogs.esa.int/rosetta/2015/06/19/rosetta-and-philae-in-contact-again/ |url-status=live |archive-url=https://web.archive.org/web/20231112094847/https://blogs.esa.int/rosetta/2015/06/19/rosetta-and-philae-in-contact-again/ |archive-date=12 November 2023 |access-date=20 June 2015 |publisher=[[European Space Agency]] }}</ref> The first signal was received on the ground from ''Rosetta'' at 13:37&nbsp;UTC, while a second signal was received at 13:54&nbsp;UTC. These contacts lasted about two minutes each and delivered additional status data.<ref name="esaphilae20150619" /> By 26 June 2015, there had been a total of seven intermittent contacts between the lander and orbiter.<ref name="transient contacts">{{Cite news |last=Baldwin |first=Emily |date=26 June 2015 |title=Rosetta and Philae: Searching for a good signal |url=https://blogs.esa.int/rosetta/2015/06/26/rosetta-and-philae-searching-for-a-good-signal/ |url-status=live |archive-url=https://web.archive.org/web/20231120220619/https://blogs.esa.int/rosetta/2015/06/26/rosetta-and-philae-searching-for-a-good-signal/ |archive-date=20 November 2023 |access-date=26 June 2015 |publisher=[[European Space Agency]] }}</ref> There were two opportunities for contact between the two spacecraft each Earth day, but their duration and quality depended on the orientation of the transmitting antenna on ''Philae'' and the location of ''Rosetta'' along its trajectory around the comet. Similarly, as the comet rotated, ''Philae'' was not always in sunlight and thus not always generating enough power via its solar panels to receive and transmit signals. ESA controllers continued to try to establish a stable contact duration of at least 50 minutes.<ref name="transient contacts" />

Had ''Philae'' landed at the planned site of Agilkia in November 2014, its mission would probably have ended in March 2015 due to the higher temperatures of that location as solar heating increased.<ref name="planning2015">{{Cite press release |date=15 June 2015 |title=Philae wake-up triggers intense planning |url=https://www.esa.int/Enabling_Support/Operations/Philae_wake-up_triggers_intense_planning |url-status=live |archive-url=https://web.archive.org/web/20240112110956/https://www.esa.int/Enabling_Support/Operations/Philae_wake-up_triggers_intense_planning |archive-date=12 January 2024 |access-date=16 June 2015 |publisher=[[European Space Agency]] }}</ref> {{As of|2015|06}}, ''Philae''{{'s}} key remaining experiment was to drill into the comet's surface to determine its chemical composition.<ref name="bbc-20150619">{{Cite news |last=Amos |first=Jonathan |date=19 June 2015 |title=Comet lander Philae renews contact |url=https://www.bbc.com/news/science-environment-33206661 |url-status=live |archive-url=https://web.archive.org/web/20231112094915/https://www.bbc.com/news/science-environment-33206661 |archive-date=12 November 2023 |access-date=19 June 2015 |work=[[BBC News]] }}</ref> Ground controllers sent commands to power up the [[CONSERT]] radar instrument on 5 July 2015, but received no immediate response from the lander. Confirmation was eventually received on 9 July, when the lander transmitted measurement data from the instrument.<ref name="DLR-20150710">{{Cite press release |date=10 July 2015 |title=New communication with Philae – commands executed successfully |url=https://www.dlr.de/en/latest/news/2015/20150710_new-communication-with-philae-commands-executed-successfully_14156 |url-status=live |archive-url=https://web.archive.org/web/20240222155032/https://www.dlr.de/en/latest/news/2015/20150710_new-communication-with-philae-commands-executed-successfully_14156 |archive-date=22 February 2024 |access-date=11 July 2015 |publisher=[[German Aerospace Center]] }}</ref>

Immediately after its reawakening, housekeeping data suggested that the lander's systems were healthy, and mission control uploaded commands for ''Rosetta'' to establish a new orbit and [[nadir]] so as to optimize communications, diagnostics, and enable new science investigations with ''Philae''.<ref name="planning2015" /><ref name="AP-20150615">{{Cite news |last=Moulson |first=Geir |date=15 June 2015 |title=Europe's comet lander makes 2nd contact after waking up |url=https://www.miamiherald.com/news/nation-world/world/article24398281.html |url-status=live |archive-url=https://web.archive.org/web/20240222155546/https://www.miamiherald.com/news/nation-world/world/article24398281.html |archive-date=22 February 2024 |access-date=16 June 2015 |work=[[Miami Herald]] |agency=[[Associated Press]] }}</ref><ref name="bbc-20150617">{{Cite news |last=Amos |first=Jonathan |date=17 June 2015 |title=Controllers wait on Philae link |url=https://www.bbc.com/news/science-environment-33163835 |url-status=live |archive-url=https://web.archive.org/web/20231112094838/https://www.bbc.com/news/science-environment-33163835 |archive-date=12 November 2023 |access-date=17 June 2015 |work=[[BBC News]] }}</ref> However, controllers had difficulties establishing a stable communications connection with the lander. The situation was not helped by the need to keep ''Rosetta'' at a greater and safer distance from the comet as it became more active.<ref name="earthsky-20150629">{{Cite news |date=29 June 2015 |title=Rosetta team struggles with Philae link |url=https://earthsky.org/space/rosetta-struggles-with-stable-philae-link/ |url-status=live |archive-url=https://web.archive.org/web/20231112094953/https://earthsky.org/space/rosetta-struggles-with-stable-philae-link/ |archive-date=12 November 2023 |access-date=30 June 2015 |work=Earthsky }}</ref>  The last communication was on 9 July 2015,<ref name="esablog20150720" /> and mission controllers were unable to instruct ''Philae'' to carry out new investigations.<ref name="sen20150814">{{Cite news |last=Sutherland |first=Paul |date=14 August 2015 |title=Comet's fizzing all over during closest approach to the Sun |url=http://sen.com/news/comet-s-fizzing-all-over-during-closest-approach-to-the-sun |url-status=dead |archive-url=https://web.archive.org/web/20150822152511/http://sen.com/news/comet-s-fizzing-all-over-during-closest-approach-to-the-sun |archive-date=22 August 2015 |work=Space Exploration Network }}</ref><ref name="sen20150720">{{Cite news |last=Sutherland |first=Paul |date=20 July 2015 |title=Rosetta sends software patch to fix Philae |url=http://sen.com/news/rosetta-sends-software-patch-to-fix-philae |url-status=dead |archive-url=https://web.archive.org/web/20150822085720/http://sen.com/news/rosetta-sends-software-patch-to-fix-philae |archive-date=22 August 2015 |access-date=17 August 2015 |work=Space Exploration Network }}</ref> Subsequently, ''Philae'' failed to respond to further commands, and by January 2016, controllers acknowledged no further communications were likely.<ref name="newsci20160111">{{Cite magazine |last=Aron |first=Jacob |date=11 January 2016 |title=Philae lander fails to respond to last-ditch efforts to wake it |url=https://www.newscientist.com/article/dn28752-philae-lander-fails-to-respond-to-last-ditch-efforts-to-wake-it/ |url-status=live |archive-url=https://web.archive.org/web/20231112094853/https://www.newscientist.com/article/dn28752-philae-lander-fails-to-respond-to-last-ditch-efforts-to-wake-it/ |archive-date=12 November 2023 |access-date=12 January 2016 |magazine=[[New Scientist]] }}</ref>

On 27 July 2016, at 09:00&nbsp;[[UTC]], ESA switched off the Electrical Support System Processor Unit (ESS) onboard ''Rosetta'', making further communications with ''Philae'' impossible.<ref name="farewellphilae">{{Cite web |last=Mignone |first=Claudia |date=26 July 2016 |title=Farewell, silent Philae |url=https://blogs.esa.int/rosetta/2016/07/26/farewell-silent-philae/ |url-status=live |archive-url=https://web.archive.org/web/20161227033026/https://blogs.esa.int/rosetta/2016/07/26/farewell-silent-philae/ |archive-date=27 December 2016 |access-date=29 July 2016 |publisher=[[European Space Agency]] }}</ref><ref name="nature-20160726">{{Cite news |last=Gibney |first=Elizabeth |date=26 July 2016 |title=Philae comet lander goes quiet for good |url=https://www.nature.com/articles/nature.2016.20338.pdf |url-status=live |archive-url=https://web.archive.org/web/20221020185024/https://www.nature.com/articles/nature.2016.20338.pdf |archive-date=20 October 2022 |access-date=27 August 2016 |doi=10.1038/nature.2016.20338 |issn=1476-4687 |doi-access=free |journal=[[Nature (journal)|Nature]] }}</ref>

===Location===
The lander was located on 2 September 2016 by the narrow-angle camera aboard ''Rosetta'' as it was slowly making its descent to the comet.<ref name="Philaefound" /> The search for the lander had been on-going during the ''Rosetta'' mission, using telemetry data and comparison of pictures taken before and after the lander's touchdown, looking for signs of the lander's specific reflectivity.<ref name="esablog-20150611">{{Cite web |last=Baldwin |first=Emily |date=11 June 2015 |title=The quest to find Philae |url=https://blogs.esa.int/rosetta/2015/06/11/the-quest-to-find-philae-2/ |url-status=live |archive-url=https://web.archive.org/web/20240212031440/https://blogs.esa.int/rosetta/2015/06/11/the-quest-to-find-philae-2/ |archive-date=12 February 2024 |access-date=5 September 2016 |publisher=[[European Space Agency]] }}</ref>

The search area was narrowed down to the most promising candidate, which was confirmed by a picture taken at a distance of {{convert|2.7|km|mi|abbr=on}}, clearly showing the lander. The lander sits on its side wedged into a dark crevice of the comet, explaining the lack of electrical power and proper communication with the probe.<ref name="Philaefound" /> Knowing its exact location provides information needed to put ''Philae''{{'s}} two days of science into proper context.<ref name="Philaefound" />

== Design ==
[[File:Rosetta and Philae (crop).jpg|thumb|left|''Rosetta'' and ''Philae'']]
The lander was designed to deploy from the main spacecraft body and descend from an orbit of {{convert|22.5|km|0}} along a [[Projectile motion|ballistic trajectory]].<ref name="bbcnews20140926">{{Cite news |last=Amos |first=Jonathan |date=26 September 2014 |title=Rosetta: Date fixed for historic comet landing attempt |url=https://www.bbc.com/news/science-environment-29380448 |url-status=live |archive-url=https://web.archive.org/web/20240120061628/https://www.bbc.com/news/science-environment-29380448 |archive-date=20 January 2024 |access-date=29 September 2014 |work=[[BBC News]] }}</ref> It would touch down on the comet's surface at a velocity of around {{convert|1|m/s|km/h mph}}.<ref name="bbcnews20140825">{{Cite news |last=Amos |first=Jonathan |date=25 August 2014 |title=Rosetta mission: Potential comet landing sites chosen |url=https://www.bbc.com/news/science-environment-28923010 |url-status=live |archive-url=https://web.archive.org/web/20231112094850/https://www.bbc.com/news/science-environment-28923010 |archive-date=12 November 2023 |access-date=25 August 2014 |work=[[BBC News]] }}</ref> The legs were designed to dampen the initial impact to avoid bouncing as the comet's escape velocity is only around {{convert|1|m/s|km/h mph|abbr=on}},<ref name="mpg20140120">{{Cite press release |last=Dambeck |first=Thorsten |date=20 January 2014 |title=Expedition to primeval matter |url=https://www.mpg.de/7769243/expedition-primeval_matter |url-status=live |archive-url=https://web.archive.org/web/20230604040223/https://www.mpg.de/7769243/expedition-primeval_matter |archive-date=4 June 2023 |access-date=19 September 2014 |publisher=[[Max Planck Society]] }}</ref> and the impact energy was intended to drive ice screws into the surface.<ref name="mpgblog-20141110">{{Cite web |last=Böhnhardt |first=Hermann |date=10 November 2014 |title=About the Upcoming Philae Separation, Descent and Landing |url=https://www.mps.mpg.de/en/rosetta/philae-blog |url-status=live |archive-url=https://web.archive.org/web/20231206104512/https://www.mps.mpg.de/en/rosetta/philae-blog |archive-date=6 December 2023 |access-date=11 November 2014 |publisher=[[Max Planck Institute for Solar System Research]] }}</ref> ''Philae'' was to then fire a [[harpoon]] into the surface at {{convert|70|m/s|km/h mph|abbr=on}} to anchor itself.<ref name="Biele2009">{{cite book |chapter-url=https://books.google.com/books?id=5YIPCbnTCeMC&pg=PA297 |chapter=The Strength of Cometary Surface Material: Relevance of Deep Impact Results for Philae Landing on a Comet |title=Deep Impact as a World Observatory Event: Synergies in Space, Time, and Wavelength |publisher=Springer |series=ESO Astrophysics Symposia |first1=J. |last1=Biele |first2=S. |last2=Ulamec |first3=L. |last3=Richter |first4=E. |last4=Kührt |first5=J. |last5=Knollenberg |first6=D. |last6=Möhlmann |editor1-first=Hans Ulrich |editor1-last=Käufl |editor2-first=Christiaan |editor2-last=Sterken |page=297 |year=2009 |isbn=978-3-540-76958-3 |bibcode=2009diwo.conf..285B |doi=10.1007/978-3-540-76959-0_38}}</ref><ref name="Biele2013">{{Cite conference |last1=Biele |first1=Jens |last2=Ulamec |first2=Stephan |date=March 2013 |title=Preparing for Landing on a Comet – The Rosetta Lander Philae |url=https://www.lpi.usra.edu/meetings/lpsc2013/pdf/1392.pdf |conference=44th Lunar and Planetary Science Conference |location=The Woodlands, Texas |publisher=[[Lunar and Planetary Institute]] |bibcode=2013LPI....44.1392B |id=LPI Contribution No. 1719 |archive-url=https://web.archive.org/web/20231209023314/https://www.lpi.usra.edu/meetings/lpsc2013/pdf/1392.pdf |archive-date=9 December 2023 |conference-url=https://www.lpi.usra.edu/meetings/lpsc2013/ |url-status=live }}</ref> A thruster on top of ''Philae'' was to have fired to lessen the bounce upon impact and to reduce the recoil from harpoon firing.<ref name="CS1">{{Cite news |last=Spotts |first=Pete |date=12 November 2014 |title=Will Philae successfully land on comet? Thruster trouble heightens drama |url=https://www.csmonitor.com/Science/2014/1112/Will-Philae-successfully-land-on-comet-Thruster-trouble-heightens-drama |url-status=live |archive-url=https://web.archive.org/web/20231112094835/https://www.csmonitor.com/Science/2014/1112/Will-Philae-successfully-land-on-comet-Thruster-trouble-heightens-drama |archive-date=12 November 2023 |work=[[The Christian Science Monitor]] }}</ref> During the landing, the harpoons did not fire and the thruster failed to operate, leading to a multiple-contact landing.<ref name="cnnprob20141112" /><ref name="newsciprob20141113" />

Communications with Earth used the ''Rosetta'' orbiter as a [[Broadcast relay station|relay station]] to reduce the electrical power needed. The mission duration on the surface was planned to be at least one week, but an extended mission lasting months was considered possible.{{citation needed|date=November 2020}}

The main structure of the lander is made from [[Carbon-fiber-reinforced polymer|carbon fiber]], shaped into a plate maintaining mechanical stability, a platform for the science instruments, and a [[hexagon]]al "sandwich" to connect all the parts. The total mass is about {{convert|100|kg|lb}}. Its exterior is covered with [[solar cell]]s for power generation.<ref name="Biele2002" />

The ''Rosetta'' mission was originally planned to rendezvous with the comet [[46P/Wirtanen]]. A failure in a previous [[Ariane 5]] launch vehicle closed the [[launch window]] to reach the comet with the same rocket.<ref name="esa-faq">{{Cite web |title=Why was 67P/Churyumov-Gerasimenko selected as the target comet instead of Wirtanen? |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Frequently_asked_questions |url-status=live |archive-url=https://web.archive.org/web/20240217150512/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Frequently_asked_questions |archive-date=17 February 2024 |access-date=24 November 2014 |website=Rosetta's Frequently Asked Questions |publisher=[[European Space Agency]] |quote=The other options, including a launch to Wirtanen in 2004, would have required a more powerful launch vehicle, either an [[Ariane 5 ECA]] or a [[Proton (rocket family)|Proton]]. }}</ref> It resulted in a change in target to the comet [[67P/Churyumov–Gerasimenko]].<ref name=esa-faq /> The larger mass of Churyumov–Gerasimenko and the resulting increased impact velocity required that the landing gear of the lander be strengthened.<ref name="esasci20141114">{{Cite web |date=14 November 2014 |title=Highlights from the Rosetta mission thus far |url=https://sci.esa.int/web/rosetta/-/54456-highlights-from-the-rosetta-mission-thus-far |url-status=live |archive-url=https://web.archive.org/web/20231222185945/https://sci.esa.int/web/rosetta/-/54456-highlights-from-the-rosetta-mission-thus-far |archive-date=22 December 2023 |access-date=6 July 2015 |publisher=[[European Space Agency]] }}</ref>

{| class="wikitable" style="margin: 1em auto;"
|-
! Spacecraft component
! colspan=2 | Mass<ref name="Bibring2007" />{{rp|208}}
|-
| Structure || {{convert|18.0|kg|lb|abbr=on|disp=table}}
|-
| [[Spacecraft thermal control|Thermal control system]] || {{convert|3.9|kg|lb|abbr=on|disp=table}}
|-
| Power system || {{convert|12.2|kg|lb|abbr=on|disp=table}}
|-
| Active descent system  || {{convert|4.1|kg|lb|abbr=on|disp=table}}
|-
| [[Reaction wheel]] || {{convert|2.9|kg|lb|abbr=on|disp=table}}
|-
| Landing gear || {{convert|10.0|kg|lb|0|abbr=on|disp=table}}
|-
| Anchoring system || {{convert|1.4|kg|lb|abbr=on|disp=table}}
|-
| Central data management system || {{convert|2.9|kg|lb|abbr=on|disp=table}}
|-
| Telecommunications system || {{convert|2.4|kg|lb|abbr=on|disp=table}}
|-
| Common electronics box || {{convert|9.8|kg|lb|abbr=on|disp=table}}
|-
| Mechanical support system, harness, balancing mass || {{convert|3.6|kg|lb|abbr=on|disp=table}}
|-
| [[#Instruments|Scientific payload]] || {{convert|26.7|kg|lb|abbr=on|disp=table}}
|- style="background-color: #f2f2f2; font-weight: bold;"
!  Sum !! {{convert|97.9|kg|lb|abbr=on|disp=table}}
|}

=== Power management ===
''Philae''{{'s}} power management was planned for two phases. In the first phase, the lander operated solely on battery power. In the second phase, it was to run on backup batteries recharged by solar cells.<ref name="techrep20140814" />

The power subsystem comprises two batteries: a non-rechargeable primary 1000 watt-hour battery to provide power for the first 60 hours and a secondary 140 watt-hour battery recharged by the solar panels to be used after the primary is exhausted. The solar panels cover {{convert|2.2|m2|sqft}} and were designed to deliver up to 32 watts at a distance of 3&nbsp;AU from the Sun.<ref name="dlrPdf" />

=== Instruments ===
[[File:Atterrisseur-Philae-15494442575 099c1ff083 o.png|thumb|250px|''Philae''{{'s}} instruments]]

The science payload of the lander consists of ten instruments totalling {{convert|26.7|kg|lb}}, making up just over one quarter of the mass of the lander.<ref name="Bibring2007" />

; [[APXS]]
:The ''Alpha Particle X-ray Spectrometer'' detects alpha particles and X-rays, which provide information on the elemental composition of the comet's surface.<ref name="esa-apxs">{{Cite web |title=APXS |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/APXS |url-status=live |archive-url=https://web.archive.org/web/20230811092159/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/APXS |archive-date=11 August 2023 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref> The instrument is an improved version of the APXS on the [[Mars Pathfinder]].

; CIVA
:The ''Comet Nucleus Infrared and Visible Analyser''<ref name=bibringetal>{{cite journal |last1=Bibring |first1=Jean-Pierre |last2=Lamy |first2=P |last3=Langevin |first3=Y |last4=Souufflot |first4=A |last5=Berthé |first5=J |last6=Borg |first6=J |last7=Poulet |first7=F |last8=Mottola |first8=S |title=CIVA |journal=Space Science Reviews |date=2007 |volume=138 |issue=1–4 |pages=397–412 |doi=10.1007/s11214-006-9135-5 |bibcode=2007SSRv..128..397B }}</ref> (sometimes given as ÇIVA<ref name=bieleulamec>{{cite journal |title=Capabilities of Philae, the Rosetta Lander |journal=Space Science Reviews |first1=J. |last1=Biele |first2=S. |last2=Ulamec |volume=138 |issue=1–4 |pages=275–289 |date=July 2008 |doi=10.1007/s11214-007-9278-z|bibcode=2008SSRv..138..275B |s2cid=120594802 }}</ref>) is a group of seven identical cameras used to take panoramic pictures of the surface plus a visible-light microscope and an infrared [[spectrometer]]. The panoramic cameras (CIVA-P) are arranged on the sides of the lander at 60° intervals: five mono imagers and two others making up a stereo imager.  Each camera has a 1024×1024 pixel CCD detector.<ref name="nssdc-civa">{{Cite web |title=Comet nucleus Infrared and Visible Analyser (CIVA) |url=https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=2004-006C-01 |url-status=live |archive-url=https://web.archive.org/web/20231112094834/https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=2004-006C-01 |archive-date=12 November 2023 |access-date=15 November 2014 |publisher=[[National Space Science Data Center]] |id=2004-006C-01 }}</ref> The microscope and spectrometer (CIVA-M) are mounted on the base of the lander, and are used to analyse the composition, texture and albedo (reflectivity) of samples collected from the surface.<ref name="esa-civa">{{Cite web |title=ÇIVA |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/CIVA |url-status=live |archive-url=https://web.archive.org/web/20221023122558/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/CIVA |archive-date=23 October 2022 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref>

; [[CONSERT]]
:The ''Comet Nucleus Sounding Experiment by Radiowave Transmission'' used electromagnetic wave propagation to determine the comet's internal structure. A [[radar]] on ''Rosetta'' transmitted a signal through the nucleus to be received by a detector on ''Philae''.<ref name="Kofman2007">{{cite journal |title=The Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT): A Short Description of the Instrument and of the Commissioning Stages |journal=Space Science Reviews |first1=W. |last1=Kofman |first2=A. |last2=Herique |first3=J.-P. |last3=Goutail |first4=T. |last4=Hagfors |first5=I. P. |last5=Williams |first6=E. |last6=Nielsen |first7=J.-P. |last7=Barriot |first8=Y. |last8=Barbin |first9=C. |last9=Elachi |first10=P. |last10=Edenhofer |first11=A.-C. |last11=Levasseur-Regourd |first12=D. |last12=Plettemeier |first13=G. |last13=Picardi |first14=R. |last14=Seu |first15=V. |last15=Svedhem |display-authors=5 |volume=128 |issue=1–4 |pages=413–432 |date=February 2007 |doi=10.1007/s11214-006-9034-9 |bibcode=2007SSRv..128..413K|s2cid=122123636 }}</ref><ref name="esa-consert">{{Cite web |title=CONSERT |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/CONSERT2 |url-status=live |archive-url=https://web.archive.org/web/20240113191937/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/CONSERT2 |archive-date=13 January 2024 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref>

; COSAC
:The ''Cometary Sampling and Composition'' instrument is a combined [[gas chromatograph]] and time-of-flight [[mass spectrometry|mass spectrometer]] to perform analysis of soil samples and determine the content of volatile components.<ref name="Gosmann2005">{{cite journal |title=COSAC Onboard Rosetta: A Bioastronomy Experiment for the Short-Period Comet 67P/Churyumov-Gerasimenko |journal=Astrobiology |first1=Fred |last1=Goesmann |first2=Helmut |last2=Rosenbauer |first3=Reinhard |last3=Roll |first4=Hermann |last4=Böhnhardt |volume=5 |issue=5 |pages=622–631 |date=October 2005 |doi=10.1089/ast.2005.5.622 |bibcode=2005AsBio...5..622G |pmid=16225435}}</ref><ref name="esa-cosac">{{Cite web |title=COSAC |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/COSAC |url-status=live |archive-url=https://web.archive.org/web/20221024120351/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/COSAC |archive-date=24 October 2022 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref>

; MUPUS
:The ''Multi-Purpose Sensors for Surface and Sub-Surface Science'' instrument measured the density, thermal and mechanical properties of the comet's surface.<ref name="esa-mupus">{{Cite web |title=MUPUS |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/MUPUS |url-status=live |archive-url=https://web.archive.org/web/20230818025511/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/MUPUS |archive-date=18 August 2023 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref>

; Ptolemy
:An instrument measuring [[stable isotope ratio]]s of key volatiles on the comet's nucleus.<ref name="Wright2007">{{cite journal |title=Ptolemy: An Instrument to Measure Stable Isotopic Ratios of Key Volatiles on a Cometary Nucleus |journal=Space Science Reviews |first1=I. P. |last1=Wright |first2=S. J. |last2=Barber |first3=G. H. |last3=Morgan |first4=A. D. |last4=Morse |first5=S. |last5=Sheridan |first6=D. J. |last6=Andrews |first7=J. |last7=Maynard |first8=D. |last8=Yau |first9=S. T. |last9=Evans |first10=M. R. |last10=Leese |first11=J. C. |last11=Zarnecki |first12=B. J. |last12=Kent |first13=N. R. |last13=Waltham |first14=M. S. |last14=Whalley |first15=S. |last15=Heys |first16=D. L. |last16=Drummond |first17=R. L. |last17=Edeson |first18=E. C. |last18=Sawyer |first19=R. F. |last19=Turner |first20=C. T. |last20=Pillinger |display-authors=5 |volume=128 |issue=1–4 |pages=363–381 |date=February 2007 |doi=10.1007/s11214-006-9001-5 |bibcode=2007SSRv..128..363W|s2cid=120458462 }}</ref><ref name="Andrews2006">{{Cite conference |last1=Andrews |first1=D. J. |last2=Barber |first2=S. J. |last3=Morse |first3=A. D. |last4=Sheridan |first4=S. |last5=Wright |first5=I. P. |last6=Morgan |first6=G. H. |display-authors=5 |date=March 2006 |title=''Ptolemy'': An Instrument aboard the Rosetta Lander Philae, to Unlock the Secrets of the Solar System |url=https://www.lpi.usra.edu/meetings/lpsc2006/pdf/1937.pdf |conference=37th Lunar and Planetary Science Conference |location=League City, Texas |publisher=[[Lunar and Planetary Institute]] |archive-url=https://web.archive.org/web/20231112094835/https://www.lpi.usra.edu/meetings/lpsc2006/pdf/1937.pdf |archive-date=12 November 2023 |conference-url=https://www.lpi.usra.edu/meetings/lpsc2006/ |url-status=live }}</ref> Parts of the instrument were manufactured by the Special Techniques Group at [[United_Kingdom_Atomic_Energy_Authority|UKAEA]].<ref>{{cite web |url=http://techtransfer.euro-fusion.eu/index.php/success-story-8/ |archive-url=https://web.archive.org/web/20230608160225/http://techtransfer.euro-fusion.eu/index.php/success-story-8/ |archive-date=8 June 2023 |title=Eurofusion Ptolemy acknowledgement |publisher=[[EUROfusion]] |access-date=10 November 2023}}</ref>

; ROLIS
:The ''Rosetta Lander Imaging System'' is a [[Charge-coupled device|CCD camera]] used to obtain high-resolution images during descent and stereo panoramic images of areas sampled by other instruments.<ref name="esa-rolis">{{Cite web |title=ROLIS |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/ROLIS |url-status=live |archive-url=https://web.archive.org/web/20221025091928/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/ROLIS |archive-date=25 October 2022 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref> The CCD detector consists of 1024×1024 pixels.<ref>{{cite web |url=http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=PHILAE%20%20%20-02 |archive-url=https://web.archive.org/web/20080921153032/http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=PHILAE%20%20%20-02 |url-status=dead |archive-date=21 September 2008 |title=Rosetta Lander Imaging System (ROLIS) |publisher=[[National Space Science Data Center]] |access-date=28 August 2014}}</ref>

; ROMAP
:The ''Rosetta Lander Magnetometer and Plasma Monitor'' is a [[magnetometer]] and [[Plasma (physics)|plasma]] sensor to study the nucleus's magnetic field and its interactions with the [[solar wind]].<ref name="esa-romap">{{Cite web |title=ROMAP |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/ROMAP |url-status=live |archive-url=https://web.archive.org/web/20221024120353/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/ROMAP |archive-date=24 October 2022 |access-date=26 August 2014 |publisher=[[European Space Agency]] }}</ref>

; SD2
:The ''Sampling, Drilling and Distribution'' system obtains soil samples from the comet and transfers them to the Ptolemy, COSAC, and CIVA instruments for in-situ analysis.<ref name="esa20140409">{{Cite web |last=Di Lizia |first=Pierluigi |date=9 April 2014 |title=Introducing SD2: Philae's Sampling, Drilling and Distribution instrument |url=https://blogs.esa.int/rosetta/2014/04/09/introducing-sd2-philaes-sampling-drilling-and-distribution-instrument/ |url-status=live |archive-url=https://web.archive.org/web/20230425165417/https://blogs.esa.int/rosetta/2014/04/09/introducing-sd2-philaes-sampling-drilling-and-distribution-instrument/ |archive-date=25 April 2023 |access-date=24 December 2014 |publisher=[[European Space Agency]] }}</ref> SD2 contains four primary subsystems: drill, ovens, carousel, and volume checker.<ref name="polimi-sd2">{{Cite web |title=Philae SD2 |url=http://www.aero.polimi.it/SD2/ |url-status=dead |archive-url=https://web.archive.org/web/20140810095421/http://www.aero.polimi.it/SD2/ |archive-date=10 August 2014 |access-date=11 August 2014 |publisher=[[Polytechnic University of Milan|Politecnico di Milano]] }}</ref><ref name="Marchesi2001">{{Cite conference |last1=Marchesi |first1=M. |last2=Campaci |first2=R. |last3=Magnani |first3=P. |last4=Mugnuolo |first4=R. |last5=Nista |first5=A. |last6=Olivier |first6=A. |last7=Re |first7=E. |display-authors=5 |date=September 2001 |title=Comet sample acquisition for ROSETTA lander mission |url=https://www.esmats.eu/esmatspapers/pastpapers/pdfs/2001/marchesi.pdf |conference=9th European Space Mechanisms and Tribology Symposium |location=Liège, Belgium |publisher=[[European Space Agency]] |bibcode=2001ESASP.480...91M |archive-url=https://web.archive.org/web/20240223071816/https://www.esmats.eu/esmatspapers/pastpapers/pdfs/2001/marchesi.pdf |archive-date=23 February 2024 |conference-url=https://www.esmats.eu/esmatspapers/completelist.php?whichYear=2001 |url-status=live }}</ref> The drill system, made of steel and titanium, is capable of drilling to a depth of {{convert|230|mm|abbr=on}}, deploying a probe to collect samples, and delivering samples to the ovens.<ref name="polimi-sd2-drillbox">{{Cite web |title=Drill Box |url=http://www.aero.polimi.it/SD2/?SD2:System_Overview:Drill_Box |url-status=dead |archive-url=https://web.archive.org/web/20140813061742/http://www.aero.polimi.it/SD2/?SD2:System_Overview:Drill_Box |archive-date=13 August 2014 |access-date=24 December 2014 |publisher=[[Polytechnic University of Milan|Politecnico di Milano]] }}</ref> There are a total of 26 platinum ovens to heat samples—10 medium temperature ovens at {{convert|180|C|F}} and 16 high temperature ovens at {{convert|800|C|F}}—and one oven to clear the drill bit for reuse.<ref name="polimi-sd2-ovens">{{Cite web |title=Ovens |url=http://www.aero.polimi.it/SD2/?SD2:System_Overview:Ovens |url-status=dead |archive-url=https://web.archive.org/web/20140812205838/http://www.aero.polimi.it/SD2/?SD2:System_Overview:Ovens |archive-date=12 August 2014 |access-date=11 August 2014 |publisher=[[Polytechnic University of Milan|Politecnico di Milano]] }}</ref> The ovens are mounted on a rotating [[carousel]] that delivers the active oven to the appropriate instrument.<ref name="polimi-sd2-carousel">{{Cite web |title=Carousel |url=http://www.aero.polimi.it/SD2/?SD2:System_Overview:Carousel |url-status=dead |archive-url=https://web.archive.org/web/20140813015641/http://www.aero.polimi.it/SD2/?SD2:System_Overview:Carousel |archive-date=13 August 2014 |access-date=24 December 2014 |publisher=[[Polytechnic University of Milan|Politecnico di Milano]] }}</ref> The electromechanical volume checker determines how much material was deposited into an oven, and may be used to evenly distribute material on CIVA's optical windows.<ref name="polimi-sd2-vc">{{Cite web |title=Volume Checker |url=http://www.aero.polimi.it/SD2/?SD2:System_Overview:Volume_Checker |url-status=dead |archive-url=https://web.archive.org/web/20140813021610/http://www.aero.polimi.it/SD2/?SD2:System_Overview:Volume_Checker |archive-date=13 August 2014 |access-date=24 December 2014 |publisher=[[Polytechnic University of Milan|Politecnico di Milano]] }}</ref> Development of SD2 was led by the [[Italian Space Agency]] with contributions by prime contractor [[Selex ES|Tecnospazio S.p.A.]] (now Selex ES S.p.A.) in charge of the system design and overall integration; the Italian company Tecnomare S.p.A., owned by [[Eni|Eni S.p.A.]], in charge of the design, development, and testing of the drilling/sampling tool and  the volume checker; [[Media Lario]]; and [[Dallara]].<ref name="Marchesi2001" /> The instrument's principal investigator is Amalia Ercoli-Finzi ([[Politecnico di Milano]]).<ref name="repubb20141112">{{Cite news |date=12 November 2014 |title=Rosetta, anche l'Italia sbarca sulla cometa |url=https://www.repubblica.it/scienze/2014/11/12/news/e_anche_l_italia_sbarca_sulla_cometa-100393267/ |url-status=live |archive-url=https://web.archive.org/web/20231112094836/https://www.repubblica.it/scienze/2014/11/12/news/e_anche_l_italia_sbarca_sulla_cometa-100393267/ |archive-date=12 November 2023 |access-date=24 December 2014 |work=[[La Repubblica]] |language=it }}</ref>

; SESAME
:The ''Surface Electric Sounding and Acoustic Monitoring Experiments'' used three instruments to measure properties of the comet's outer layers. The ''Cometary Acoustic Sounding Surface Experiment'' (CASSE) measures the way in which sound travels through the surface. The ''Permittivity Probe'' (PP) investigates its electrical characteristics, and the ''Dust Impact Monitor'' (DIM) measures dust falling back to the surface.<ref name="Seidensticker2007">{{cite journal |title=Sesame – An Experiment of the Rosetta Lander Philae: Objectives and General Design |journal=Space Science Reviews |first1=K. J. |last1=Seidensticker |first2=D. |last2=Möhlmann |first3=I. |last3=Apathy |first4=W. |last4=Schmidt |first5=K. |last5=Thiel |first6=W. |last6=Arnold |first7=H.-H. |last7=Fischer |first8=M. |last8=Kretschmer |first9=D. |last9=Madlener |first10=A. |last10=Péter |first11=R. |last11=Trautner |first12=S. |last12=Schieke |display-authors=5 |volume=128 |issue=1–4 |pages=301–337 |date=February 2007 |doi=10.1007/s11214-006-9118-6 |bibcode=2007SSRv..128..301S|s2cid=119567565 }}</ref>

==Analysis of comet==
On 28 October 2020, it was reported that Philae had discovered, among other things, "low-strength primitive ice inside cometary boulders."<ref name=reportsofdiscovery /> This also included primitive water ice from the comet's estimated formation 4.5 billion years prior.<ref name=reportsofdiscovery /> This occurred primarily at the site of Philae's second touchdown onto the 67P/Churyumov–Gerasimenko, where the spacecraft successfully produced four distinct surface contacts on two adjoining cometary boulders.<ref name=reportsofdiscovery /> Philae was also able to drill {{convert|25|cm|in}} into the comet's boulder ice.<ref name=reportsofdiscovery />

== International contributions ==
;Austria
:The [[Institut für Weltraumforschung (Space Research Institute)|Austrian Space Research Institute]] developed the lander's anchor and two sensors within MUPUS, which are integrated into the anchor tips.<ref name="iwf-rosetta">{{Cite web |date=8 June 2014 |title=Rosetta |url=http://www.iwf.oeaw.ac.at/index.php?id=169&L=1 |url-status=dead |archive-url=https://web.archive.org/web/20150402091157/http://www.iwf.oeaw.ac.at/index.php?id=169&L=1 |archive-date=2 April 2015 |access-date=1 December 2014 |publisher=[[Institut für Weltraumforschung (Space Research Institute)|Institut für Weltraumforschung]] |language=de }}</ref>

;Belgium
:The [[Belgian Institute for Space Aeronomy]] (BIRA) cooperated with different partners to build one of the sensors (DFMS) of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument.<ref name="beinspace-20141106">{{Cite news |last=Christiaens |first=Kris |date=6 November 2014 |title=België mee aan boord van Rosetta kometenjager |url=https://www.belgiuminspace.be/nieuws/ruimtevaartprojecten/belgie-mee-aan-boord-van-rosetta-kometenjager |url-status=live |archive-url=https://web.archive.org/web/20231130135709/https://www.belgiuminspace.be/nieuws/ruimtevaartprojecten/belgie-mee-aan-boord-van-rosetta-kometenjager |archive-date=30 November 2023 |access-date=13 November 2014 |work=Belgium in Space |language=nl }}</ref><ref name="beinspace-20091113">{{Cite news |last=Christiaens |first=Kris |date=19 July 2009 |title=Rosetta |url=https://www.belgiuminspace.be/artikelen/ruimtevaartprojecten/planetaire-missies/rosetta |url-status=live |archive-url=https://web.archive.org/web/20231112094837/https://www.belgiuminspace.be/artikelen/ruimtevaartprojecten/planetaire-missies/rosetta |archive-date=12 November 2023 |access-date=13 November 2014 |work=Belgium in Space |language=nl }}</ref> The [[Belgian Institute for Space Aeronomy]] (BIRA) and [[Royal Observatory of Belgium]] (ROB) provided information about the [[space weather]] conditions at Rosetta to support the landing of Philae. The main concern was [[Solar particle event|solar proton events]].<ref name="esablog-20141112b">{{Cite web |last=Scuka |first=Daniel |date=12 November 2014 |title=Space weather report for Rosetta |url=https://blogs.esa.int/rocketscience/2014/11/12/space-weather-report-for-rosetta/ |url-status=live |archive-url=https://web.archive.org/web/20231112155443/https://blogs.esa.int/rocketscience/2014/11/12/space-weather-report-for-rosetta/ |archive-date=12 November 2023 |access-date=19 November 2014 |publisher=[[European Space Agency]] }}</ref>

;Canada
:Two Canadian companies played a role in the mission. [[SED Systems]], located on the [[University of Saskatchewan]] campus in Saskatoon, built three ground stations that were used to communicate with the ''Rosetta'' spacecraft.<ref name="USask">{{Cite news |date=13 November 2014 |title=Two Canadian Firms Play Small but Key Roles in Comet Landing |url=http://www.macleans.ca/uncategorized/two-canadian-firms-play-small-but-key-roles-in-comet-landing |url-status=dead |archive-url=https://web.archive.org/web/20141201072219/http://www.macleans.ca/uncategorized/two-canadian-firms-play-small-but-key-roles-in-comet-landing/ |archive-date=1 December 2014 |access-date=16 November 2014 |publisher=Maclean's |agency=The Canadian Press }}</ref> ADGA-RHEA Group of Ottawa provided MOIS (Manufacturing and Operating Information Systems) software which supported the procedures and command sequences operations software.<ref name="ADGA">{{cite press release |url=http://www.adga.ca/rosetta/en/media-release.html |title=Rosetta "The Comet Chaser" – The Canadian Connection |publisher=ADGA Group |date=13 November 2014 |access-date=16 November 2014 |url-status=dead |archive-url=https://web.archive.org/web/20141129033002/http://www.adga.ca/rosetta/en/media-release.html |archive-date=29 November 2014  }}</ref>

;Finland
:The [[Finnish Meteorological Institute]] provided the memory of the Command, Data and Management System (CDMS) and the Permittivity Probe (PP).<ref name="fmi-20141112">{{Cite press release |date=12 November 2014 |title=Lander successfully touches down on the comet surface |url=https://en.ilmatieteenlaitos.fi/press-release/29239004 |url-status=live |archive-url=https://archive.today/20141123141226/http://en.ilmatieteenlaitos.fi/press-release/29239004 |archive-date=23 November 2014 |access-date=23 November 2014 |publisher=[[Finnish Meteorological Institute]] }}</ref>

;France
:The [[CNES|French Space Agency]], in collaboration with various French scientific institutes (IAS, SA, LPG, LISA), provided the system's overall engineering, radiocommunications, battery assembly, CONSERT, CIVA and the [[ground segment]] (overall engineering and development/operation of the Scientific Operation & Navigation Centre).<ref name=dlrPdf />

;Germany
:The [[German Aerospace Center|German Space Agency]] (DLR) has provided the structure, thermal subsystem, flywheel, the Active Descent System (procured by DLR but made in Switzerland),<ref name="moog">{{cite web |url=http://www.moog.com/literature/Space_Defense/Spacecraft/Propulsion/active_descent_system.pdf |title=Active Descent System |publisher=[[Moog Inc.]] |access-date=11 November 2014 |archive-url=https://web.archive.org/web/20141112012855/http://www.moog.com/literature/Space_Defense/Spacecraft/Propulsion/active_descent_system.pdf |archive-date=12 November 2014 |url-status=dead }}</ref> ROLIS, downward-looking camera, SESAME, acoustic sounding and seismic instrument for ''Philae''. It has also managed the project and did the level product assurance. The [[University of Münster]] built MUPUS (it was designed and built in Space Research Centre of Polish Academy of Sciences<ref name="wawpl2014" />) and the [[Braunschweig University of Technology]] the ROMAP instrument. The [[Max Planck Institute for Solar System Research]] made the payload engineering, eject mechanism, landing gear, anchoring harpoon, central computer, COSAC, APXS and other subsystems. The institute has led development and construction of COSAC and DIM, a part of SESAME, as well as contributed to the deveplopment and construction of ROMAP.<ref name="mpg-rosetta">{{Cite web |title=MPS-Beteiligungen |url=https://www.mps.mpg.de/rosetta/mps-beteiligungen |url-status=live |archive-url=https://web.archive.org/web/20231112094839/https://www.mps.mpg.de/rosetta/mps-beteiligungen |archive-date=12 November 2023 |publisher=[[Max Planck Institute for Solar System Research]] |language=de }}</ref>

;Hungary
:The Command and Data Management Subsystem (CDMS) designed in the Wigner Research Centre for Physics of the [[Hungarian Academy of Sciences]] jointly with the Space and Ground Facilities Ltd. (a spin-off company of the Wigner Research Centre for Physics).<ref>{{cite web|url=http://wigner.mta.hu/node/934 |title=12 November, 2014 A Space Probe landed on the Surface of a Comet for the first time in Space Research |publisher=Wigner Research Centre for Physics |date=14 November 2014 |archive-url=https://web.archive.org/web/20160303235908/http://wigner.mta.hu/node/934 |archive-date=3 March 2016 |url-status=dead }}</ref><ref>{{Cite web |title=CDMS |url=http://www.sgf.hu/newsgfweb3_005.htm |url-status=live |archive-url=https://web.archive.org/web/20231228004545/http://www.sgf.hu/newsgfweb3_005.htm |archive-date=28 December 2023 |access-date=31 January 2017 |publisher=SGF Ltd. }}</ref> The Power Subsystem (PSS) designed in the Department of Broadband Infocommunications and Electromagnetic Theory at Budapest University of Technology and Economics.<ref>{{cite web|url=http://hvt.bme.hu/srg/references.html |title=References |publisher=Space Research Group |date=2013 |archive-url=https://web.archive.org/web/20160304223021/http://hvt.bme.hu/srg/references.html |archive-date=4 March 2016 |url-status=dead }}</ref> CDMS is the fault tolerant central computer of the lander, while PSS assures that the power coming from the batteries and solar arrays are properly handled, controls battery charging and manages the onboard power distribution.

;Ireland
:Captec Ltd., based in [[Malahide]], provided the independent validation of mission critical software (independent software validation facility or SVF)<ref name="esa-rosetta-industry">{{Cite web |date=24 June 2014 |title=Industrial Involvement in the Rosetta Mission |url=https://sci.esa.int/web/rosetta/-/54180-industrial-involvement-in-the-rosetta-mission |url-status=live |archive-url=https://web.archive.org/web/20231204232846/https://sci.esa.int/web/rosetta/-/54180-industrial-involvement-in-the-rosetta-mission |archive-date=4 December 2023 |access-date=7 February 2015 |publisher=[[European Space Agency]] }}</ref> and developed the software for the communications interface between the orbiter and the lander. Captec also provided engineering support to the prime contractor for the launch activities at Kourou.<ref name="ent-eire">{{Cite web |date=17 January 2014 |title=Comet chaser 'Rosetta' has technology from 2 Irish companies on board |url=http://newsletter.enterprise-ireland.com/1k4c98by6fv |url-status=live |archive-url=https://web.archive.org/web/20231112094836/http://newsletter.enterprise-ireland.com/1k4c98by6fv |archive-date=12 November 2023 |access-date=7 February 2015 |publisher=Enterprise Ireland }}</ref><ref>{{cite web |url=http://www.rte.ie/news/player/2014/0120/20509021-captecs-fred-kennedy-explains-its-role-in-the-rosetta-project/ |title=CAPTEC's Fred Kennedy explains its role in the Rosetta Project |publisher=RTE News |date=20 January 2014 |access-date=7 February 2014}}</ref> Space Technology Ireland Ltd. at [[Maynooth University]] has designed, constructed and tested the Electrical Support System Processor Unit (ESS) for the Rosetta mission. ESS stores, transmits and provides decoding for the command streams passing from the spacecraft to the lander and handles the data streams coming back from the scientific experiments on the lander to the spacecraft.<ref name="maynooth-rosetta">{{Cite press release |date=12 November 2014 |title=Maynooth University scientists play key role in historic Rosetta mission |url=https://www.maynoothuniversity.ie/news-events/maynooth-university-scientists-play-key-role-historic-rosetta-mission |url-status=live |archive-url=https://web.archive.org/web/20231112094926/https://www.maynoothuniversity.ie/news-events/maynooth-university-scientists-play-key-role-historic-rosetta-mission |archive-date=12 November 2023 |access-date=20 November 2014 |publisher=[[Maynooth University]] }}</ref>

;Italy
:The [[Italian Space Agency]] (ASI) developed the SD2 instrument and the photovoltaic assembly. Italian [[Thales Alenia Space|Alenia Space]] was involved in the assembly, integration and testing of the probe, as well as several mechanical and electrical ground support equipment. The company also built the probe's [[S-band]] and [[X-band]] digital transponder, used for communications with Earth.<ref name="farnesina-rosetta">{{Cite press release |date=13 November 2014 |title=Rosetta Mission: Italy's decisive technological contribution |url=http://www.esteri.it/MAE/EN/Sala_Stampa/ArchivioNotizie/Approfondimenti/2014/11/20141113_missrosetta.htm |url-status=live |archive-url=https://web.archive.org/web/20141129073612/http://www.esteri.it/MAE/EN/Sala_Stampa/ArchivioNotizie/Approfondimenti/2014/11/20141113_missrosetta.htm |archive-date=29 November 2014 |access-date=20 November 2014 |publisher=[[Ministry of Foreign Affairs (Italy)|Italian Ministry of Foreign Affairs and International Cooperation]] }}</ref>

;Netherlands
:Moog Bradford (Heerle, The Netherlands) provided the Active Descent System, which guided and propelled the lander down to its landing zone. To accomplish the ADS, a strategic industrial team was formed with Bleuler-Baumer Mechanik in Switzerland.<ref name="moog" />

;Poland
:The [[Space Research Centre]] of the [[Polish Academy of Sciences]] built the Multi-Purpose Sensors for Surface and Subsurface Science (MUPUS).<ref name="wawpl2014">{{cite web |url=http://mechatronics.cbk.waw.pl/en/projects/the-mupus-instrument-for-rosetta-mission-to-comet-churyumov-gerasimenko |title=The MUPUS Instrument for Rosetta mission to comet Churyumov-Gerasimenko |publisher=Laboratorium Mechatroniki i Robotyki Satelitarnej |year=2014 |archive-url=https://web.archive.org/web/20140102201326/http://mechatronics.cbk.waw.pl/en/projects/the-mupus-instrument-for-rosetta-mission-to-comet-churyumov-gerasimenko |archive-date=2 January 2014}}</ref>

;Spain
:The [[GMV Innovating Solutions|GMV]] Spanish division has been responsible for the maintenance of the calculation tools to calculate the criteria of lighting and visibility necessary to decide the point of landing on the comet, as well as the possible trajectories of decline of the ''Philae'' module. Other important Spanish companies or educational institutions that have been contributed are as follows: [[Instituto Nacional de Técnica Aeroespacial|INTA]], [[Airbus Defence and Space]] Spanish division, other small companies also participated in subcontracted packages in structural mechanics and thermal control like AASpace (former Space Contact),<ref name=aaspace>{{cite web |url=http://www.aaspace.eu |title=Presentación de PowerPoint – Space Activities |publisher=AASpace}}</ref> and the [[Universidad Politécnica de Madrid]].<ref name="dlr-all">{{Cite news |date=13 November 2014 |title=Tecnología española para aterrizar sobre un cometa |url=https://cincodias.elpais.com/cincodias/2014/11/12/tecnologia/1415814340_850362.html |url-status=live |archive-url=https://web.archive.org/web/20231112094916/https://cincodias.elpais.com/cincodias/2014/11/12/tecnologia/1415814340_850362.html |archive-date=12 November 2023 |access-date=11 November 2014 |work=[[Cinco Días]] |language=it }}</ref>

;Switzerland
:The [[Swiss Center for Electronics and Microtechnology|Swiss Centre for Electronics and Microtechnology]] developed CIVA.<ref name="CIVA Project">{{cite web |url=http://www.space-x.ch/?page_id=216 |title=CIVA Project |year=2014 |access-date=7 November 2014 |archive-url=https://web.archive.org/web/20141107225909/http://www.space-x.ch/?page_id=216 |archive-date=7 November 2014 |url-status=dead }}</ref>

;United Kingdom
:The [[Open University]] and the [[Rutherford Appleton Laboratory]] (RAL) developed PTOLEMY. RAL also constructed the blankets that kept the lander warm throughout its mission. [[Surrey Satellite Technology|Surrey Satellites Technology Ltd]]. (SSTL) constructed the [[reaction wheel|momentum wheel]] for the lander. It stabilised the module during the descent and landing phases.<ref name="dlrPdf" /> Manufacturer [[e2v]] supplied the CIVA and Rolis camera systems used to film the descent and take images of samples, as well as three other camera systems.<ref name="telegraph-20141111">{{Cite news |last=Tovey |first=Alan |date=11 November 2014 |title=UK space industry behind Rosetta comet mission |url=https://www.telegraph.co.uk/finance/newsbysector/industry/engineering/11221945/UK-space-industry-behind-Rosetta-comet-mission.html |url-status=live |archive-url=https://web.archive.org/web/20231211114512/https://www.telegraph.co.uk/finance/newsbysector/industry/engineering/11221945/UK-space-industry-behind-Rosetta-comet-mission.html |archive-date=11 December 2023 |newspaper=[[The Daily Telegraph|The Telegraph]] }}</ref>
<!--ref for all modules-->

== Media coverage ==
The landing was featured heavily in social media, with the lander having an official [[Twitter]] account portraying a [[personification]] of the spacecraft. The [[hashtag]] "#CometLanding" gained widespread traction. A [[Livestream]] of the control centres was set up, as were multiple official and unofficial events around the world to follow ''Philae''{{'s}} landing on Churyumov–Gerasimenko.<ref name="esa-20141112">{{Cite press release |date=12 November 2014 |title=Live updates: ''Rosetta'' mission comet landing |url=https://www.esa.int/Enabling_Support/Operations/Live_updates_Rosetta_mission_comet_landing |url-status=live |archive-url=https://web.archive.org/web/20230601003904/https://www.esa.int/Enabling_Support/Operations/Live_updates_Rosetta_mission_comet_landing |archive-date=1 June 2023 |publisher=[[European Space Agency]] }}</ref><ref name="esa-20141016">{{Cite press release |date=16 October 2014 |title=Call for Media Opportunities to follow Rosetta mission's historic comet landing |url=https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Call_for_Media_Opportunities_to_follow_Rosetta_mission_s_historic_comet_landing |url-status=live |archive-url=https://web.archive.org/web/20231112094844/https://www.esa.int/Science_Exploration/Space_Science/Rosetta/Call_for_Media_Opportunities_to_follow_Rosetta_mission_s_historic_comet_landing |archive-date=12 November 2023 |publisher=[[European Space Agency]] }}</ref> Various instruments on ''Philae'' were given their own Twitter accounts to announce news and science results.<ref name="bbcnews20141113">{{Cite news |last=Jackson |first=Patrick |date=13 November 2014 |title=Rosetta comet: One giant leap for Europe (not Nasa) |url=https://www.bbc.com/news/world-europe-30035699 |url-status=live |archive-url=https://web.archive.org/web/20231112094853/https://www.bbc.com/news/world-europe-30035699 |archive-date=12 November 2023 |access-date=2 January 2015 |work=[[BBC News]] }}</ref>

=== Popular culture ===
[[Vangelis]] composed the music for the trio of music videos released by ESA to celebrate the first-ever attempted soft landing on a comet by ESA's Rosetta mission.<ref>{{YouTube |FJrUnzLsmZk |"Arrival" by Vangelis}}</ref><ref>{{YouTube |W8bVOGN9jSg |"Philae's journey" by Vangelis}}</ref><ref>{{YouTube |PUpSVxoCcik |"Rosetta's waltz" by Vangelis}}</ref>

On 12 November 2014, the search engine [[Google]] featured a [[Google Doodle]] of ''Philae'' on its home page.<ref name="mirror-20141112">{{Cite news |last=Solon |first=Olivia |date=12 November 2014 |title=Philae: Google Doodle marks Rosetta's historic comet landing |url=https://www.mirror.co.uk/news/technology-science/science/philae-google-doodle-marks-rosettas-4617416 |url-status=live |archive-url=https://web.archive.org/web/20141113044743/http://www.mirror.co.uk/news/technology-science/science/philae-google-doodle-marks-rosettas-4617416 |archive-date=13 November 2014 |access-date=12 November 2014 |work=[[Daily Mirror]] }}</ref> On 31 December 2014, Google featured ''Philae'' again as part of its New Year's Eve 2014 Doodle.<ref name="idexpress-20141231">{{Cite news |last=Mukherjee |first=Trisha |date=31 December 2014 |title=Google doodle wraps up year in animated '2014 trending topics' |url=https://indianexpress.com/article/technology/technology-others/google-doodle-deflects-from-party-tradition-this-new-years-eve-its-2014-trending-topics/ |url-status=live |archive-url=https://web.archive.org/web/20231123053508/https://indianexpress.com/article/technology/technology-others/google-doodle-deflects-from-party-tradition-this-new-years-eve-its-2014-trending-topics/ |archive-date=23 November 2023 |access-date=30 January 2015 |work=[[The Indian Express]] }}</ref>

Online comic author [[Randall Munroe]] wrote a live updating strip on his website ''[[xkcd]]'' on the day of the landing.<ref name="xkcd-1446">{{Cite web |last=Randall |first=Munroe |author-link=Randall Munroe |date=12 November 2014 |title=Landing |url=https://xkcd.com/1446/ |url-status=live |archive-url=https://web.archive.org/web/20240211234100/https://xkcd.com/1446/ |archive-date=11 February 2024 |access-date=22 January 2014 |website=[[xkcd]] |id=1446 }}</ref><ref name="gizmodo-20141112">{{Cite news |last=Davis |first=Lauren |date=12 November 2014 |title=''xkcd'' Animates The Philae Comet Landing—And It's Adorable |url=https://gizmodo.com/xkcd-animates-the-philae-comet-landing-and-its-adorable-1658135493 |url-status=live |archive-url=https://web.archive.org/web/20231224171518/https://gizmodo.com/xkcd-animates-the-philae-comet-landing-and-its-adorable-1658135493 |archive-date=24 December 2023 |access-date=13 September 2015 |work=gizmodo }}</ref>

== See also ==
{{portal|Spaceflight}}
* ''[[Hayabusa]]''
* [[Hayabusa2#MASCOT|MASCOT]], DLR-CNES mini asteroid lander
* [[MINERVA (spacecraft)|MINERVA]]
* [[NEAR Shoemaker]]
* [[OSIRIS-REx]]
* [[Timeline of Rosetta spacecraft|Timeline of ''Rosetta'' spacecraft]]

== References ==
{{Reflist|30em}}

== Further reading ==
* {{cite journal |url=http://www.open.ac.uk/personalpages/a.j.ball/publications/online/capcom.html |title=Rosetta Lander |journal=CapCom |first=Andrew J. |last=Ball |volume=8 |issue=2 |date=November 1997}}
* {{cite conference |url=http://www.planetaryprobe.eu/IPPW7/proceedings/IPPW7%20Proceedings/Presentations/Session7B/pr395.pdf |title=From the Rosetta Lander ''Philae'' to an Asteroid Hopper: Lander Concepts For Small Bodies Missions |conference=7th International Planetary Probe Workshop. 14–18 June 2010. Barcelona, Spain. |first1=S. |last1=Ulamec |first2=J. |last2=Biele |date=January 2006}}

== External links ==
{{Commons category|Philae (spacecraft)}}
* [http://sci.esa.int/rosetta/ ''Rosetta'' mission website] by the [[European Space Agency]]
* [https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2004-006C ''Philae'' entry] at the [[National Space Science Data Center]]
* [http://www.mps.mpg.de/3053813/Philae-Blog ''Philae'' blog] at the [[Max Planck Institute for Solar System Research]]
* [https://pdssbn.astro.umd.edu/data_sb/missions/rosetta/index.shtml ''Rosetta Lander'' Mission Data Archive] at the NASA Planetary Data System, Small Bodies Node

;Media
* [https://www.youtube.com/watch?v=-77-Z_DHTlY ''The working of... Philae, the comet lander''] by the [[German Aerospace Center]]
* [http://www.esa.int/spaceinvideos/Videos/2014/11/Rosetta_landing_on_a_comet ''Rosetta: landing on a comet''] by the European Space Agency
* [https://www.flickr.com/photos/europeanspaceagency/sets/72157649192589446/ ESA's ''Philae'' landing gallery] at Flickr.com

{{Rosetta mission}}
{{Comet spacecraft}}
{{European Space Agency}}
{{Planetary defense}}
{{Solar System probes}}
{{Orbital launches in 2004}}
{{2014 in space}}
{{2016 in space}}

[[Category:Rosetta mission|2]]
[[Category:Attached spacecraft]]
[[Category:Landers (spacecraft)]]
[[Category:Derelict landers (spacecraft)]]
[[Category:Space probes launched in 2004]]
[[Category:Articles containing video clips]]