View source for Mira

{{short description|Binary star in the constellation Cetus}}
{{Other uses}}
{{Starbox begin
| name = Mira<ref name="IAU-CSN"/>
}}
{{Starbox image
 | image=
{{Location mark
|image=Cetus constellation map.svg|alt=|float=center|width=280
|label=|position=right
|mark=Red circle.svg|mark_width=12|mark_link=Mira
|x=325|y=330
}}
|caption=Location of Mira (circled)
}}
{{Starbox observe
| epoch       = [[J2000.0]]
| constell    = [[Cetus (constellation)|Cetus]]
| ra          = {{RA|02|19|20.79210}}<ref name=aaa474_2_653/>
| dec         = {{DEC|−02|58|39.4956}}<ref name=aaa474_2_653/>
| appmag_v    = 2.0 ''to'' 10.1<ref name="gcvs71"/>
}}
{{Starbox character
| class       = M7&nbsp;IIIe<ref name=aj114_1584/> {{nowrap|(M5e-M9e<ref name="gcvs71"/>)}}
| b-v         = +1.53<ref name="apj87"/>
| u-b         = +0.08<ref name="apj87"/>
| variable    = [[Mira variable|Mira]]<ref name="gcvs71"/>
}}
{{Starbox astrometry
| radial_v    = +63.8<ref name=rgcrv/>
| prop_mo_ra  = +9.33<ref name=aaa474_2_653/>
| prop_mo_dec = −237.36<ref name=aaa474_2_653/>
| parallax    = 10.91
| p_error     = 1.22
| parallax_footnote=<ref name=aaa474_2_653/>
| absmag_v    = +0.99<ref name=Anderson2012/> (variable)
}}
{{Starbox orbit
|reference=<ref name=Izmailov2025/>
|period={{Val|1590|560|fmt=commas}}
|axis={{Val|4.7|0.8}}
|eccentricity={{Val|0.98|0.16}}
|inclination={{Val|99|9}}
|node={{Val|84|18}}
|periastron={{Val|2026.8|10.9}}
|periarg={{val|83|11}}
}}
{{Starbox detail
| age_gyr     = 6<ref name=apj275/>
| metal_fe    =
| mass        = 1.18<ref name=apj275/>
| radius      = 332–402<ref name=aaa421/> 
| rotational_velocity =
| luminosity_bolometric = 8,400–9,360<ref name=aaa421/>
| temperature = 2,918–3,192<ref name=aaa421/>
}}
{{Starbox catalog
| names       = Stella Mira, Collum Ceti, Wonderful Star,<ref name=allen1963/> [[Bayer designation|ο]]&nbsp;Ceti, [[Flamsteed designation|68]]&nbsp;Ceti, [[Bonner Durchmusterung|BD]]−03°353, [[Henry Draper catalogue|HD]]&nbsp;14386, [[Hipparcos catalogue|HIP]]&nbsp;10826, [[Harvard Revised catalogue|HR]]&nbsp;681, [[Luyten Two-Tenths catalogue|LTT]]&nbsp;1179, [[Smithsonian Astrophysical Observatory|SAO]]&nbsp;129825
}}
{{Starbox reference
|Simbad=Mira
}}
{{Starbox end}}

'''Mira''' ({{IPAc-en|ˈ|m|aɪ|r|ə}}), designation '''Omicron Ceti''' ('''ο Ceti''', abbreviated '''Omicron Cet''', '''ο Cet'''), is a [[binary star]] in the [[constellation]] [[Cetus (constellation)|Cetus]]. The system consists of a variable red giant (Mira A) along with a [[white dwarf]] companion ([[Mira B]]). Mira A is a pulsating [[variable star]] and was the first non-[[supernova]] [[variable star]] discovered, with the possible exception of [[Algol]]. It is the prototype of the [[Mira variable]]s. The system lies at a distance of {{convert|300|ly|pc|abbr=off|lk=on}}.

==Nomenclature==
ο Ceti ([[Romanization of Greek|Latinised]] to ''Omicron Ceti'') is the star's [[Bayer designation]]. It was named Mira ([[Latin]] for 'wonderful' or 'astonishing') by [[Johannes Hevelius]] in his ''Historiola Mirae Stellae'' (1662). In 2016, the [[International Astronomical Union]] organized a [[Working Group on Star Names]] (WGSN)<ref name="WGSN"/> to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN, which included Mira for this star.<ref name="WGSN1"/>
[[File:MiraCC.jpg|thumb|Mira at two different times]]

==Observation history==
[[File:Mira light curve.png|thumb|left|upright=1.2|Visual [[light curve]] of Mira, generated using the [[AAVSO]] light curve generator tool{{full citation needed|date=December 2021}}]]
Evidence that the variability of Mira was known in [[History of China|ancient China]], [[Babylon]] or [[Ancient Greece|Greece]] is at best only circumstantial.<ref name=wilk/> What is certain is that the variability of Mira was recorded by the astronomer [[David Fabricius]] beginning on August 3, 1596. Observing what he thought was the planet [[Mercury (planet)|Mercury]] (later identified as [[Jupiter]]), he needed a reference star for comparing positions and picked a previously unremarked third-magnitude star nearby. By August 21, however, it had increased in brightness by one [[Apparent magnitude|magnitude]], then by October had faded from view. Fabricius assumed it was a nova, but then saw it again on February 16, 1609.<ref name=hr/>

In 1638 [[Johannes Phocylides Holwarda|Johannes Holwarda]] determined a period of the star's reappearances, eleven months; he is often credited with the discovery of Mira's variability. [[Johannes Hevelius]] was observing it at the same time and named it Mira in 1662, for it acted like no other known star. [[Ismail Bouillaud]] then estimated its period at 333 days, less than one day off the modern value of 332 days. Bouillaud's measurement may not have been erroneous: Mira is known to vary slightly in period, and may even be slowly changing over time. The star is estimated to be a six-billion-year-old [[red giant]].<ref name=apj275/>

[[File:Mira the star.jpg|thumb|left|Mira as seen from the Earth]]
There is considerable speculation as to whether Mira had been observed prior to Fabricius. Certainly [[Algol]]'s history (known for certain as a variable only in 1667, but with legends and such dating back to antiquity showing that it had been observed with suspicion for millennia) suggests that Mira might have been known, too. [[Karl Manitius]], a modern translator of [[Hipparchus]]' ''Commentary on Aratus'', has suggested that certain lines from that second-century text may be about Mira. The other pre-telescopic Western catalogs of [[Ptolemy]], [[al-Sufi]], [[Ulugh Beg]] and [[Tycho Brahe]] turn up no mentions, even as a regular star. There are three observations from Chinese and Korean archives, in 1596, 1070 and the same year when Hipparchus would have made his observation (134 BC) that are suggestive.{{citation needed|date=October 2017}}

An estimate obtained in 1925 from interferometry by [[Francis G. Pease]] at the [[Mount Wilson Observatory]] gave Mira a diameter of 250-260 million miles (402 to 418 million km, or approximately {{Solar radius|290-300|link=y}}), making it the then-second largest star known and comparable to historical estimates of [[Betelgeuse]],<ref>{{Cite journal |last=Pease |first=F. G. |date=1925 |title=The Diameter of Mira Ceti at the 1925 Maximum |url=https://www.jstor.org/stable/40693379 |journal=Publications of the Astronomical Society of the Pacific |volume=37 |issue=216 |pages=89–90 |jstor=40693379 |issn=0004-6280}}</ref> surpassed only by [[Antares]].<ref>{{Cite journal |date=1925 |title=Science News |url=https://www.jstor.org/stable/1650052 |journal=Science |volume=61 |issue=1576 |pages=x–xiv |jstor=1650052 |issn=0036-8075}}</ref> On the contrary, [[Otto Struve]] thought of Mira as a [[red supergiant]] with an approximate radius of {{Solar radius|500}}, while modern consensus accepts Mira to be a highly evolved [[asymptotic giant branch]] star.<ref>{{Cite book |url=http://archive.org/details/Galaxy_v23n06_1965-08 |title=Galaxy v23n06 (1965 08)}}</ref>

==Distance and background Information ==
Pre-''[[Hipparcos]]'' estimates centered on 220 [[light-year]]s;<ref name=burnham1980/> while Hipparcos data from the 2007 reduction suggest a distance of 299 light-years, with a [[margin of error]] of 11%.<ref name=aaa474_2_653/> The age of Mira is  suspected to be about 6 billion years old. Its gaseous material is scattered, as much as one-thousandth as thin as the air around us. Mira is also among the coolest known bright stars of the red giant class, with a temperature ranging from 3,000 to 4,000 degrees Fahrenheit (1,600 to 2,200 degrees Celsius). As with other long-period variables, Mira's deep red color at minimum pales to a lighter orange as the star brightens.  Within the next  few million years, Mira will discard its outer layers and become a planetary nebula, leaving behind a white dwarf.

==Stellar system==
This binary star system consists of a red giant (Mira, designated Mira A) undergoing mass loss and a high-temperature [[white dwarf]] companion (Mira B) that is accreting mass from the primary. Such an arrangement of stars is known as a symbiotic system and this is the closest such symbiotic pair to the [[Sun]]. Examination of this system by the [[Chandra X-ray Observatory]] shows a direct mass exchange along a bridge of matter from the primary to the white dwarf. The two stars are currently separated by about 70&nbsp;[[astronomical unit]]s.<ref name=aass304_1_379/>

===Component A===
[[File:Mira in UV and Visible Light.jpg|thumb|Mira in UV and visible light]]
Mira A is currently an [[asymptotic giant branch]] (AGB) star, in the thermally pulsing AGB phase.<ref name=pogge/><ref name=lopez/> Each pulse lasts a decade or more, and an amount of time on the order of 10,000&nbsp;years passes between each pulse. With every pulse cycle Mira increases in luminosity and the pulses grow stronger. This is also causing dynamic instability in Mira, resulting in dramatic changes in luminosity and size over shorter, irregular time periods.<ref name=deloore/>

The overall shape of Mira A has been observed to change, exhibiting pronounced departures from symmetry. These appear to be caused by bright spots on the surface that evolve their shape on time scales of 3–14 months. Observations of Mira A in the [[ultraviolet]] band by the [[Hubble Space Telescope]] have shown a plume-like feature pointing toward the companion star.<ref name=lopez/>

====Variability====
[[File:Mira 1997.jpg|thumb|left|Mira as seen by the [[Hubble Space Telescope]] in August 1997]]
Mira A is a [[variable star]], specifically the prototypical [[Mira variable]]. The 6,000 to 7,000 known stars of this class<ref>[https://web.archive.org/web/20201031181546/ftp://cdsarc.u-strasbg.fr/pub/cats/II/250/vartype.txt GCVS: vartype.txt] from the [[General Catalogue of Variable Stars|GCVS]] catalogue (statistics at the end of the file indicate 6,006 confirmed and 1,237 probable Mira variables)</ref> are all [[red giant]]s whose surfaces pulsate in such a way as to increase and decrease in brightness over periods ranging from about 80 to more than 1,000 days.

In the particular case of Mira, its increases in brightness take it up to about [[Apparent magnitude|magnitude]] 3.5 on average, placing it among the brighter [[List of stars in Cetus|stars in the Cetus constellation]]. Individual cycles vary too; well-attested maxima go as high as magnitude 2.0 in brightness and as low as 4.9, a range almost 15 times in brightness, and there are historical suggestions that the real spread may be three times this or more. Minima range much less, and have historically been between 8.6 and 10.1, a factor of four times in luminosity. The total swing in brightness from absolute maximum to absolute minimum (two events which did not occur on the same cycle) is 1,700 times. Mira emits the vast majority of its [[Solar irradiance|radiation]] in the [[infrared]], and its variability in that band is only about two magnitudes. The shape of its [[light curve]] is of an increase over about 100 days, and the return to minimum taking twice as long.<ref name=braune/> Contemporary approximate maxima for Mira:<ref name="seds" />
{{Div col|colwidth=10em}}
* Oct 21–31, 1999
* Sep 21–30, 2000
* Aug 21–31, 2001
* Jul 21–31, 2002
* Jun 21–30, 2003
* May 21–31, 2004
* Apr 11–20, 2005
* Mar 11–20, 2006
* Feb {{0}}1–10, 2007
* Jan 21–31, 2008
* Dec 21–31, 2008
* Nov 21–30, 2009
* Oct 21–31, 2010
* Sep 21–30, 2011
* Aug 27, 2012
* Jul 26, 2013
* May 12, 2014
* Apr 9, 2015
* Mar 6, 2016
* Jan 31, 2017
* Dec 29, 2017
* Nov 26, 2018
* Oct 24, 2019
* Sep 20, 2020
* Aug 18, 2021
* Jul 16, 2022
* Jun 13, 2023
* May 10, 2024
{{Div col end}}

[[File:Chi Cygni pulsations.png|thumb|upright=1.3|Pulsations in [[χ Cygni]], showing the relation between the visual light curve, temperature, radius and luminosity typical of [[Mira variable]] stars]]
From northern temperate latitudes, Mira is generally not visible between late March and June due to its proximity to the Sun. This means that at times several years can pass without it appearing as a naked-eye object.

The pulsations of Mira variables cause the star to expand and contract, but also to change its temperature. The temperature is highest slightly after the visual maximum, and lowest slightly before minimum. The photosphere, measured at the [[Rosseland radius]], is smallest just before visual maximum and close to the time of maximum temperature. The largest size is reached slightly before the time of lowest temperature. The [[bolometric luminosity]] is [[Stefan–Boltzmann law|proportional to the fourth power]] of the temperature and the square of the radius, but the radius varies by over 20% and the temperature by less than 10%.<ref name=lacour>{{cite journal|bibcode=2009ApJ...707..632L|arxiv=0910.3869|title=The Pulsation of χ Cygni Imaged by Optical Interferometry: A Novel Technique to Derive Distance and Mass of Mira Stars|journal=The Astrophysical Journal|volume=707|issue=1|pages=632–643|last1=Lacour|first1=S.|last2=Thiébaut|first2=E.|last3=Perrin|first3=G.|last4=Meimon|first4=S.|last5=Haubois|first5=X.|last6=Pedretti|first6=E.|last7=Ridgway|first7=S. T.|last8=Monnier|first8=J. D.|last9=Berger|first9=J. P.|last10=Schuller|first10=P. A.|last11=Woodruff|first11=H.|last12=Poncelet|first12=A.|last13=Le Coroller|first13=H.|last14=Millan-Gabet|first14=R.|last15=Lacasse|first15=M.|last16=Traub|first16=W.|year=2009|doi=10.1088/0004-637X/707/1/632|s2cid=28966631}}</ref>

In Mira, the highest luminosity occurs close to the time when the star is hottest and smallest. The visual magnitude is determined both by the luminosity and by the proportion of the [[Electromagnetic radiation|radiation]] that occurs at visual wavelengths. Only a small proportion of the radiation is emitted at visual wavelengths and this proportion is very strongly influenced by the temperature ([[Planck's law]]). Combined with the [[bolometric luminosity|overall luminosity]] changes, this creates the very big [[visual magnitude]] variation with the maximum occurring when the temperature is high.<ref name=aaa421/>

[[Infrared]] [[VLTI]] measurements of Mira at [[phase (waves)|phases]] 0.13, 0.18, 0.26, 0.40 and 0.47, show that the radius varies from {{val|332|38|u={{solar radius|link=y}}}} at phase 0.13 just after maximum to {{val|402|46|u={{solar radius}}}} at phase 0.40 approaching minimum. The temperature at phase 0.13 is {{val|3192|200|ul=K|fmt=commas}} and {{val|2918|183|u=K|fmt=commas}} at phase 0.26 about halfway from maximum to minimum. The luminosity is calculated to be {{val|9360|3140|u={{solar luminosity|link=y}}|fmt=commas}} at phase 0.13 and {{val|8400|2820|u={{solar luminosity}}|fmt=commas}} at phase 0.26.<ref name=aaa421/>

The pulsations of Mira have the effect of expanding its photosphere by around 50% compared to a non-pulsating star. In the case of Mira, if it was not pulsating it is modelled to have a radius of only around {{solar radius|240}}.<ref name=aaa421/>

====Mass loss====
Ultraviolet studies of Mira by [[NASA]]'s Galaxy Evolution Explorer ([[GALEX]]) space telescope have revealed that it sheds a trail of material from the outer envelope, leaving a tail 13 light-years in length, formed over tens of thousands of years.<ref name=martin/><ref name=minkel/> It is thought that a hot [[Bow shock|bow wave]] of compressed plasma/gas is the cause of the tail; the bow wave is a result of the interaction of the stellar wind from Mira A with gas in interstellar space, through which Mira is moving at an extremely high speed of {{Convert|130|km/s|mph|abbr=off}}.<ref name=wareing2007/> The tail consists of material stripped from the head of the bow wave, which is also visible in ultraviolet observations. Mira's bow shock will eventually evolve into a [[planetary nebula]], the form of which will be considerably affected by the motion through the [[interstellar medium]] (ISM).<ref name=wareing/> Mira’s tail offers a unique opportunity to study how stars like the Sun die and ultimately seed new [[planetary system]]s. As Mira hurls along, its tail drops off carbon, oxygen and other important elements needed for new stars, planets, and possibly even life to form. This tail material, visible now for the first time, has been shed over the past 30,000 years.

[[File:Mira the star-by Nasa alt crop.jpg|thumb|699px|center|Ultraviolet mosaic of Mira's bow shock and tail obtained using NASA's Galaxy Evolution Explorer ([[GALEX]])]]

===Component B===
{{Main|Mira B}}

The companion star is {{val|0.487|0.006|ul=arcseconds}} away from the main star.<ref name=ramstedt2014>{{cite journal |bibcode=2014A&A...570L..14R |title=The wonderful complexity of the Mira AB system |last1=Ramstedt |first1=S. |last2=Mohamed |first2=S. |last3=Vlemmings |first3=W. H. T. |last4=Maercker |first4=M. |last5=Montez |first5=R. |last6=Baudry |first6=A. |last7=De Beck |first7=E. |last8=Lindqvist |first8=M. |last9=Olofsson |first9=H. |last10=Humphreys |first10=E. M. L. |last11=Jorissen |first11=A. |last12=Kerschbaum |first12=F. |last13=Mayer |first13=A. |last14=Wittkowski |first14=M. |last15=Cox |first15=N. L. J. |last16=Lagadec |first16=E. |last17=Leal-Ferreira |first17=M. L. |last18=Paladini |first18=C. |last19=Pérez-Sánchez |first19=A. |last20=Sacuto |first20=S. |journal=Astronomy and Astrophysics |year=2014 |volume=570 |pages=L14 |doi=10.1051/0004-6361/201425029 |arxiv=1410.1529 |s2cid=55554110 }}</ref> It was resolved by the [[Hubble Space Telescope]] in 1995, when it was 70 [[astronomical unit]]s from the primary; and results were announced in 1997. The HST ultraviolet images and later X-ray images by the [[Chandra X-ray Observatory|Chandra space telescope]] show a spiral of gas rising off Mira in the direction of Mira B. The companion's [[orbital period]] around Mira is approximately 497.9 years.<ref>{{cite journal |last1=Prieur |first1=J. L. |last2=Aristidi |first2=E. |last3=Lopez |first3=B. |last4=Scardia |first4=M. |last5=Mignard |first5=F. |last6=Carbillet |first6=M. |title=High Angular Resolution Observations of Late‐Type Stars |journal=The Astrophysical Journal Supplement Series |date=March 2002 |volume=139 |issue=1 |pages=249–258 |doi=10.1086/338029}}</ref>

In 2007, observations showed a [[protoplanetary disc]] around the companion, Mira B. This disc is being accreted from material in the [[Stellar wind|solar wind]] from Mira and could eventually form new planets. These observations also hinted that the companion was a [[main-sequence star]] of around 0.7 [[solar mass]] and [[spectral type]] K, instead of a white dwarf as originally thought.<ref name=mirab/> However, in 2010 further research indicated that Mira B is, in fact, a white dwarf.<ref name=sokoloski/>

==References==
{{Reflist|refs=

<ref name="WGSN1">{{cite web | url=http://www.pas.rochester.edu/~emamajek/WGSN/WGSN_bulletin1.pdf | title=Bulletin of the IAU Working Group on Star Names, No. 1 |access-date=28 July 2016}}</ref>

<ref name=Anderson2012>{{citation
 | title=XHIP: An extended hipparcos compilation
 | last1=Anderson | first1=E. | last2=Francis | first2=Ch.
 | journal=Astronomy Letters
 | volume=38 | issue=5 | pages=331 | year=2012
 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015
 | arxiv=1108.4971 | s2cid=119257644 | postscript=. }}</ref>

<ref name="WGSN">{{cite web | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | title=IAU Working Group on Star Names (WGSN) | access-date=22 May 2016 | archive-date=23 April 2020 | archive-url=https://web.archive.org/web/20200423144448/https://www.iau.org/science/scientific_bodies/working_groups/280/ | url-status=dead }}</ref>

<ref name=wilk>{{cite journal | last=Wilk | first=Stephen R | title=Mythological Evidence for Ancient Observations of Variable Stars | journal=The Journal of the American Association of Variable Star Observers | date=1996 | volume=24 | issue=2 | pages=129–133 | bibcode=1996JAVSO..24..129W }}</ref>

<ref name=hr>{{Cite journal|bibcode=1997JAVSO..25..115H|title=History of the Discovery of Mira Stars|journal=The Journal of the American Association of Variable Star Observers|volume=25|issue=2|pages=115|last1=Hoffleit|first1=Dorrit|year=1997}}</ref>

<ref name=burnham1980>{{Cite book| first1=Robert Jr. | last1=Burnham | title=Burnham's Celestial Handbook | volume=1 | location=New York | publisher=Dover Publications Inc. | date=1980 | page=634}}</ref>

<ref name=aass304_1_379>{{cite journal
 | last=Karovska | first=Margarita
 | title=Future Prospects for Ultra-High Resolution Imaging of Binary Systems at UV and X-rat Wavelengths
 | series=304
 | issue=1–4
 | journal=Astrophysics and Space Science | volume=304 | pages=379–382 |date=August 2006 | doi=10.1007/s10509-006-9146-4
 | bibcode=2006Ap&SS.304..379K | s2cid=124913393
 }}</ref>

<ref name=pogge>{{cite web | last=Pogge | first=Richard | date=January 21, 2006 | url=http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit2/lowmass.html | title=Lecture 16: The Evolution of Low-Mass Stars | publisher=Ohio State University | access-date=2007-12-11 }}</ref>

<ref name=Izmailov2025>{{Cite journal |last=Izmailov |first=Igor |last2=Khovritchev |first2=Maxim |date=January 2025 |title=New Orbital Parameters of 850 Wide Visual Binary Stars and Their Statistical Properties |journal=Research in Astronomy and Astrophysics |language=en |volume=25 |issue=1 |pages=015016 |doi=10.1088/1674-4527/ad9da3 |bibcode=2025RAA....25a5016I  |issn=1674-4527}}</ref>

<ref name=deloore>{{cite book | first=C. W. H. | last=De Loore |author2=Doom, C | date=1992 | title=Structure and Evolution of Single and Binary Stars | publisher=Springer | isbn=0-7923-1768-8 }}</ref>

<ref name=lopez>{{cite conference | last=Lopez | first=B. | title=AGB and post-AGB stars at high angular resolution | conference =Proceedings IAU Symposium #191: Asymptotic Giant Branch Stars | date=1999 | pages=409 | bibcode=1999IAUS..191..409L }}</ref>

<ref name=braune>{{Cite web|last=Braune |first=Werner |title=Bundesdeutsche Arbeitsgemeinschaft für Veränderliche Sterne |url=http://www.bav-astro.de/index_e.html |access-date=2007-08-16 |archive-url=https://web.archive.org/web/20070810065942/http://www.bav-astro.de/index_e.html |archive-date=2007-08-10 |url-status=dead }}</ref>

<ref name=seds>{{cite web|url=http://spider.seds.org/spider/Vars/mira.html|title = SEDS - Mira|access-date=2017-11-19}}</ref>

<ref name=minkel>{{cite journal|title=Shooting Bullet Star Leaves Vast Ultraviolet Wake| last1=Minkel|first1=JR.|journal=Scientific American|date=2007}}</ref>

<ref name=martin>{{cite journal |journal=Nature |volume=448 |title=A turbulent wake as a tracer of 30,000 years of Mira's mass loss history |date=August 17, 2007 |pages=780–783 |pmid=17700694
|last1=Martin |first1=D. Christopher |last2=Seibert |first2=M |last3=Neill |first3=JD |last4=Schiminovich |first4=D |last5=Forster |first5=K |last6=Rich |first6=RM |last7=Welsh |first7=BY |last8=Madore |first8=BF |last9=Wheatley |first9=JM |last10=Morrissey |first10=P |last11=Barlow |first11=TA |issue=7155 |bibcode=2007Natur.448..780M |doi=10.1038/nature06003 |s2cid=4426573 |url=https://authors.library.caltech.edu/55875/2/nature06003-s1.pdf }}</ref>

<ref name=wareing2007>{{cite journal | url=http://www.iop.org/EJ/article/1538-4357/670/2/L125/22252.html|last1=Wareing|first1=Christopher| journal=Astrophysical Journal Letters|volume=670|issue=2|title=It's a wonderful tail: the mass-loss history of Mira|doi= 10.1086/524407|date=November 6, 2007|pages=L125–L129|last2=Zijlstra|first2=A. A.|last3=O'Brien|first3=T. J.|last4=Seibert|first4=M.|bibcode=2007ApJ...670L.125W|arxiv = 0710.3010 |s2cid=16954556}}</ref>

<ref name=wareing>{{cite journal | last=Wareing | first=Christopher | journal=Philosophical Transactions of the Royal Society A | volume=366 | issue=1884 | title=Wonderful Mira | doi=10.1098/rsta.2008.0167 | pmid=18812301 | date=December 13, 2008 | pages=4429–4440|bibcode = 2008RSPTA.366.4429W | s2cid=29910377 | url=http://eprints.whiterose.ac.uk/83151/7/ms.pdf }}</ref>

<ref name=sokoloski>{{Cite journal|arxiv=1009.2509v1 |author1=Sokoloski |author2=Lars Bildsten |title=Evidence for the White Dwarf Nature of Mira B |journal=The Astrophysical Journal |volume=723 |issue=2 |pages=1188–1194 |date=2010|doi=10.1088/0004-637X/723/2/1188 |bibcode=2010ApJ...723.1188S|s2cid=119247560 }}</ref>

<ref name=mirab>{{Cite journal|bibcode=2007ApJ...662..651I|arxiv=astro-ph/0703244|title=Born-Again Protoplanetary Disk around Mira B|journal=The Astrophysical Journal|volume=662|issue=1|pages=651–657|last1=Ireland|first1=M. J.|last2=Monnier|first2=J. D.|last3=Tuthill|first3=P. G.|last4=Cohen|first4=R. W.|last5=De Buizer|first5=J. M.|last6=Packham|first6=C.|last7=Ciardi|first7=D.|last8=Hayward|first8=T.|last9=Lloyd|first9=J. P.|year=2007|doi=10.1086/517993|s2cid=16694}}</ref>

<ref name=aaa474_2_653>{{Cite journal| first1=F. | last1=van Leeuwen |date=November 2007 | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 |arxiv = 0708.1752| s2cid=18759600 }}</ref>

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}}

==Further reading==
* {{cite encyclopedia|url=http://www.daviddarling.info/encyclopedia/M/Mira.html|title=Mira (Omicron Ceti)|encyclopedia=The Encyclopedia of Astrobiology, Astronomy, and Spaceflight |access-date=June 22, 2006}}
* Robert Burnham Jr., ''Burnham's Celestial Handbook'', Vol. 1, (New York: Dover Publications, Inc., 1978), 634.
* James Kaler, ''The Hundred Greatest Stars'', (New York: Copernicus Books, 2002), 121.

==External links==
{{Commons}}
* [http://www.nasa.gov/mission_pages/galex/galex-20070815.html Speeding Bullet Star Leaves Enormous Streak Across Sky] at [[Caltech]]
* [http://news.bbc.co.uk/1/hi/sci/tech/6947607.stm Mira has tail nearly 13 light years in length (BBC)]
* [[Astronomy Picture of the Day]]:<br />[http://antwrp.gsfc.nasa.gov/apod/ap981011.html 1998-10-11], [http://antwrp.gsfc.nasa.gov/apod/ap010121.html 2001-01-21], [http://antwrp.gsfc.nasa.gov/apod/ap060722.html 2006-07-22], [http://antwrp.gsfc.nasa.gov/apod/ap070221.html 2007-02-21], [http://antwrp.gsfc.nasa.gov/apod/ap070817.html 2007-08-17]
* [http://spider.seds.org/spider/Vars/mira.html SEDS article]
* A [http://www.bav-astro.de/sterne/cetmira.shtml lightcurve] of Mira from the BAV.
* Universe Today, [http://www.universetoday.com/2007/08/15/thats-not-a-comet-thats-a-star/ That's Not a Comet, that's a Star]
* [https://www.aavso.org/vsots_mira OMICRON CETI (Mira)]
* [https://www.aavso.org/vsots_mira2 Winter 2006: Mira revisited]

{{Stars of Cetus}}
{{Portal bar|Astronomy|Stars|Outer space}}
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[[Category:Bayer objects|Ceti, Omicron]]
[[Category:Binary stars]]
[[Category:Cetus]]
[[Category:Mira variables]]
[[Category:M-type giants]]
[[Category:Stars with proper names]]
[[Category:Flamsteed objects|Ceti, 68]]
[[Category:Hipparcos objects|010826]]
[[Category:Bright Star Catalogue objects|0681]]
[[Category:Henry Draper Catalogue objects|014386]]
[[Category:Emission-line stars]]
[[Category:Durchmusterung objects]]