View source for B612 Foundation

{{Short description|Planetary defense nonprofit organization}}
{{Use mdy dates|date=September 2025}}
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{{Infobox organization
| name                = B612 Foundation
| logo                = B612 Foundation logo.png
| logo_size           = 200px
| vector_logo         = 
| type                = [[501(c) organization|501(c)(3) not-for-profit organization]]
| tax_id              = 54-2078469
| registration_id     = C2467899
| formation           = October 7, 2002<ref name="B612 Foundation History" />
| founder             = Dr. [[Clark Chapman]]<br>Dr. [[Piet Hut]]<br>Dr. [[Ed Lu]]<br>[[Rusty Schweickart]]
| location_city       = [[Mill Valley, California]]
| location_country    = USA
| origins             = 
| key_people          = Dr. [[Marc W. Buie|Marc Buie]], SMS<br>[[B612 Foundation#Tom Gavin, Chair, Review Team|Tom Gavin]], SSRT<br>Dr. [[G. Scott Hubbard|Scott Hubbard]], SPA<br>Dr. [[David Liddle]], BoD<br>Dr. [[Ed Lu]], Director, Asteroid Institute,<br>Diane Murphy, PR<br>Dr. [[Harold Reitsema]], SMD<br>Danica Remy, CEO<br>[[B612 Foundation#John Troeltzsch, Sentinel Program Manager|John Troeltzsch]], SPM
| revenue             = 
| purpose             = [[Asteroid impact avoidance|Planetary defense]]
| products            = [[Asteroid Institute]]
| homepage            = [https://b612foundation.org/ B612 Foundation]
| footnotes           = 
}}

The '''B612 Foundation''' is a private [[Nonprofit organization|nonprofit]] [[Private foundation (United States)|foundation]] headquartered in [[Mill Valley, California]], United States, dedicated to planetary science and [[Asteroid impact avoidance|planetary defense]] against [[asteroid]]s and other  [[Impact event|near-Earth object (NEO) impacts]]. It is led mainly by scientists, former astronauts and engineers from the [[Institute for Advanced Study]], [[Southwest Research Institute]], [[Stanford University]], [[NASA]] and the [[space industry]].

As a [[non-governmental organization]] it has conducted two lines of related research to help detect NEOs that could one day strike the [[Earth]], and find the technological means to divert their path to avoid such collisions. It also assisted the [[Association of Space Explorers]] in helping the [[United Nations]] establish the [[United Nations Committee on the Peaceful Uses of Outer Space#Near-Earth object deflection and disaster response|International Asteroid Warning Network]], as well as a  Space Missions Planning Advisory Group to provide oversight on proposed [[Asteroid impact avoidance#Collision avoidance strategies|asteroid deflection]] missions.

In 2012, the foundation announced it would design and build a privately financed asteroid-finding [[space observatory]], the [[Sentinel Space Telescope]], to be launched in 2017–2018. Once stationed in a [[heliocentric orbit]] around the Sun similar to that of [[Venus]], Sentinel's supercooled [[infrared detector]] would have helped identify dangerous asteroids and other NEOs that pose a risk of collision with Earth. In the absence of substantive planetary defense provided by governments worldwide, B612 attempted a fundraising campaign to cover the Sentinel Mission, estimated at $450 million for 10 years of operation. Fundraising was unsuccessful, and the program was cancelled in 2017, with the Foundation pursuing a constellation of smaller satellites instead.<ref>{{Cite web|url=http://spacenews.com/b612-studying-smallsat-missions-to-search-for-near-earth-objects/|title = B612 studying smallsat missions to search for near Earth objects|date = June 20, 2017}}</ref>

The B612 Foundation is named for the asteroid home of the [[eponym]]ous hero of [[Antoine de Saint-Exupéry]]'s 1943 book ''[[The Little Prince]]''.

== Background ==
{{main|Impact events|Asteroid impact avoidance}}
When an [[asteroid]] enters the planet's atmosphere it becomes known as a '[[meteor]]'; those that survive and fall to the Earth's surface are then called '[[meteorite]]s'. While basketball-sized meteors occur almost daily, and compact car-sized ones about yearly, they usually burn up or explode high above the Earth as [[bolide]]s, (fireballs), often with little notice.  During an average 24-hour period, the Earth sweeps through some 100 million particles of interplanetary dust and pieces of cosmic debris, only a very minor amount of which arrives on the ground as meteorites.<ref name="USA Today-2013.10.06" />

[[File:Meteor Crater (crop-tight).jpg|thumb|left|The 1,200 meter-wide [[Meteor Crater]] in [[Arizona]], United States, created by a 46 meter-diameter asteroid impact. A visitors centre is visible beyond the far rim.]]

The larger in size asteroids or other [[near-Earth object]]s (NEOs) are, the less frequently they impact the planet's atmosphere—large meteors seen in the skies are extremely rare, while medium-sized ones are less so, and much smaller ones are more commonplace. Although stony asteroids often explode high in the atmosphere, some objects, especially [[iron meteorite|iron-nickel meteors]] and other types descending at a steep angle,<ref name="Atlantic-2008.06.01" /> can explode close to ground level or even directly impact onto land or sea. In the U.S. [[Arizona|State of Arizona]], the {{Convert|1200|m|ft|adj=mid|-wide}} [[Meteor Crater]] (officially named Barringer Crater) formed in a fraction of a second as nearly 160 million tonnes of limestone and bedrock were uplifted, creating its crater rim on formerly flat terrain. The asteroid that produced the Barringer Crater was only about {{convert|46|m}} in size; however it impacted the ground at a velocity of {{cvt|12.8|km/s|mph}} and struck with an impact energy of {{convert|10|MtTNT}}—about 625 times greater than the [[Little Boy|bomb that destroyed the city of Hiroshima]] during World War II.<ref name="Melosh, Collins" /><ref name="Schaber" /> [[Tsunami]]s can also occur after a medium-sized or larger asteroid impacts an ocean surface or other large body of water.<ref name="Paine" />

[[Image:Toutatis.jpg|thumb|right|A radar image of the almost 2 km wide [[4179 Toutatis|Asteroid 4179 Toutatis]], one of many objects that [[potentially hazardous asteroid|could pose a severe catastrophic threat]]]]

The probability of a mid-sized asteroid (similar to the one that [[Tunguska event|destroyed the Tunguska River area of Russia in 1908]]) hitting Earth during the 21st century has been estimated at 30%.<ref>Hernandez, Vittorio. [http://www.ibtimes.com.au/former-nasa-astronaut-predicts-30-chance-near-earth-asteroid-hit-within-century-1306747 Former NASA Astronaut Predicts 30% Chance of Near-Earth Asteroid Hit Within Century] {{Webarchive|url=https://web.archive.org/web/20200728152808/https://www.ibtimes.com.au/former-nasa-astronaut-predicts-30-chance-near-earth-asteroid-hit-within-century-1306747 |date=July 28, 2020 }}, ''[[International Business Times]]'', March 21, 2013.</ref>  Since the Earth is currently more populated than in previous eras, there is a greater risk of large casualties arising from a mid-sized asteroid impact.<ref name="Ashbury Park Press-2013.03.27" />  However, as of the early 2010s, only about a half of one per cent of Tunguska-type NEOs had been located by astronomers using ground-based telescope surveys.<ref name="New York Times-2013.11.06" />

The need for an asteroid detection program has been compared to the need for monsoon, typhoon, and hurricane preparedness.<ref name="USA Today-2013.10.06" /><ref name="Wired-2014.04" /> As the B612 Foundation and other organizations have publicly noted, of the different types of [[Disaster|natural catastrophes]] that can occur on our planet, asteroid strikes are the only one that the world now has the technical capability to prevent.

B612 is one of several organizations to propose detailed dynamic surveys of NEOs and preventative measures such as asteroid deflection.<ref name="Discover-2013.10" /><ref name="Economist-2013.07.03" /> Other groups include Chinese researchers, [[NASA]] in the United States, [[NEOShield]] in Europe, as well as the international [[The Spaceguard Foundation|Spaceguard Foundation]].  In December 2009 [[Russian Federal Space Agency|Roscosmos Russian Federal Space Agency]] director [[Anatoly Perminov]] proposed a deflection mission to the {{convert|325|m|ft|adj=mid|-wide}} asteroid [[99942 Apophis]], which at the time had been thought to pose a risk of collision with Earth.<ref name="New York Times-2009.12.30" /><ref name="World Post-2009.12.30" />

=== Asteroid deflection workshop ===
The Foundation evolved from an informal one-day workshop on [[Asteroid impact avoidance#Collision avoidance strategies|asteroid deflection]] strategies during October 2001, organized by Dutch [[Astrophysics|astrophysicist]] [[Piet Hut]] along with physicist and then-U.S. astronaut [[Ed Lu]], presented at [[NASA Johnson Space Center|NASA's Johnson Space Center]] in Houston, Texas.  Twenty researchers participated, principally from various NASA facilities plus the non-profit [[Southwest Research Institute]], but as well from the University of California, University of Michigan, and the Institute for Independent Study. All were interested in contributing to the proposed creation of an asteroid deflection capability.<ref name="B612-Foundation History-2004.03.22" /> The seminar participants included [[Rusty Schweickart]], a former [[List of Apollo astronauts|Apollo astronaut]], and [[Clark Chapman]], a [[Planetary science|planetary scientist]].<ref name="B612 Foundation History" /><ref name="Universe Today-2005.06.07" />

Among the proposed experimental research missions discussed were the alteration of an asteroid's spin rate, as well as changing the orbit of one part of a binary asteroid pair.<ref name="B612 Foundation History" /><ref name="Universe Today-2005.06.07" /> Following the seminar's round-table discussions the workshop generally agreed that the vehicle of choice (needed to deflect an asteroid) would be powered by a low-thrust ion plasma engine. Landing a nuclear-powered [[Plasma propulsion engine|plasma engined]] pusher vehicle on the asteroid's surface was seen as promising, an early proposal that would later encounter a number of technical obstacles.<ref name="NPR-2005.11.10" />  Nuclear explosives were seen as "too risky and unpredictable" for several reasons,<ref name="NPR-2005.11.10" /> warranting the view that gently altering an asteroid's trajectory was the safest approach—but also a method requiring years of advance warning to successfully accomplish.<ref name="B612-Foundation History-2004.03.22" /><ref name="Universe Today-2005.06.07" />

== B612 Project and Foundation ==
The October 2001 asteroid deflection workshop participants created the "B612 Project" to further their research. Schweickart, along with Drs. Hut, Lu and Chapman, then formed the B612 Foundation on October 7, 2002,<ref name="B612 Foundation History" /><ref name="Universe Today-2005.06.07" /> with its first goal being to "significantly alter the orbit of an asteroid in a controlled manner".<ref name="Institute for Advanced Study-Piet Hut" /> Schweickart became an early public face of the foundation and served as chairman on its [[board of directors]].<ref name="Universe Today-2010.10.14" /> In 2010, as part of an ''ad hoc'' task force on planetary defense, he advocated increasing NASA's annual budget by $250M–$300 million over a 10-year period (with an operational maintenance budget of up to $75 million per year after that) in order to more fully catalog the [[near-Earth object]]s (NEOs) that can pose a threat to Earth, and to also fully develop impact avoidance capabilities.  That recommended level of budgetary support would permit up to 10–20 years of advance warning in order to create a sufficient window for the required trajectory deflection.<ref name="NASA-Task Force Planetary Defense-2010.10.06" /><ref name="New York Times-2010.10.25" />

Their recommendations were made to a NASA Advisory Council, but were ultimately unsuccessful in obtaining Congressional funding due to NASA, lacking a legislated mandate for [[Asteroid impact avoidance|planetary protection]],<ref name="Atlantic-2008.06.01" /><ref name="Popular Mechanics-2006.12" /> not being permitted to request it.<ref name="Discover-2013.09" /><ref name="National Geographic-2004.03.08" /><ref name="Scientific American-2013.10.28" /> Feeling it would be imprudent to continue waiting for substantive government or United Nations action,<ref name="RIA Novosti-2014.08.14" /><ref name="NPR-2013.11.03" /> B612 began a fundraising campaign in 2012 to cover the approximate US$450 million cost for the development, launch and operations of an asteroid-finding [[Space observatory|space telescope]],<ref name="Discovery.com-2013.10.28" /><ref name="B612-Media Release-2012.09.19" /> to be called [[Sentinel Space Telescope|Sentinel]], with a goal of raising $30 to $40 million per year.<ref name="Aviation Week-2013.04.09" /> The [[space observatory]]'s objective would be to accurately survey NEOs from an orbit similar to that Venus, creating a large dynamic catalog of such objects that would help identify dangerous Earth-impactors, deemed a necessary precursor to mounting any asteroid deflection mission.

[[File:2013 Senate testimony Ed Lu.webm|thumb|"Assessing the Risks, Impacts and Solutions for Space Threats"; testimony before a U.S. Senate Subcommittee on Science & Space, March 2013<ref name="SpacePolicyOnline.com-2013.04.04" /> (video)]]

In March and April 2013, several weeks after the [[Chelyabinsk meteor]] explosion injured some 1,500 people, the [[United States Congress|U.S. Congress]] held hearings for "...the Risks, Impacts and Solutions for Space Threats". They received testimony from B612 head Ed Lu (see video at right), as well as Dr. Donald K. Yeomans, head of NASA's NEO Program Office, Dr. [[Michael A'Hearn]] of the University of Maryland and co-chair of a 2009 U.S. National Research Council study on asteroid  threats, plus others.<ref name="SpacePolicyOnline.com-2013.04.04" /> The difficulty of quickly intercepting an imminent asteroid threat to Earth was made apparent during the testimony:

{{blockquote|REP. STEWART: ... are we technologically capable of launching something that could intercept [an asteroid with 2 years of advance warning]? ... <br>DR. A'HEARN: No. If we had spacecraft plans on the books already, that would take a year—I mean a typical small mission ... takes four years from approval to start to launch ... | author=[[Chris Stewart (politician)|Rep. Chris Stewart (R–UT)]] and Dr. Michael F. A'Hearn, April 10, 2013 | source=United States Congress<ref name="US Congress-2013.04.10" />}}

As a result of a set of hearings by the NASA Advisory Committee following the Chelyabinsk explosion in 2013, in conjunction with a White House request to double its budget, NASA's Near Earth Object Program funding was increased to $40.5 M/year in its FY2014 (Fiscal Year 2014) budget.  It had previously been increased to $20.5 M/year in FY2012 (about 0.1% of NASA's annual budget at the time),<ref name="Discover-2013.09" /> from an average of about $4 M/year between 2002 and 2010.<ref name="NASA HQ-NEOOP-2014.02.28" />

=== Asteroid hazard reassessment ===
On [[Earth Day]], April 22, 2014, the B612 Foundation formally presented a revised assessment on the frequency of "city-killer" type impact events, based on research led by Canadian planetary scientist Peter Brown of the [[University of Western Ontario]]'s (UWO) [[CPSX|Centre for Planetary Science and Exploration]].<ref name="Christian Science Monitor-2014.04.23" /> Dr. Brown's analysis, "A 500-Kiloton Airburst Over Chelyabinsk and An Enhanced Hazard from Small Impactors", published in the journals [[Science (journal)|Science]] and [[Nature (journal)|Nature]],<ref name="New York Times-2013.11.06" /><ref name="Nature-2013.11.06" /> was used to produce a short computer-animated video that was presented to the media at the [[Museum of Flight|Seattle Museum of Flight]].<ref name="Aviation Week-2014.04.23" /><ref name="B612-Impact video media release 2014.04.17" />

The nearly one and a half minute video displayed a rotating globe with the impact points of about 25 asteroids measuring more than one, and up to 600 kilotons of blast force, that struck the Earth from 2000 to 2013 (for comparison, the [[Little Boy|nuclear bomb that destroyed Hiroshima]] was equivalent to about [[TNT equivalent|16 kilotons of TNT]] blast force).<ref name="Christian Science Monitor-2014.04.23" /><ref name="B612-impact video" /> Of those impacts between 2000 and 2013, eight of them were as large, or larger, than the Hiroshima bomb.<ref name="Wired-2014.04" /> Only one of the asteroids, [[2008 TC3|2008 TC<sub>3</sub>]], was [[Asteroid impact prediction|detected in advance]], some 19 hours before exploding in the atmosphere. As was the case with the [[Chelyabinsk meteor|2013 Chelyabinsk meteor]], no warnings were issued for any of the other impacts.<ref name="BBC News-2014.04.22" />{{#tag:ref|

[[2008 TC3|2008 TC<sub>3</sub>]], an 80-tonne,  4.1-meter (13 ft)  diameter asteroid,<ref name="Nature-2009.Iss.7237" /> entered Earth's atmosphere on October 7, 2008,<ref name="Discover Magazine-2008.10.06" /> and exploded over the [[Nubian Desert]] in [[Sudan]].  It was the first time an asteroid impact had been predicted prior to its entry into the atmosphere as a meteor, and its discovery and impact prediction were considered a "remarkable feat" considering its small four meter size.<ref name="Roylance2008" /> The asteroid was identified about 19 hours before impact by [[Richard A. Kowalski|Richard Kowalski]] of the [[Catalina Sky Survey]] near Tucson, Arizona, in the United States.<ref name="Williams-2008" /><ref name="jplneo" /> Although officials in the U.S. Government were advised of the impending impact, no warning was provided to the Sudanese Government. According to Donald Yeomans, head of NASA's Near Earth Objects Program at the [[Jet Propulsion Laboratory]], "NASA alerted the White House, the National Security Council, the Pentagon, the State Department, and the Department of Homeland Security... But no one from the United States alerted Sudan because the two countries did not have diplomatic relations".<ref name="Christian Science Monitor-2013.02.16">Spotts, Pete. [https://www.csmonitor.com/Science/2013/0216/Russian-asteroid-highlights-astronomers-challenge-predicting-such-space-objects Russian Asteroid Highlights Astronomers' Challenge: Predicting Such Space Objects] {{Webarchive|url=https://web.archive.org/web/20200728175010/https://www.csmonitor.com/Science/2013/0216/Russian-asteroid-highlights-astronomers-challenge-predicting-such-space-objects |date=July 28, 2020 }}, ''[[The Christian Science Monitor]]'', February 16, 2013. Retrieved August 27, 2014.</ref>

|group="Note"|}}

At the presentation, alongside former NASA astronauts [[B612 Foundation#Tom Jones, Strategic Adviser|Dr. Tom Jones]] and [[Apollo 8]] astronaut [[William Anders|Bill Anders]],<ref name="Aviation Week-2014.04.23" /><ref name="B612-Impact video media release 2014.04.17" /> Foundation head [[Ed Lu]] explained that the frequency of dangerous [[impact event|asteroid impacts]] hitting Earth was from three to ten times greater than previously believed a dozen or so years ago (earlier estimates had pegged the odds as one per 300,000 years).<ref name="Atlantic-2008.06.01" />  The latest reassessment is based on worldwide [[infrasound]] signatures recorded under the auspices of the [[Comprehensive Nuclear-Test-Ban Treaty Organization]], which monitors the planet for nuclear explosions.  Dr.  Brown's UWO study used infrasound signals generated by asteroids that released more than a kiloton of TNT explosive force. The study suggested that "city-killer" type impact events similar to the [[Tunguska event]] of 1908 actually occur on average about once a century instead of every thousand years, as was once previously believed. The 1908 event occurred in the remote, sparsely populated [[Podkamennaya Tunguska River|Tunguska area]] of [[Siberia]], Russia, and is attributed to the likely airburst explosion of an asteroid or comet that destroyed some 30 million trees over 2,150 square kilometres (830 sq mi) of forests.<ref>{{Cite book|title=The Tunguska Mystery|date=2009|publisher=Springer|isbn=978-0-387-76573-0|author-last=Rubtsov|author-first=Vladimir}}</ref>  The higher frequency of these types of events is interpreted as meaning that "blind luck" has mainly prevented a catastrophic impact over an inhabited area that could kill millions, a point made near the video's end.<ref name="Christian Science Monitor-2014.04.23" /><ref name="Aviation Week-2014.04.23" /><ref name="B612-impact video" /><ref name="NBC Nightly News-2014.04.22" />

=== 99942 Apophis ===
During the first decade of the 2000s, there were serious concerns the 325 metres (1,066&nbsp;ft) wide asteroid [[99942 Apophis]] posed a risk of impacting Earth in 2036. Preliminary, incomplete data by astronomers using ground-based sky surveys resulted in the calculation of a Level 4 risk on the [[Torino Scale|Torino Scale impact hazard chart]]. In July 2005, B612 formally asked NASA to investigate the possibility that the asteroid's post-2029 orbit could be in [[orbital resonance]] with Earth, which would increase the likelihood of a future impact. The Foundation also asked NASA to investigate whether a [[transponder]] should be placed on the asteroid to enable more accurate tracking of how its orbit would be changed by the [[Yarkovsky effect]].<ref name="Morrison-2005" />

By 2008, B612 had provided estimates on a 30 kilometers-wide corridor, called a "path of risk", that would extend across the Earth's surface if an impact were to occur, as part of its effort to develop viable [[Asteroid deflection strategies|deflection strategies]].<ref name="Schweickart et al-2006" /> The calculated risk-path extended from [[Kazakhstan]] across southern Russia through Siberia, across the Pacific, then right between [[Nicaragua]] and [[Costa Rica]], crossing northern [[Colombia]] and [[Venezuela]], and ending in the Atlantic just before reaching Africa.<ref name="Gennery-2007" /> At that time, a computer simulation estimated Apophis's hypothetical impact in countries, such as Colombia and Venezuela, could have resulted in more than 10 million casualties.<ref name="Baileya-2006" /> Alternately, an impact in the Atlantic or Pacific oceans could produce a deadly [[tsunami]] over 240 metres (about 800&nbsp;ft) in height, capable of destroying many coastal areas and cities.<ref name="Popular Mechanics-2006.12" />

A series of later, more accurate observations of 99942 Apophis, combined with the recovery of previously unseen data, revised the odds of a collision in 2036 as being virtually nil, and effectively ruled it out.<ref name="Farnocchia" />

=== International involvement ===
B612 Foundation members assisted the [[Association of Space Explorers]] (ASE) in helping obtain United Nations (UN) oversight of NEO tracking and deflection missions through the UN's [[United Nations Committee on the Peaceful Uses of Outer Space|Committee On the Peaceful Uses of Outer Space]] (UN COPUOS) along with COPUOS's Action Team 14 (AT-14) expert group. Several members of B612, also members of the ASE, worked with COPUOS since 2001 to establish international involvement for both impact disaster responses, and on deflection missions to prevent impact events.<ref name="Earth & Sky-2013.10.28" /> According to Foundation ''Chair Emeritus'' Rusty Schweickart in 2013, "No government in the world today has explicitly assigned the responsibility for planetary protection to any of its agencies".<ref name="Discovery.com-2013.10.28" />

In October 2013, COPUOS's Scientific and Technical Subcommittee approved several measures,<ref name="NPR-2013.11.03" /><ref name="Atlantic-2014.08.09" /> later approved by the UN General Assembly in December,<ref name="ESA-2014.08.10" /> to deal with terrestrial asteroid impacts, including the creation of an International Asteroid Warning Network (IAWN) plus two advisory groups: the Space Missions Planning Advisory Group (SMPAG), and the Impact Disaster Planning Advisory Group (IDPAG).<ref name="UNOOSA-press-2013.02.20" /><ref name="Air & Space-2013.02.21" /> The IAWN warning network will act as a clearinghouse for shared information on dangerous asteroids and for any future terrestrial impact events that are identified. The Space Missions Planning Advisory Group will coordinate joint studies of the technologies for deflection missions,<ref name="Telegraph-2013.10.30" /> and as well provide oversight of actual missions. This is due to deflection missions typically involving a progressive movement of an asteroid's predicted impact point across the surface of the Earth (and also across the territories of uninvolved countries) until the NEO is deflected either ahead of, or behind the planet at the point their orbits intersect.<ref name="NPR-2013.11.03" /><ref name="New Scientist-2013.10.28" /> An initial framework of international cooperation at the UN is needed, said Schweickart, to guide the policymakers of its member nations on several important NEO-related aspects. However, as asserted by the Foundation, the new UN measures only constitute a starting point. To be effective they will need to be enhanced by further policies and resources implemented at both the national and supernational levels.<ref name="New York Times-2013.11.06" /><ref name="LA Times-2013.10.28" />

At the time of the UN's policy adoption in New York City, Schweickart and four other ASE members, including B612 head [[Ed Lu]] and strategic advisers [[Dumitru Prunariu]] and [[Thomas David Jones|Tom Jones]] participated in a public forum moderated by [[Neil deGrasse Tyson]] not far from the [[Headquarters of the United Nations|United Nations Headquarters]]. The panel urged the global community to adopt further important steps for planetary defense against NEO impacts. Their recommendations included:<ref name="Earth & Sky-2013.10.28" /><ref name="LA Times-2013.10.28" /><ref name="NBC News-2013.10.25" />
* UN delegates briefing their home countries' policymakers on the UN's newest roles;
* having each country's government create detailed asteroid disaster response plans, assigning fiscal resources to deal with asteroid impacts, and delegating a lead agency to handle its disaster response in order to create clear lines of communication from the IAWN to the affected countries;
* having their governments support the ASE's and B612's efforts to identify the estimated one million "city-killer" NEOs capable of impacting Earth,<ref name="Discovery.com-2013.10.28" /> by deploying a [[Space observatory|space-based asteroid telescope]], and
* committing member states to launching an international test deflection mission within 10 years.

== Sentinel Mission ==
{{Main|Sentinel Space Telescope}}
[[File:Sentinel Space Telescope illustration.jpg|thumb|A depiction of the [[Sentinel (space telescope)|Sentinel Space Telescope]], planned to be built by [[Ball Aerospace & Technologies|Ball Aerospace]]]]
The [[Sentinel (space telescope)|Sentinel Mission]] program was the cornerstone of the B612 Foundation's earlier efforts, with its [[preliminary design review|preliminary design]] and [[Systems architecture|system architecture level]] reviews planned for 2014,<ref name="Aviation Week-2013.04.09" /><ref name="Aviation Week-2014.04.23" /> and its [[Design review (U.S. government)|critical design review]] to be conducted in 2015.<ref name="Aviation Week-2013.04.09" /> The [[infrared telescope]] would be launched atop a [[SpaceX]] [[Falcon 9]] rocket, to be placed into a [[Venus]]-trailing [[heliocentric orbit]] around the Sun. Orbiting between the Sun and Earth, the Sun's rays would always be behind the telescope's lens and thus never inhibit the [[space observatory]]'s ability to detect asteroids or other [[near-Earth object]]s (NEOs).<ref name="Atlantic-2008.06.01" /><ref name="B612-Impact video" /> From the vantage of its inner-solar system orbit around the Sun, Sentinel would be able to "pick up objects that are currently difficult, if not impossible, to see in advance from Earth",<ref name="Aviation Week-2013.04.09" /> such as occurred with the [[Chelyabinsk meteor]] of 2013 that went undetected until its explosion over [[Chelyabinsk Oblast]], [[Russia]].<ref name="New York Times-2013.03.20" /> The Sentinel Mission was planned to provide an accurate dynamic catalog of asteroids and other NEOs made available to scientists worldwide from the [[International Astronomical Union]]'s [[Minor Planet Center]], the data collected would calculate the risk of [[impact events]] with our planet, allowing for asteroid deflection by the use of [[gravity tractor]]s to divert their trajectories away from Earth.<ref name="Discover-2013.10" /><ref name="B612-2002" />

In order to communicate with the spacecraft while it is orbiting the Sun (at about the same distance as Venus), which can be at times as far as 270 million kilometres (170 million miles) from Earth, the B612 Foundation entered into a [[Space Act Agreement]] with NASA for the use of their [[Deep Space Network|deep space telecommunication network]].<ref name="Aviation Week-2014.04.23" />

=== Design and operation ===
Sentinel was designed to perform continuous observation and analysis during its planned {{frac|6|1|2}}-year operational life,<ref name="B612 Factsheet-2" /> although B612 anticipates it may continue to function for up to 10 years.  Using its {{convert|51|cm|adj=on}} telescope mirror with sensors built by [[Ball Aerospace & Technologies|Ball Aerospace]] (makers of the [[Hubble Space Telescope]]'s instruments),<ref name="New York Times-2013.02.16" /> its mission would be to catalog 90% of asteroids with diameters larger than {{convert|140|m}}. There were also plans to catalog smaller Solar System objects as well.<ref name="Discover-2013.09" /><ref name="B612-Sentinel Mission" />

The [[space observatory]] would measure {{convert|7.7|m}} by {{convert|3.2|m}} with a mass of {{convert|1500|kg}} and would orbit the Sun at a distance of {{convert|0.6|to|0.8|AU}} approximately the same orbital distance as [[Venus (planet)|Venus]], employing [[infrared astronomy]] to identify asteroids against the [[Space environment|cold]] of outer space. Sentinel would scan in the 7- to 15-micron [[wavelength]] band across a 5.5 by 2-degree field of view. Its sensor array would consist of 16 detectors with coverage scanning "a 200-degree, full-angle field of regard".<ref name="Aviation Week-2013.04.09" /> B612, working in partnership with Ball Aerospace, was constructing Sentinel's 51&nbsp;cm aluminum mirror, designed for a large field of view with its infrared sensors cooled to {{convert|40|K|C|lk=on}} using Ball's two-stage, [[Stirling-cycle|closed-Stirling-cycle]] [[cryocooler]].<ref name="Ball Aerospace-2013" />

B612 aimed to produce its space telescope at a significantly lower cost than traditional space science programs by making use of space hardware systems previously developed for earlier programs, rather than designing a brand new observatory. Schweickart stated that about  "80% of what we're dealing with in Sentinel is [[Kepler (spacecraft)|Kepler]], 15% [[Spitzer Space Telescope|Spitzer]], 5% new, higher-performance [[Thermographic camera|infrared sensors]]", thus concentrating its R&D funds on the critical area of cryogenically-cooled image sensor technology, producing what it terms will be the most sensitive type of asteroid-finding telescope ever built.<ref name="Discover-2013.09" />

Data gathered by Sentinel would be provided through existing scientific data-sharing networks that include [[NASA]] and academic institutions such as the [[Minor Planet Center]] in [[Cambridge, Massachusetts]]. Given the satellite's telescopic accuracy, Sentinel's data may have proven valuable for other possible future missions, such as [[asteroid mining]].<ref name="New York Times-2013.02.16" /><ref name="B612-Sentinel Mission" /><ref name="Space.com-2012.07.10" />

=== Mission funding ===
B612 was attempting to raise approximately $450M to fund the development, launch and operational costs of the telescope,<ref name="Aviation Week-2013.04.09" /> about the cost of a complex [[Controlled-access highway|freeway]] [[Stack interchange#Five-level stack|interchange]], or approximately $100M less than a single Air Force [[Next-Generation Bomber]].<ref name="California-2014.06" /> The $450 million cost estimate is composed of $250 million to create Sentinel, plus another $200 million for 10 years of operations.<ref name="New York Times-2013.11.06" /> In explaining the Foundation's bypassing of possible governmental grants for such a mission,<ref name="New York Times-2013.03.20" /> Dr. Lu stated their public fundraising appeal is being driven by "[t]he tragedy of the commons: When it's everybody's problem, it's nobody's problem", referring to a lack of ownership, priority and funding that governments have assigned to asteroid threats,<ref name="Atlantic-2008.06.01" /> also stating on a different occasion "We're the only ones taking it seriously."<ref name="California-2014.06" /> According to another B612 board member, Rusty Schweickart,  "The good news is, you can prevent it—not just get ready for it! The bad news is, it's hard to get anybody to pay attention to it when there are potholes in the road."<ref name="New York Times-2011.03.13" /> After providing earlier Congressional testimony on the issue Schweickart was dismayed to hear from congressional staff members that, while [[United States congressional hearing|U.S. lawmakers involved in the hearing]] understood the seriousness of the threat, they would likely not legislate funding for planetary defense as "making the deflection of asteroids a priority might backfire in [their] reelection campaigns".<ref name="New York Times-2008.06.30" />

The Foundation intended to launch Sentinel in 2017–2018,<ref name="B612-Impact video" /><ref name="Scientific American-2013.10" /><ref name="Miami Herald-2014.06.15" /> with initiation of data transfer for on-[[Earth]] processing anticipated no later than 6 months afterwards.<!-- <ref name="B612 Factsheet" />  [ed. note: document no longer available -Z]  -->

In the aftermath of the February 2013 [[Chelyabinsk meteor|Chelyabinsk meteor explosion]]—where an approximate {{convert|20|m}} asteroid entered the atmosphere undetected at about [[Mach number|Mach 60]], becoming a brilliant [[superbolide]] [[meteor]] before exploding over Chelyabinsk, Russia<ref name="New York Times-2013.03.20" /><ref name="NASA-2013.02.15" />—the B612 foundation experienced a "surge of interest" in its project to detect asteroids, with a corresponding increase in funding donations.<ref name="Denver Business Journal-2013.04.09" /> After providing Congressional testimony Dr. Lu noted that the many online videos recorded of the asteroid's explosion over Chelyabinsk made a significant impact on millions of viewers worldwide, saying "There's nothing like a hundred YouTube videos to do that."<ref name="New York Times-2013.03.25" />

== Staff ==

=== Leadership ===
In 2014 eight key staff positions were designated, covering the offices of the [[chief executive officer]] (CEO), [[chief operating officer]] (COO), Sentinel Program Architecture (SPA), Sentinel Mission Direction (SMD), Sentinel Program Management (SPM), Sentinel Mission Science (SMS) and the Sentinel Standing Review Team (SSRT), plus Public Relations.<ref name="B612-Leadership" />

==== Ed Lu, Co-founder, B612 Foundation. Executive Director, Asteroid Institute ====
{{Main|Ed Lu}}
[[File:Ed Lu.jpg|thumb|175px|Ed Lu, co-founder and executive director, Asteroid Institute a B612 program]]
Edward Tsang "Ed" Lu ({{zh|c=盧傑|p=Lú Jié}}; born July 1, 1963) is a co-founder and the chief executive officer of the B612 Foundation, and as well, a U.S. [[physicist]] and a former [[NASA Astronaut Corps|NASA astronaut]]. He is a veteran of two [[Space Shuttle program|Space Shuttle missions]] and an extended stay aboard the [[International Space Station]] which included a six-hour spacewalk outside the station performing construction work.  During his three missions he logged a total of 206 days in space.<ref name="NASA-bio Ed Lu" />

His education includes an electrical engineering degree from [[Cornell University]], and a Ph.D. in applied physics from [[Stanford University]]. Lu became a specialist in [[solar physics]] and [[astrophysics]] as a visiting scientist at the [[High Altitude Observatory]] based in Boulder, Colorado, from 1989 until 1992. In his final year, he held a joint appointment with the [[Joint Institute for Laboratory Astrophysics]] at the [[University of Colorado]].  Lu performed postdoctoral fellow work at the [[Institute for Astronomy (Hawaii)|Institute for Astronomy]] in [[Honolulu, Hawaii]] from 1992 until 1995 before being selected for NASA's Astronaut Corps in 1994.<ref name="NASA-bio Ed Lu" />

Lu developed a number of new theoretical advances, which have provided for the first time a basic understanding of the underlying physics of [[solar flare]]s. Besides his work on solar flares he has published journal articles and scientific papers on a wide range of topics including [[cosmology]], [[solar oscillation]]s, [[statistical mechanics]], [[plasma physics]], [[Near-Earth object#Near-Earth asteroids|near-Earth asteroids]],<ref name="NASA-bio Ed Lu" />  and is also a co-inventor of the [[Gravity tractor|gravitational tractor]] concept of [[Asteroid impact avoidance#Collision avoidance strategies|asteroid deflection]].<ref name="B612-2002" /><ref name="Nature-Vol. 438 No. 7065-Lu, Love" />

In 2007 Lu retired from NASA to become the Program Manager on [[Google]]'s [[Project Ara|Advanced Projects Team]],<ref name="NASA-Press Release: 07-176" /> and also worked with [[Liquid Robotics]] as its Chief of Innovative Applications, and at Hover Inc. as its [[chief technology officer]].<ref name="Silicon Valley News-2012.06.06" /> While still at NASA during 2002 Lu co-founded the B612 Foundation, later serving as its Chair and in 2014 is currently its [[chief executive officer]].<ref name="NASA-bio Ed Lu" /><ref name="B612-bio Ed Lu" />

Lu holds a [[commercial pilot license]] with multi-engine instrument ratings, accumulating some 1,500 hours of flight time. Among his honors are NASA's highest awards, its [[NASA Distinguished Service Medal|Distinguished Service]] and [[NASA Exceptional Service Medal|Exceptional Service medals]], as well as the Russian Gagarin, Komorov and [[Georgy Beregovoy|Beregovoy Medals]].<ref name="NASA-bio Ed Lu" />

==== Tom Gavin, Chairman, Sentinel Standing Review Team ====
[[File:Thomas R. Gavin at NASA's Jet Propulsion Laboratory.jpg|175px|thumb|Tom Gavin, Chair, Sentinel Standing Review Team (SSRT)]]
Thomas R. Gavin is the chairman of the B612 Foundation's Sentinel Standing Review Team (SSRT), and a former executive-level manager at [[NASA]].  He served with NASA for 30 years, including his position as Associate Director for Flight Programs and Mission Assurance at their [[Jet Propulsion Laboratory]] (JPL) organization, and "has been at the forefront in leading many of the most successful U.S. space missions, including Galileo's mission to Jupiter, [[Cassini–Huygens|Cassini–Huygens mission to Saturn]], development of Genesis, [[Stardust (spacecraft)|Stardust]], [[2001 Mars Odyssey|Mars 2001 Odyssey]], [[Mars rover|Mars Exploration Rovers]], [[Spitzer Space Telescope|SPITZER]] and [[GALEX|Galaxy Evolution Explorer]] programs."<ref name="ASK Magazine-2004.04.01" />

In 2001 he was appointed associate director for flight projects and mission success for NASA's Jet Propulsion Laboratory in May 2001. This was a new position created to provide the JPL Director's Office with oversight of flight projects. He later served as interim director for Solar System exploration. Previously, he was director of JPL's Space Science Flight Projects Directorate, which oversaw the Genesis, Mars 2001 Odyssey, Mars rovers, Spitzer Space Telescope and GALEX projects. He also served as deputy director of JPL's Space and Earth Science Programs Directorate beginning in December 1997. In June 1990 he was appointed spacecraft system manager for the Cassini–Huygens mission to Saturn, and retained that position until the project's successful launch in 1997. From 1968 to 1990 he was a member of the Galileo and Voyager project offices responsible for mission assurance.<ref name="NASA-Jet Propulsion Laboratory: Thomas R. Gavin" /> He received his bachelor's degree in chemistry from [[Villanova University]] in Pennsylvania in 1961.<ref name="NASA-Jet Propulsion Laboratory: Thomas R. Gavin" />

Gavin has been honored on a number of occasions for exceptional work, receiving NASA's Distinguished and Exceptional Service Medals in 1981 for his work on the [[Voyager program|Voyager space probes program]], [[NASA Outstanding Leadership Medal|NASA's Medal for Outstanding Leadership]] in 1991 for Galileo, and again in 1999 for the Cassini-Hygens mission. In 1997 ''[[Aviation Week and Space Technology]]'' presented its Laurels Award to him for outstanding achievement in the field of space. He also earned the [[American Astronomical Society]]'s 2005 [[William Randolph Lovelace II|Randolph Lovelace II Award]] for his management of all [[Jet Propulsion Laboratory]] and NASA robotic science spacecraft missions.<ref name="NASA-Gavin" /><ref name="B612-bio Tom Gavin" />

==== Scott Hubbard, Sentinel Program Architect ====
{{Main|G. Scott Hubbard}}
[[File:73331main hubbarm.jpg|thumb|175px|Dr. Scott Hubbard, Sentinel Program Architect]]
Dr. G. Scott Hubbard is the B612 Foundation's Sentinel Program Architect, as well as a physicist, academic and a former executive-level manager at [[NASA]], the U.S. space agency. He is a professor of Aeronautics and Astronautics at [[Stanford University]] and has been engaged in space-related research as well as program, project and executive management for more than 35 years including 20 years with [[NASA]], culminating his career there as director of NASA's [[Ames Research Center]]. At Ames he was responsible for overseeing the work of some 2,600 scientists, engineers and other staff.<ref name="NASA-bio G. Scott Hubbard" /> Currently on the [[SpaceX]] Safety Advisory Panel,<ref name="SocCaltech.com-2012.03.29" /> he previously served as NASA's sole representative on the [[Columbia Accident Investigation Board|Space Shuttle Columbia Accident Investigation Board]], and also as their first [[Mars Exploration Program]] director in 2000, successfully restructuring the entire Mars program in the wake of earlier serious mission failures.<ref name="NASA-bio G. Scott Hubbard" /><ref name="San Francisco Chronicle-2012.02.29" />

Hubbard founded [[NASA Astrobiology Institute|NASA's Astrobiology Institute]] in 1998; conceived the [[Mars Pathfinder]] mission with its airbag landing system and was the manager for their highly successful [[Lunar Prospector|Lunar Prospector Mission]]. Prior to joining NASA, Hubbard led a small start-up high technology company in the San Francisco Bay Area and was a staff scientist at the [[Lawrence Berkeley National Laboratory]]. Hubbard has received many honors including NASA's highest award, their [[NASA Distinguished Service Medal|Distinguished Service Medal]], and the  [[American Institute of Aeronautics and Astronautics]]'s [[Theodore von Karman Medal|Von Karman Medal]].<ref name="NASA-bio G. Scott Hubbard" /><ref name="Stanford-bio G. Scott Hubbard" />

Hubbard was elected to the [[International Academy of Astronautics]], is a Fellow of the American Institute of Aeronautics and Astronautics, has authored more than 50 scientific papers on research and technology and also holds the [[Carl Sagan|Carl Sagan Chair]] at the [[SETI Institute]].<ref name="NASA-bio G. Scott Hubbard" /> His education includes an undergraduate degree in physics and astronomy at [[Vanderbilt University]] and a graduate degree in solid state and semiconductor physics at the [[University of California at Berkeley]].<ref name="NASA-bio G. Scott Hubbard" />

==== Marc Buie, Sentinel Mission Scientist ====
{{Main|Marc W. Buie}}
[[File:Marc Buie headshot (cropped).jpg|thumb|175px|Dr. Marc Buie, Sentinel Mission Scientist]]
Dr. Marc W. Buie (b. 1958) is the foundation's Sentinel Mission Scientist, and as well a U.S. [[astronomer]] at [[Lowell Observatory]] in [[Flagstaff, Arizona]]. Buie received his B.Sc. in physics from [[Louisiana State University]] in 1980 and earned his Ph.D. in Planetary Science from the [[University of Arizona]] in 1984. He was a post-doctoral fellow at the [[University of Hawaii]] from 1985 to 1988. From 1988 to 1991, he worked at the [[Space Telescope Science Institute]] where he assisted in the planning of the first planetary observations made by the [[Hubble Space Telescope]].

Since 1983, [[Pluto]] and its moons have been a central theme of the research done by Buie, who has published over 85 scientific papers and journal articles.<ref name="SwRI-biblio Marc W. Buie" />  He is also one of the co-discoverers of Pluto's new moons, [[Nix (moon)|Nix]] and [[Hydra (moon)|Hydra]] (Pluto II and Pluto III) discovered in 2005.

Buie has worked with the [[Deep Ecliptic Survey]] team who have been responsible for the discovery of over a thousand such distant objects. He also studies the [[Kuiper Belt]] and transitional objects such as [[Chiron|2060 Chiron]] and [[5145 Pholus]], as well as the occasional comets as with the recent [[Deep impact mission]] that travelled to [[Comet Tempel 1]], and near-Earth asteroids with the occasional use of the Hubble and [[Spitzer Space Telescope]]s. Buie also assists in the development of advanced astronomical instrumentation.

[[7553 Buie|Asteroid 7553 Buie]] is named in honor of the astronomer, who has also been profiled as part of an article on Pluto in ''[[Air & Space/Smithsonian|Air & Space Smithsonian]]'' magazine.<ref name="Air & Space Smithsonian-1996.June–July" />

==== Harold Reitsema, Sentinel Mission Director ====
{{Main|Harold Reitsema}}
[[File:Dr. Harold Reitsema (cropped).jpg|thumb|175px|Dr. Harold Reitsema, Sentinel Mission Director]]
Dr. Harold James Reitsema (b. January 19, 1948, Kalamazoo, Michigan) is the foundation's Sentinel Mission Director and a U.S. [[astronomer]]. Reitsema was formerly Director of Science Mission Development at [[Ball Aerospace & Technologies]], the B612 Foundation's prime contractor for designing and building its [[space telescope|space telescope observatory]].<ref name="Denver Business Journal-2012.07.06" /> In his early career during the 1980s he was part of the teams that discovered new moons orbiting Neptune and Saturn through ground-based telescopic observations.<ref name="SEDS-Larissa" /> Using a [[Coronagraph|coronagraphic imaging]] system with one of the first [[charge-coupled device]]s available for astronomical use, they first observed [[Telesto (moon)|Telesto]] in April 1980, just two months after being one of the first groups to observe [[Janus (moon)|Janus]], also a moon of Saturn. Reitsema, as part of a different team of astronomers, observed [[Larissa (moon)|Larissa]] in May 1981, by watching the occultation of a star by the Neptune system. Reitsema is also responsible for several advances in the use of [[false-color]] techniques applied to astronomical images.<ref name="NASA-Colorful Comets" />

Reitsema was a member of the Halley Multicolour Camera team on the [[European Space Agency]] [[Giotto mission|Giotto]] spacecraft that took close-up images of [[Comet Halley]] in 1986. He has been involved in many of NASA's space science missions including the [[Spitzer Space Telescope]], [[Submillimeter Wave Astronomy Satellite]], the [[New Horizons]] mission to Pluto and the [[Kepler Space Observatory]] project searching for Earth-like planets orbiting distant stars similar to the Sun.

Reitsema participated in the ground-based observations of [[Deep Impact (spacecraft)|Deep Impact]] mission in 2005, observing the impact of the spacecraft on the [[Tempel 1]] comet using the telescopes of the [[Sierra de San Pedro Mártir|Sierra de San Pedro Mártir Observatory]] in Mexico, along with colleagues from the [[University of Maryland, College Park|University of Maryland]] and the Mexican [[National Astronomical Observatory (Mexico)|National Astronomical Observatory]].<ref name="American Astronomical Society Bulletin-2005.12" />

Reitsema retired from Ball Aerospace in 2008 and remains a consultant to NASA and the aerospace industry in mission design and [[Near-Earth Objects]]. His education includes his B.A. in physics from [[Calvin College]] in [[Grand Rapids, Michigan]] in 1972 and a Ph.D. in astronomy from [[New Mexico State University]] in 1977.  [[Asteroid belt|Main-belt]]  [[13327 Reitsema|Asteroid 13327 Reitsema]] is named after him to honor his achievements.

==== John Troeltzsch, Sentinel Program Manager ====
John Troeltzsch is the B612 Foundation's Sentinel Program Manager, a senior U.S. [[Aerospace engineering|aerospace engineer]] and as well a program manager with [[Ball Aerospace & Technologies]].  Ball Aerospace is the Sentinel's prime contractor responsible for its design and integration, to be later launched aboard a [[SpaceX]] [[Falcon 9]] rocket into a Venus-trailing [[heliocentric orbit]] around the Sun. Troeltzsch's responsibilities include overseeing all requirements for the observatory's detailed design and build at Ball. As part of his 31 years of service with them, he helped create three of the [[Hubble Space Telescope]]'s instruments and also managed the [[Spitzer Space Telescope]] program until its launch in 2003. Troeltzsch later became the [[Kepler (spacecraft)|Kepler Mission]] program manager at Ball in 2007.<ref name="ISETI-Troeltzsch" />

Troeltzsch's program management abilities include experience with [[Aerospace engineering|spacecraft systems engineering]] and [[System integration|software integration]] through all phases of space telescope projects, from contract definition through assembly, launch and on-station operational start up.  His past project experience includes the Kepler Mission, Hubble's [[Goddard High Resolution Spectrograph]] (GHRS) and its [[Corrective Optics Space Telescope Axial Replacement|COSTAR Space Telescope corrective optics]], as well as the cryogenically-cooled instruments on the [[Spitzer Space Telescope]].<ref name="B612-bio John Troeltzsch" />

Troeltzsch was awarded the [[NASA Exceptional Public Service Medal]] for his commitment to the success of the Kepler mission.<ref name="B612-bio John Troeltzsch" /> His education includes a B.Sc. and an M.Sc. in [[Aerospace Engineering]], both from the [[University of Colorado]] in 1983 and 1989 respectively, the latter while employed at Ball Aerospace which hired him immediately after the completion of his undergraduate degree.<ref name="ISETI-Troeltzsch" />

==== David Liddle, Chair, Board of Directors ====
{{Main|David Liddle}}
Dr. David Liddle is the foundation's Board Chair and a former technology industry executive and professor of computer science. He also holds the Chair of many [[Board of directors|boards of directors]], including research institutes, in the United States.

Liddle is a partner at the venture capital firm [[U.S. Venture Partners]], and is a co-founder and former CEO of both the [[Interval Research Corporation]] and [[Metaphor Computer Systems]], plus  a consulting professor of [[computer science]] at [[Stanford University]], credited with heading development of the [[Xerox Star]] computer system. He served as an executive at the [[Xerox Corporation]] and [[IBM]] and currently serves on the board of directors of Inphi Corporation, the ''[[The New York Times|New York Times]]'' and the B612 Foundation.<ref name="Stanford-bio David Liddle" /><ref name="B612-bio David Liddle" /> In January 2012, he also joined the board of directors of [[SRI International]].<ref name="Stanford Research Insitute-2012.01.04" />

Liddle also held the chair of the board of trustees for the [[Santa Fe Institute]], a nonprofit theoretical research center, from 1994 to 1999,<ref name="Santa Fe Institute-1999.Fall" /> and served on the U.S.'s [[DARPA]] Information, Science and Technology Committee.<ref name="Stanford-bio David Liddle" /> Additionally, he was Chair of the [[Board on Science, Technology, and Economic Policy|Computer Science and Telecommunications Board]] of the [[United States National Research Council|U.S. National Research Council]] due to his work on human-computer interface designs. In a field unrelated to the sciences and technology, Liddle is a [[Fellow|Senior Fellow]] of the [[Royal College of Art]] in London, England.<ref name="Stanford-bio David Liddle" />

His education includes a B.Sc. in electrical engineering from the [[University of Michigan]] and a Ph.D. in [[Electrical engineering|Electrical Engineering and Computer Science]] from the [[University of Toledo]].<ref name="Stanford-bio David Liddle" />

=== Board of directors ===
As of 2014 the B612 Foundation's board includes Geoffrey Baehr (formerly with [[Sun Microsystems]] and [[U.S. Venture Partners]]), plus [[Doctorate|Doctors]] Chapman, [[Piet Hut]], [[Ed Lu]] (also CEO, see Leadership, above), David Liddle (Chair, see Leadership, above), and Dan Durda, a planetary scientist.<ref name="B612-TF" /><ref name="B612-Board of Directors" />

==== Rusty Schweickart, co-founder and chair emeritus ====
{{Main|Rusty Schweickart}}

Russell Louis "Rusty" Schweickart (b. October 25, 1935) is a co-founder of the B612 Foundation and chair emeritus of its board of directors.  He is also a former [[List of Apollo astronauts|U.S. Apollo astronaut]], research scientist, Air Force pilot, plus business and government executive. Schweickart, chosen in [[NASA Astronaut Group 3|NASA's third astronaut group]], is best known as the [[Apollo Lunar Module|lunar module]] pilot on the [[Apollo 9]] mission, the spacecraft's first crewed flight test on which he performed the first in-space test of the [[portable life support system]] used by the Apollo astronauts who walked on the Moon. Prior to joining NASA, Schweickart was a scientist at the [[Massachusetts Institute of Technology]]'s  Experimental Astronomy Laboratory, where he researched upper [[atmospheric physics]] and became an expert in [[Spacecraft attitude control|star tracking]] and the stabilization of stellar images, a crucial requirement for space navigation. Schweickart's education includes a B.Sc. in [[Aerospace engineering|aeronautical engineering]] and an M.Sc. in Aeronautics–Astronautics, both from the [[Massachusetts Institute of Technology]] (MIT), in 1956 and 1963 respectively. His Master's thesis was on the validation of "theoretical models of stratospheric radiance".<ref name="NASA-bio Rusty Schweickart" />

After serving as the backup commander of NASA's [[Skylab 2|first crewed Skylab mission]] (the United States' first [[space station]]), he later became director of User Affairs in their Office of Applications. Schweickart left NASA in 1977 to serve for two years as California governor [[Jerry Brown]]'s assistant for science and technology, and was then appointed by Brown to [[California Energy Commission|California's Energy Commission]] for five and a half years.<ref name="NASA-bio Rusty Schweickart" /><ref name="Pacific Sun-2004.07.07" />

Schweickart co-founded the [[Association of Space Explorers]] (ASE) with other astronauts in 1984–85 and chaired the ASE's NEO Committee, producing a benchmark report, ''Asteroid Threats: A Call for Global Response'', and submitting it to the [[United Nations Committee on the Peaceful Uses of Outer Space]] (UN COPUOS). He then co-chaired, along with astronaut Dr. [[Thomas David Jones|Tom Jones]], [[National Advisory Committee for Aeronautics#NASA Advisory Council|NASA's Advisory Council]]'s Task Force on Planetary Defense. In 2002 he co-founded B612, also serving as its chair.<ref Name="McBarton-2010" /><ref name="B612-bio Rusty Schweickart" />

Schweickart is a Fellow of the [[American Astronautical Society]], the [[International Academy of Astronautics]] and the [[California Academy of Sciences]], as well as an associate fellow of the [[American Institute of Aeronautics and Astronautics]]. Among the honors he has received are the [[Federation Aeronautique Internationale]]'s [[De la Vaulx Medal]] in 1970 for his Apollo 9 flight, both of NASA's [[NASA Distinguished Service Medal|Distinguished Service]] and [[NASA Exceptional Service Medal|Exceptional Service medals]], and, unusual for an astronaut, an [[Emmy Award]] from the U.S. [[National Academy of Television Arts and Sciences]] for transmitting the first live TV pictures from space.<ref name="NASA-bio Rusty Schweickart" /><ref name="Pacific Sun-2004.07.07" /><ref name="M.I.T. Alumni" />

==== {{anchor|Clark R. Chapman}} Clark Chapman, co-founder and board member ====
Clark Chapman is a B612 board member and "a planetary scientist whose research has specialized in studies of asteroids and cratering of planetary surfaces, using telescopes, spacecraft, and computers.  He is a past chair of the Division for Planetary Sciences (DPS) of the [[American Astronomical Society]] and was the first editor of the [[Journal of Geophysical Research|''Journal of Geophysical Research: Planets'']].  He is a winner of the [[Carl Sagan Award for Public Understanding of Science]] and has worked on the science teams of the [[MESSENGER]], [[Galileo (spacecraft)|Galileo]] and [[NEAR Shoemaker|Near-Earth Asteroid Rendezvous]] space missions."<ref name="B612-bio Clark Chapman"/>

Chapman has a degree from [[Harvard University]] and has earned two degrees from the [[Massachusetts Institute of Technology]], including his Ph.D., in the fields of [[astronomy]], [[meteorology]] and the [[planetary science]]s, and also served at the [[Planetary Science Institute]] in [[Tucson, Arizona]]. He is currently on faculty at the [[Southwest Research Institute]] of [[Boulder, Colorado]].<ref name="B612-bio Clark Chapman" />

==== {{anchor|Dan Durda}} Dan Durda, board member ====
[[File:Dan Durda.jpg|thumb|175px|Dr. Dan Durda, B612 board member, prior to a [[Neil A. Armstrong Flight Research Center|NASA Dryden]] F-18 astronomy mission]]
Dr. Daniel David "Dan" Durda (b. October 26, 1965, Detroit, Michigan),<ref name="SwRI-bio Dan Durda" /> is a B612 board member and "a principal scientist in the Department of Space Studies of the [[Southwest Research Institute]]'s (SwRI) Boulder Colorado. He has more than 20 years experience researching the collisional and dynamical evolution of main-belt and near-Earth asteroids, Vulcanoids, Kuiper belt comets, and interplanetary dust."<ref name="B612-bio Dan Durda" /> He is the author of 68 journal and scientific articles and has presented his reports and findings at 22 professional symposiums.  He has also taught as adjunct professor in the Department of Sciences at [[Front Range Community College]].<ref name="SwRI-bio Dan Durda" />

Durda is an active instrument-rated pilot who has flown numerous aircraft, including high performance [[F/A-18 Hornet]]s and the [[F-104 Starfighter]]s, and "was a 2004 NASA astronaut selection finalist. Dan is one of three SwRI payload specialists who will fly on multiple suborbital spaceflights on Virgin Galactic's Enterprise and XCOR Aerospace's Lynx."<ref name="B612-bio Dan Durda" />

His education includes a B.Sc. in astronomy from [[The University of Michigan]], plus an M.Sc. and a Ph.D., both in astronomy at the [[University of Florida]], in 1987, 1989 and 1993 respectively.  Besides winning the University of Florida's Kerrick Prize "for outstanding contributions in astronomy", [[6141 Durda|Asteroid 6141 Durda]] is named in his honour.<ref name="SwRI-bio Dan Durda" />

=== Strategic advisers ===
As of July 2014, the Foundation has taken on over twenty key advisers drawn from the sciences, the space industry and other professional fields. Their goals are to provide both advice and critiques, and assist in several other facets of the Sentinel Mission.  Included among them are:<ref name="B612-Strategic Advisors" /> Dr. [[Alexander Galitsky]], a former Soviet computer scientist and B612 Founding Circle adviser;<ref name="Financial Post-2014.06.12" /> British [[Astronomer Royal]], cosmologist and astrophysicist [[Martin Rees, Baron Rees of Ludlow|Lord Martin Rees]], the Baron Rees of Ludlow; U.S. ''[[Star Trek]]'' director [[Alexander Singer]]; U.S. science journalist and writer [[Andrew Chaikin]]; British astrophysicist and songwriter Dr. [[Brian May]]; U.S. astronomer [[Carolyn S. Shoemaker|Carolyn Shoemaker]]; U.S. astrophysicist Dr. [[David Brin]]; Romanian cosmonaut [[Dumitru Prunariu]]; U.S. physicist and mathematician Dr. [[Freeman Dyson]]; U.S. astrophysicist and former [[Harvard-Smithsonian Center for Astrophysics]] head Dr. [[Irwin I. Shapiro|Irwin Shapiro]]; U.S. film director [[Jerry Zucker (film director)|Jerry Zucker]]; British-U.S. balloonist [[Julian Nott (balloonist)|Julian Nott]]; Dutch astrophysicist and B612 co-founder Dr. [[Piet Hut]]; former U.S. ambassador [[Philip Lader]];  British cosmologist and astrophysicist Dr. [[Roger Blandford]]; U.S. writer and [[Whole Earth Catalog]] founder [[Stewart Brand]]; U.S. media head [[Tim O'Reilly]]; and former U.S. NASA astronaut Dr. [[Thomas David Jones|Tom Jones]].

==== Tom Jones, strategic adviser ====
{{Main|Thomas David Jones}}
[[File:Thomas D. Jones NASA portrait 313045main jones-226.jpg|thumb|175px|Dr. Tom Jones, strategic adviser]]
Dr. Thomas David "Tom" Jones (b. January 22, 1955) is a strategic adviser to B612,  member of the [[National Advisory Committee for Aeronautics#NASA Advisory Council|NASA Advisory Council]] and a former U.S. astronaut and planetary scientist who has studied asteroids for [[NASA]], engineered intelligence-gathering systems for the CIA, and helped develop advanced mission concepts to explore the Solar System. In his 11 years with NASA he flew on four [[Space Shuttle]] missions, logging a total of 53 days in space. His flight time included three spacewalks to install the centerpiece science module of the [[International Space Station]] (ISS). His publications include ''Planetology: Unlocking the Secrets of the Solar System.''<ref name="B612-bio Tom Jones" /><ref name="Jones, Stofan-2008" />

After graduating from the [[U.S. Air Force Academy]] where he received his B.Sc. in 1977, Jones earned a Ph.D. in [[Planetary Science]]s from the [[University of Arizona]] in 1988. His research interests included the remote sensing of asteroids, meteorite spectroscopy, and applications of space resources. In 1990 he joined [[Science Applications International Corporation]] in Washington, D.C. as a senior scientist. Dr. Jones performed advanced program planning for NASA's [[Goddard Space Flight Center]]'s Solar System Exploration Division. His work there included the investigation of future [[Mars rover|robotic missions to Mars]], asteroids, and the outer Solar System.<ref name="B612-bio Tom Jones" /><ref name="NASA-bio Tom Jones" />

After a year of training following his selection by NASA he became an astronaut in July 1991. In 1994 he flew as [[mission specialist]]s on successive flights of various [[Space Shuttle]]s, running science operations on the "night shift" during [[STS-59]], successfully deploying and retrieving two science satellites. While helping set a shuttle mission endurance record of nearly 18 days in orbit, Jones used Columbia's robotic [[Canadarm]] to release the [[Wake Shield Facility|Wake Shield]] satellite and later grapple it from orbit. His last space flight was in February 2001, helping to deliver the U.S. [[Destiny Laboratory Module]] to the ISS where he helped install the laboratory module in a series of three space walks lasting over 19 hours.  That installation marked the start of onboard scientific research on the ISS.<ref name="NASA-bio Tom Jones" />

Among his honors are NASA's medals and awards for Space Flight, Exceptional Service and Outstanding Leadership, plus the  [[Federation Aeronautique Internationale]]'s (FAI) [[Vladimir Komarov#Legacy|Komarov Diploma]] and a NASA Graduate Student Research Fellowship.<ref name="NASA-bio Tom Jones" />

==== Piet Hut, co-founder and strategic adviser ====
{{Main|Piet Hut}}
[[File:Piet-Hut-174x200.jpg|thumb|175px|Dr. Piet Hut, B612 Foundation co-founder and strategic adviser]]
Dr. Piet Hut (b. September 26, 1952, Utrecht, The Netherlands) is a co-founder of the B612 Foundation, one of its strategic advisers, and a [[Dutch people|Dutch]] [[Astrophysics|astrophysicist]], who divides his time between research in computer simulations of dense stellar systems and broadly interdisciplinary collaborations, ranging from fields in [[natural science]] to [[computer science]], [[cognitive psychology]] and [[philosophy]].  He is currently Program Head in [[Interdisciplinarity|Interdisciplinary Studies]] at the [[Institute for Advanced Study]] in [[Princeton, New Jersey]],<ref name="Institute for Advanced Study-Faculty" /><ref name="Institute for Advanced Study-Piet" /> former home to [[Albert Einstein]].

Hut's specialization is in "stellar and planetary dynamics; many of his more than two hundred articles are written in collaboration with colleagues from different fields, ranging from particle physics, geophysics and paleontology to computer science, cognitive psychology and philosophy."<ref name="B612-bio Piet Hut" /><ref name="Institute for Advanced Study-2014" />  Dr. Hut was an early adviser to Lu and served as a founding member of the B612 Foundation's board of directors.<ref name="Universe Today-2005.06.07" />

Hut has held positions in a number of faculties, including the Institute for Theoretical Physics, [[Utrecht University]] (1977–1978); the Astronomical Institute at the [[University of Amsterdam]] (1978–1981); Astronomy Department of the [[University of California, Berkeley]] (1984–1985) and in the Institute for Advanced Study, in Princeton, N.J. (1981–present).  He has held honors, functions, fellowships and memberships in almost 150 different professional organizations, universities and conferences, and published over 225 papers and articles in scientific journals and symposiums, including his first in 1976 on "The Two-Body problem with a Decreasing Gravitational Constant".<ref name="Institute for Advanced Study-Piet CV" /> In 2014 he became a strategic adviser to the B612 Foundation.

His education includes an M.Sc. from the University of Utrecht and a double Ph.D. in [[particle physics]] and [[astrophysics]] from the University of Amsterdam in 1977 and 1981 respectively. He is the namesource for [[17031 Piethut|Asteroid 17031 Piethut]] honoring his work in [[Planetary science|planetary dynamics]] and for his co-founding of B612.<ref name="Institute for Advanced Study-2014" />

==== Dumitru Prunariu, strategic adviser ====
{{Main|Dumitru Prunariu}}
[[File:Medvedev and Prunariu (cropped).jpeg|thumb|175px|Dr. Dumitru Prunariu, strategic advisor and former chairman of the [[United Nations Committee on the Peaceful Uses of Outer Space|UN COPUOS]]]]
Dr. Dumitru-Dorin Prunariu ({{IPA|ro|duˈmitru doˈrin pruˈnarju}}, b. September 27, 1952) is a retired [[Romania]]n [[cosmonaut]] and a strategic advisor to the B612 Foundation. In 1981 he flew an eight-day mission to the Soviet [[Salyut 6]] [[space station]] where he and his crewmates completed experiments in [[astrophysics]], [[space radiation]], [[space technology]], and [[space medicine]].  He received the Hero of the Socialist Republic of Romania, the [[Hero of the Soviet Union]], the "Hermann Oberth Gold Medal", the "Golden Star Medal" and the [[Order of Lenin]].

Prunariu is a member of the [[International Academy of Astronautics]], the Romanian National [[Committee on Space Research|COSPAR]] Committee, and the [[Association of Space Explorers]] (ASE). In 1993, until 2004, he was the permanent representative of the ASE at the [[United Nations Committee on the Peaceful Uses of Outer Space]] (UN COPUOS) and has represented Romania at COPUOS sessions since 1992.  He also became the vice-president of the International Institute for Risk, Security and Communication Management (EURISC), and from 1998 to 2004 the president of the [[Romanian Space Agency]]. In 2000 he was appointed Associate Professor on Geopolitics within the Faculty of International Business and Economics, Academy of Economic Studies in Bucharest and in 2004 he was elected COPUOS's Chairman of the Scientific and Technical Subcommittee. He was then elected as COPUOS's top level chairman, serving from 2010 to 2012, and also elected as the president of the ASE with a three-year mandate.

Prunariu has co-authored several books on space flight and both presented and published numerous scientific papers. His education includes a degree in [[aerospace engineering]] in 1976 from the [[Politehnica University of Bucharest]]. His Ph.D. thesis led to improvements in the field of [[Flight dynamics (spacecraft)|space flight dynamics]].

== Deflection methods ==
{{Main|Asteroid impact avoidance#Collision avoidance strategies|l1=Asteroid impact avoidance –Collision avoidance strategies}}
A number of methods have been devised to 'deflect' an asteroid or other NEO away from an Earth-impacting trajectory, so that it can entirely avoid entering the Earth's atmosphere.  Given sufficient advance lead time, a change to the body's velocity of as little as one centimetre per second will allow it to avoid hitting the Earth.<ref name="Scientific American-2003.11" />  Proposed and experimental deflection methods include [[Ion Beam Shepherd|ion beam shepherds]], focused [[solar energy]] and the use of [[mass driver]]s or [[solar sail]]s.

Initiating a [[nuclear explosive]] device above, on, or slightly beneath, the surface of a threatening NEO is a potential deflection option, with the optimal detonation height dependent upon the NEO's composition and size.  In the case of a threatening "rubble pile", the stand off, or detonation height above the surface configuration has been put forth as a means to prevent the potential fracturing of the rubble pile.<ref name="Physics.nist" /><ref name="FlightGlobal-2007.08.03" /> However, given sufficient advance warning of an asteroid's impact, most scientists avoid endorsing explosive deflection due to the number of potential issues involved.<ref name="NPR-2005.11.10" /> Other methods that can accomplish NEO deflections include:

=== Gravity tractor ===
{{main|Gravity tractor}}
An alternative to an explosive deflection is to move a dangerous asteroid slowly and consistently over time. The effect of a tiny constant thrust can accumulate to deviate an object sufficiently from its predicted course. In 2005 Drs. [[Ed Lu]] and [[Stanley G. Love]] proposed using a large, heavy uncrewed spacecraft hovering over an asteroid to gravitationally pull the latter into a non-threatening orbit. The method will function due to the spacecraft's and asteroid's mutually [[Gravitation|gravitational attraction]].<ref name="NPR-2005.11.10" /> When the spacecraft counters the gravitational attraction towards the asteroid by the use of, for example, an [[nuclear electric rocket|ion thruster engine]], the net effect is that the asteroid is accelerated, or moved, towards the spacecraft and thus slowly deflected from the orbital path that will lead it to a collision with Earth.<ref name="BBC News-2012.01.20" />

While slow, this method has the advantage of working irrespective of an asteroid's composition.  It would even be effective on a [[comet]], loose [[rubble pile]], or an object spinning at a high rate.  However, a gravity tractor would likely have to spend several years stationed beside and tugging on the body to be effective. The [[Sentinel Space Telescope]]'s mission is designed to provide the required advance lead time.

According to Rusty Schweickart, the [[gravitational tractor]] method also has a controversial aspect because during the process of changing an asteroid's trajectory, the point on Earth where it would most likely hit would slowly be shifted temporarily across the face of the planet. It means the threat for the entire planet might be minimized at a temporary cost of some specific states' security. Schweickart recognizes that choosing the manner and direction the asteroid should be "dragged" may be a difficult international decision, and one that should be made through the United Nations.<ref name="Wired-2009.12" />

An early [[NASA]] analysis of deflection alternatives in 2007, stated: "'Slow push' mitigation techniques are the most expensive, have the lowest level of technical readiness, and their ability to both travel to and divert a threatening NEO would be limited unless mission durations of many years to decades are possible."<ref name="NASA-Deflection Analysis" /> But a year later in 2008 the B612 Foundation released a technical evaluation of the gravity tractor concept, produced on contract to NASA.  Their report confirmed that a transponder-equipped tractor  "with a simple and robust spacecraft design" can provide the needed towing service for a 140-meters-diameter equivalent, Hayabusa-shaped asteroid or other NEO.<ref name="B612-Gravity Tractor Report" />

=== Kinetic impact ===
{{See also|Deep Impact (spacecraft)|Lightweight Exo-Atmospheric Projectile|AIDA (spacecraft)}}
[[File:PIA07923 modest.jpg|thumb|An artist's rendering of NASA's [[Deep Impact (spacecraft)|Deep Impact]] spacecraft next to [[Tempel 1|Comet Tempel 1]]]]
[[File:Deep Impact HRI.jpeg|thumb|Deep Impact being crashed into Comet Tempel 1 in July 2005 (photographed from a companion spacecraft), an example of a technique that can alter a NEO's trajectory.]]
When the asteroid is still far from Earth, a means of deflecting the asteroid is to directly alter its [[momentum]] by colliding a spacecraft with the asteroid. The further away from the Earth, the smaller the required impact force becomes.  Conversely, the closer a dangerous [[near-Earth Object]] (NEO) is to Earth at the time of its discovery, the greater the force that is required to make it deviate from its collision trajectory with the Earth.  Closer to Earth, the impact of a massive spacecraft is a possible solution to a pending NEO impact.

In 2005, in the wake of the successful U.S. mission that crashed its [[Deep Impact (spacecraft)|Deep Impact]] probe into [[Tempel 1|Comet Tempel 1]], China announced its plan for a more advanced version: the landing of a spacecraft probe on a small NEO in order to push it off course.<ref name="Economic Times-2005.07.07" /> In the 2000s the [[European Space Agency]] (ESA) began studying the design of a space mission named [[Don Quijote (space probe)|Don Quijote]], which, if flown, would have been the first intentional asteroid deflection mission ever designed. ESA's [[Advanced Concepts Team]] also demonstrated theoretically that a deflection of [[99942 Apophis]] could be achieved by sending a spacecraft weighing less than a tonne to impact against the asteroid.

ESA had originally identified two NEOs as possible targets for its Quijote mission: {{mpl|2002 AT|4}} and [[(10302) 1989 ML]].<ref name="ESA.int-Don Quijote" /> Neither asteroid represents a threat to Earth. In a subsequent study, two different possibilities were selected: the [[Amor asteroid]] [[2003 SM84]] and [[99942 Apophis]]; the latter is of particular significance to Earth as it will make a close approach in 2029 and 2036. In 2005, ESA announced at the 44th annual [[Lunar and Planetary Science Conference]] that its mission would be combined into a joint ESA-NASA [[AIDA (spacecraft)|Asteroid Impact & Deflection Assessment]] (AIDA) mission, proposed for 2019–2022. The target selected for AIDA will be a [[binary asteroid]], so that the deflection effect could also be observed from Earth by timing the rotation period of the binary pair.<ref name="BBC News-2012.01.20" /> AIDA's new target, a component of binary asteroid [[65803 Didymos]], will be impacted at a velocity of 22,530&nbsp;km/h (14,000&nbsp;mph)<ref name="ESA.int-AIDA study" /><ref name="ESA.int-NEO.2013.01.15" /><ref name="Huffington Post-2013.03.25" />

A [[NASA]] analysis of deflection alternatives, conducted in 2007, stated: "Non-nuclear kinetic impactors are the [[Deep Impact (spacecraft)|most mature approach]] and could be used in some deflection/mitigation scenarios, especially for NEOs that consist of a single small, solid body."<ref name="NASA-Deflection Analysis" />

== Funding status ==
The B612 Foundation is a California [[501(c)(3)]] non-profit, private foundation. Financial contributions to the B612 Foundation are tax-exempt in the United States.  Its principal offices are in [[Mill Valley, California]];<ref name="B612-TF" /> they were previously located in [[Tiburon, California]].<ref name="Mone" />

Fund raising has not gone well for B612 as of June 2015.  With an overall goal to raise {{USD|450 million}} for the project, the foundation raised only approximately {{USD|1.2 million}} in 2012 and {{USD|1.6 million}} in 2013.<ref name=nature20150619>{{cite news |last1=Watson |first1=Traci |title=Private asteroid hunt lacks cash to spy threats in orbit |url=http://www.nature.com/news/private-asteroid-hunt-lacks-cash-to-spy-threats-in-orbit-1.17810 |access-date=June 20, 2015 |work=Nature |date=June 19, 2015 |quote=Yet progress has been slow. The B612 Foundation raised donations of roughly $1.2 million in 2012 and $1.6 million in 2013 — far short of its annual goal of $30 million to $40 million. NASA says that Sentinel has also missed every development milestone laid out in the 2012 agreement. |archive-date=November 25, 2020 |archive-url=https://web.archive.org/web/20201125032732/http://www.nature.com/news/private-asteroid-hunt-lacks-cash-to-spy-threats-in-orbit-1.17810 |url-status=live }}</ref>{{update inline|date=September 2021}}

== Foundation name ==
{{Main|The Little Prince}}
The B612 Foundation is named in tribute to the [[eponym]]ous home asteroid of the hero of [[Antoine de Saint-Exupéry]]'s best-selling philosophical fable of ''Le Petit Prince'' (''[[The Little Prince]]'').<ref name="NPR-2005.11.10" /><ref name="Institute for Advanced Study-Piet Hut" /><ref name="Discover-2013.09" /><ref name="Pacific Sun-2004.07.07" /> In aviation's early pioneer years of the 1920s, Saint-Exupéry made an emergency landing on top of an African [[mesa]] covered with crushed white limestone seashells.  Walking around in the moonlight he kicked a black rock and soon deduced it was a meteorite that had fallen from space.<ref name="Post Road Magazine-Iss.8" /><ref name="New York Times-2014.06.21" />

That experience later contributed, in 1943, to his literary creation of Asteroid B-612<!-- do not wikilink: now goes to an Australian hard rock band --> in his philosophical fable of a little prince fallen to Earth,<ref name="New York Times-2014.06.21" /> with the home [[Minor planet|planetoid]]'s name having been adapted from one of the mail planes Saint-Exupéry once flew, bearing the registration marking A-612.

Also inspired by the story is an asteroid discovered in 1993, though not identified as posing any threat to Earth, named ''[[46610 Bésixdouze]]'' (the numerical part of its designation represented in [[hexadecimal]] as 'B612', while the textual part is French for "B six twelve"). As well, a small [[Minor-planet moon|asteroid moon]], [[Petit-Prince (moon)|''Petit-Prince'']], discovered in 1998 is named in part after ''The Little Prince''.<ref name="B612-Bésixdouze" /><ref name="William" />

== See also ==
{{div col|colwidth=30em}}
* [[Qingyang event]]
* [[99942 Apophis]]
* [[Asteroid impact prediction]]
* [[Asteroid impact avoidance]]
* [[Asteroid Day]]
* [[Asteroid Terrestrial-impact Last Alert System]] (ATLAS)
* [[Deep Space Industries]]
* [[Gravity tractor]]
* [[List of impact craters on Earth]]
* [[List of meteor air bursts]]
* [[NEOShield]]
* [[Near Earth Object Surveillance Satellite]] (NEOS Sat)
* [[Planetary Resources]]
* [[Potentially hazardous object]]
* [[Spaceguard]]
* [[Spaceguard Foundation]]
* [[Tunguska event]]
* [[United Nations Committee on the Peaceful Uses of Outer Space]] (UN COPUOS)
{{div col end}}

== References ==

{{Include-NASA}}

''' Notes '''

{{reflist|group=Note|colwidth=30em}}

''' Citations '''

{{Reflist|colwidth=30em|refs=

<ref name="Air & Space Smithsonian-1996.June–July">"Pluto's Portrait: Even The Mighty Hubble Has To Strain To See This Tiny, Distant Planet", ''[[Air & Space/Smithsonian|Air & Space Smithsonian magazine]]'', June/July 1996, Iss., p 60.</ref>

<ref name="Air & Space-2013.02.21">[[Thomas David Jones|Jones, Tom]]. [http://www.airspacemag.com/space/what-to-do-in-an-asteroid-emergency-24532893/?no-ist What To Do in an Asteroid Emergency: A U.N. action team gets serious about protecting the planet from space rocks] {{Webarchive|url=https://web.archive.org/web/20200728170231/https://www.airspacemag.com/space/what-to-do-in-an-asteroid-emergency-24532893/?no-ist |date=July 28, 2020 }}, ''[[Air & Space/Smithsonian|Air & Space Smithsonian magazine]]'' website, February 21, 2013. Retrieved August 10, 2014.</ref>

<ref name="American Astronomical Society Bulletin-2005.12">Zauderer, B. A.; Walsh, K. J.; Vázquez, R.; Reitsema, H. [http://adsabs.harvard.edu/abs/2005AAS...207.0422Z Deep Impact observations from San Pedro Martir] {{Webarchive|url=https://web.archive.org/web/20210526041503/https://ui.adsabs.harvard.edu/abs/2005AAS...207.0422Z/abstract |date=May 26, 2021 }}, [[American Astronomical Society]], Meeting 207, #04.22; ''[[Bulletin of the American Astronomical Society]]'', Vol. 37, p.1157, December 2005.</ref>

<ref name="Ashbury Park Press-2013.03.27">Sastrowardoyo, Hartriono B. [https://www.usatoday.com/story/news/nation/2013/03/27/east-coast-meteoroid-strike/2026591/ Scientists: East Coast Meteoroid Strike Unlikely] {{Webarchive|url=https://web.archive.org/web/20200726121157/https://www.usatoday.com/story/news/nation/2013/03/27/east-coast-meteoroid-strike/2026591/ |date=July 26, 2020 }}, New Jersey: ''Ashbury Park Press'', March 27, 2013; with contribution by Ledyard King, Gannett Washington Bureau. Retrieved from USAToday.com website, June 30, 2014.</ref>

<ref name="ASK Magazine-2004.04.01">[https://web.archive.org/web/20140714203642/http://appel.nasa.gov/wp-content/uploads/sites/2/2013/08/interview_issue_17_gavin.pdf ASK Talks With Tom Gavin], NASA: ASK Magazine, Iss. 17, April 1, 2004 (PDF).</ref>

<ref name="Atlantic-2008.06.01">[[Gregg Easterbrook|Easterbrook, Gregg]]. [https://www.theatlantic.com/magazine/archive/2008/06/the-sky-is-falling/306807/?single_page=true The Sky Is Falling] {{Webarchive|url=https://web.archive.org/web/20201111164546/https://www.theatlantic.com/magazine/archive/2008/06/the-sky-is-falling/306807/?single_page=true |date=November 11, 2020 }}, ''[[The Atlantic]]'', June 1, 2008. Retrieved September 14, 2014.</ref>

<ref name="Atlantic-2014.08.09">Gilsinan, Kathy. [https://www.theatlantic.com/international/archive/2014/08/asteroid-defense-us-russia-ukraine/375799/ The Enemy of an Asteroid Is My Friend: Taking the Long View on U.S.-Russia Planetary Defense] {{Webarchive|url=https://web.archive.org/web/20201111164925/https://www.theatlantic.com/international/archive/2014/08/asteroid-defense-us-russia-ukraine/375799/ |date=November 11, 2020 }}, ''[[The Atlantic]]'', August 9, 2014.</ref>

<ref name="Aviation Week-2013.04.09">{{cite news | last = Norris | first = Guy | title = Ball Aerospace Ramps Up Sentinel Asteroid Search Mission | url = http://www.aviationweek.com/Article.aspx?id=%2Farticle-xml%2Fawx_04_09_2013_p0-567048.xml#.UWWTzfMZyVI | date = April 9, 2013 | access-date = April 11, 2013 | newspaper = [[Aviation Week & Space Technology]] | archive-date = May 20, 2013 | archive-url = https://web.archive.org/web/20130520184106/http://www.aviationweek.com/Article.aspx?id=%2Farticle-xml%2Fawx_04_09_2013_p0-567048.xml#.UWWTzfMZyVI | url-status = live }}</ref>

<ref name="Aviation Week-2014.04.23">Carreau, Mark. [http://aviationweek.com/space/silicon-valley-nonprofit-amplifies-warnings-asteroid-hazard Silicon Valley Nonprofit Amplifies Warnings Of Asteroid Hazard] {{Webarchive|url=https://web.archive.org/web/20140714114747/http://aviationweek.com/space/silicon-valley-nonprofit-amplifies-warnings-asteroid-hazard |date=July 14, 2014 }}, ''[[Aviation Week & Space Technology|Aviation Week Intelligence Network]]'' website, April 23, 2014.  Retrieved July 1, 2014.</ref>

<ref name="B612-2002">
  {{cite web
 |title=PROJECT B612: Deflecting an Asteroid using Nuclear-Powered Plasma Drive Propulsion (home page)
 |publisher=Project B612 (now B612 Foundation)
 |date=November 26, 2002
 |url=http://b612.boulder.swri.edu/
 |access-date=April 15, 2012
 |url-status=dead
 |archive-url=https://web.archive.org/web/20110712085255/http://b612.boulder.swri.edu/
 |archive-date=July 12, 2011
}}</ref>

<ref name="B612-Bésixdouze">Schmadel, Lutz D. ''Dictionary of Minor Planet Names'', p. 895.</ref>

<ref name="B612-bio Clark Chapman">[http://sentinelmission.org/our-team/board-of-directors/#/clark-chapman Our Team | Clark Chapman] {{webarchive|url=https://web.archive.org/web/20140701070259/http://sentinelmission.org/our-team/board-of-directors/ |date=July 1, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved June 30, 2014.</ref>

<ref name="B612-bio Dan Durda">[http://sentinelmission.org/portfolio/dan-durda/ Our Team | Cark Chapman] {{webarchive|url=https://web.archive.org/web/20140714210529/http://sentinelmission.org/portfolio/dan-durda/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved July 7, 2014.</ref>

<ref name="B612-bio Tom Gavin">[http://sentinelmission.org/portfolio/tom-gavin/ Our Team | Tom Gavin] {{webarchive|url=https://web.archive.org/web/20140714184707/http://sentinelmission.org/portfolio/tom-gavin/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.</ref>

<ref name="B612-bio Piet Hut">[http://sentinelmission.org/our-team/strategic-advisors/#/piet-hut Our Team | Piet Hut] {{webarchive|url=https://web.archive.org/web/20140701070310/http://sentinelmission.org/our-team/strategic-advisors/ |date=July 1, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.</ref>

<ref name="B612-bio David Liddle">[http://sentinelmission.org/portfolio/david-liddle/ Our Team | David Liddle] {{webarchive|url=https://web.archive.org/web/20140714183757/http://sentinelmission.org/portfolio/david-liddle/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved June 30, 2014.</ref>

<ref name="B612-bio Ed Lu">[http://sentinelmission.org/portfolio/ed-lu/ Our Team | Ed Lu, CEO and Co-Founder] {{webarchive|url=https://web.archive.org/web/20140714115049/http://sentinelmission.org/portfolio/ed-lu/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved June 29, 2014.</ref>

<ref name="B612-Gravity Tractor Report">[http://sentinelmission.org/archives/jpl-evaluation-gravity-tractor/ JPL Evaluation of Gravity Tractor: Summary Statement] {{webarchive|url=https://archive.today/20140727031126/http://sentinelmission.org/archives/jpl-evaluation-gravity-tractor/ |date=July 27, 2014 }}by  B612 Foundation regarding its contract with JPL to conduct a detailed performance analysis of a transponder equipped Gravity Tractor spacecraft, September 24, 2008.</ref>

<ref name="B612-bio Rusty Schweickart">[http://sentinelmission.org/portfolio/rusty-schweickart/ Our Team | Rusty Schweickart, Chair Emeritus] {{webarchive|url=https://web.archive.org/web/20140714183755/http://sentinelmission.org/portfolio/rusty-schweickart/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved June 29, 2014.</ref>

<ref name="B612-bio Tom Jones">[http://sentinelmission.org/our-team/#/tom-jones Our Team | Tom Jones] {{Webarchive|url=https://web.archive.org/web/20210308050006/https://sentinelmission.org/our-team/#/tom-jones |date=March 8, 2021 }}, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.</ref>

<ref name="B612-bio John Troeltzsch">[http://sentinelmission.org/our-team/leadership/#/john-troeltzsch Our Team | John Troeltzsch] {{webarchive|url=https://web.archive.org/web/20140714175956/http://sentinelmission.org/our-team/leadership/ |date=July 14, 2014 }}, B612 Foundation, SentinelMission.org website. Retrieved July 15, 2014.</ref>

<ref name="B612-Board of Directors">[http://sentinelmission.org/our-team/board-of-directors/ Board of Directors] {{webarchive|url=https://web.archive.org/web/20140701070259/http://sentinelmission.org/our-team/board-of-directors/ |date=July 1, 2014 }}, B612 Foundation website. Retrieved July 12, 2014.</ref>

<ref name="B612-impact video">[http://sentinelmission.org/list-of-impacts-from-impact-video/ B612 Impact Video] {{webarchive|url=https://web.archive.org/web/20140714141150/http://sentinelmission.org/list-of-impacts-from-impact-video/ |date=July 14, 2014 }}, B612 Foundation.</ref>

<ref name="B612 Foundation History">
  {{cite web|title=Foundation History |publisher=B612 Foundation |url=http://b612foundation.org/b612/foundation-history/ |access-date=April 15, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120229230712/http://b612foundation.org/b612/foundation-history/ |archive-date=February 29, 2012 }}</ref>

<ref name="B612-Foundation History-2004.03.22">[https://web.archive.org/web/20040322172509/http://www.b612foundation.org/about/history.html B612 History], B612 Foundation, March 22, 2004. Retrieved from Archive.org, July 22, 2014.</ref>

<!--  [Rem: document appears to have removed -Z]
<ref name="B612 Factsheet">
  {{cite web
 | title=Sentinel Factsheet
 | publisher= B612 Foundation
 | url=http://b612foundation.org/images/SAA_redacted.pdf
 | format=PDF
 | access-date=September 13, 2012}}</ref>  -->

<ref name="B612 Factsheet-2">
  {{cite web
 |title       = Sentinel Factsheet
 |publisher   = B612 Foundation
 |url         = http://sentinelmission.org/wp-content/uploads/2013/02/D2071_Sentinel-DataSt_313_4-2013.pdf
 |date        = February 2013
 |access-date  = July 11, 2014
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20140714141148/http://sentinelmission.org/wp-content/uploads/2013/02/D2071_Sentinel-DataSt_313_4-2013.pdf
 |archive-date = July 14, 2014
}}</ref>

<ref name="B612-Impact video">
  {{cite web
 |title=B612 Foundation Releases Video at Seattle Museum of Flight Earth Day Event Showing Evidence of 26 Multi-Kiloton Asteroid Impacts Since 2001
 |url=https://b612foundation.org/wp-content/uploads/2014/04/B612_PR_042214.pdf
 |date=April 22, 2014
 |work=B612 Foundation
 |access-date=April 23, 2014
}}{{dead link|date=October 2016 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

<ref name="B612-Impact video media release 2014.04.17">[http://sentinelmission.org/events/b612-earth-day-press-conference-at-the-seattle-museum-of-flight/ Seattle Museum Of Flight To Host Astronauts On Earth Day For Special Program On Protecting Earth From Dangerous Asteroids] {{Webarchive|url=https://web.archive.org/web/20140714144953/http://sentinelmission.org/events/b612-earth-day-press-conference-at-the-seattle-museum-of-flight/ |date=July 14, 2014 }} (media release), B612 Foundation website, April 17, 2014.  Retrieved July 7, 2014.</ref>

<ref name="B612-Leadership">[http://sentinelmission.org/our-team/leadership/ Sentinel Mission Leadership] {{webarchive|url=https://web.archive.org/web/20140714175956/http://sentinelmission.org/our-team/leadership/ |date=July 14, 2014 }}, B612 Foundation website. Retrieved July 11, 2014.</ref>

<ref name="B612-Media Release-2012.09.19">[http://sentinelmission.org/newsroom/press-releases/b612-foundation-receives-new-funding/ B612 Foundation Receives New Funding and Strategic Support From Prominent Leaders in Business, Entertainment, Science and Technology] {{Webarchive|url=https://web.archive.org/web/20140714161127/http://sentinelmission.org/newsroom/press-releases/b612-foundation-receives-new-funding/ |date=July 14, 2014 }}, B612 Foundation, September 19, 2012. Retrieved July 11, 2014.</ref>

<ref name="B612-Sentinel Mission">
  {{cite web
 |title=The Sentinel Mission
 |publisher=B612 Foundation
 |url=http://b612foundation.org/media/sentinelmission/
 |access-date=September 19, 2012
 |url-status=dead
 |archive-url=https://web.archive.org/web/20120910234035/http://b612foundation.org/media/sentinelmission/
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<ref name="Wired-2009.12">Madrigal, Alexis.  [https://www.wired.com/wiredscience/2009/12/saving-earth-from-an-asteroid/ Saving Earth From an Asteroid Will Take Diplomats, Not Heroes] {{Webarchive|url=https://web.archive.org/web/20140301121641/http://www.wired.com/wiredscience/2009/12/saving-earth-from-an-asteroid |date=March 1, 2014 }}, ''[[Wired (magazine)|Wired]]'', December 17, 2009.</ref>

<ref name="Wired-2014.04">Lufkini, Bryan. [http://www.summarizedreading.com/2014/05/the-asteroid-stalker-ed-lu-wants-to.html The Asteroid Stalker] {{Webarchive|url=https://web.archive.org/web/20140714183012/http://www.summarizedreading.com/2014/05/the-asteroid-stalker-ed-lu-wants-to.html |date=July 14, 2014 }} (summarized web article version), ''[[Wired (magazine)|Wired]]'', April 2014, p. 37; and [https://www.wired.com/2014/04/astroid-ed-lu/ This Ex-Astronaut Is Stalking Asteroids to Save Civilization] {{Webarchive|url=https://web.archive.org/web/20161222231205/https://www.wired.com/2014/04/astroid-ed-lu/ |date=December 22, 2016 }}, ''Wired'', April 2014, p. 38. Retrieved June 30, 2014, and July 8, 2014, respectively.</ref>

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}}

== Further reading ==
* Lewis, John S. [https://books.google.com/books?id=0xMZITJqidcC ''Comet And Asteroid Impact Hazards On A Populated Earth: Computer Modeling, Volume 1''], [[Academic Press]], 2000, {{ISBN|0124467601}}, {{ISBN|978-0124467606}}
* Powell, Corey S. [http://discovermagazine.com/2013/oct/16-how-to-dodge-a-cosmic-bullet "How to Deflect a Killer Asteroid: Researchers Come Up With Contingency Plans That Could Help Our Planet Dodge A Cosmic Bullet"], ''[[Discover (magazine)|Discover]]'', September 18, 2013, pp.&nbsp;58–60 (subscription).
* Schweickart, Lu, Hut and Chapman. [https://web.archive.org/web/20050910233139/http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=000EB755-511C-1F7F-911C83414B7F0000 "The Asteroid Tugboat: To Prevent An Asteroid From Hitting Earth, A Space Tug Equipped With Plasma Engines Could Give It A Push"], October 13, 2003, ''[[Scientific American]]''
* Steel, Duncan. [https://books.google.com/books?id=AoA1DhZSJXoC ''Rogue Asteroids and Doomsday Comets: The Search for the Million Megaton Menace That Threatens Life on Earth''], Wiley & Sons, 1995, [1997], {{ISBN|0471193380}}, {{ISBN|978-0-4711-9338-8}}.

== External links ==
* {{Official website}}
* [https://web.archive.org/web/20130210081542/http://b612foundation.org/ B612 Foundation: early website homepage] (archived)
* [https://web.archive.org/web/20140714141148/http://sentinelmission.org/wp-content/uploads/2013/02/D2071_Sentinel-DataSt_313_4-2013.pdf B612 Foundation: Sentinel Mission Factsheet (Feb. 2013, PDF)]
* [https://web.archive.org/web/20140714143037/http://sentinelmission.org/portfolio/changing-the-course-of-the-solar-system-dr-ed-lu-at-tedxmarin/?id=232 Dr. Ed Lu at TEDxMarin: Changing the Course of the Solar System] (video, 14:04)
* [http://www.nbcnews.com/nightly-news/early-warning-telescope-could-detect-dangerous-asteroids-n87191 ''NBC Nightly News'': Early-Warning Telescope Could Detect Dangerous Asteroids], broadcast April 22, 2014 (video, 2:27)
* [https://www.youtube.com/watch?v=Hi54HYX9pWc#t=395 Defending Earth from Asteroids with Neil deGrasse Tyson], public presentation and moderated panel discussion with members of the [[Association of Space Explorers]] and the B612 Foundation, at the [[American Museum of Natural History]], New York City, October 25, 2013 (video, 58:03)
* [http://www.oosa.unvienna.org/pdf/pres/stsc2013/2013neo-02E.pdf NEO Threat Detection and Warning: Plans for an International Asteroid Warning Network], Presentation to the [[United Nations Committee on the Peaceful Uses of Outer Space]] (UN COPUOS) by Dr. Timothy Spahr, Director, [[Minor Planet Center]], [[Smithsonian Astrophysical Observatory]], February 18, 2013 (PDF)
* [https://web.archive.org/web/20140725202348/http://sentinelmission.org/portfolio/ed-lu-congressional-testimony/?id=232 Dr. Ed Lu Congressional Testimony], Washington, D.C., March 20, 2013, [[United States House Science Subcommittee on Space|United States Senate Sub-Committee on Science and Space]]:  "Assessing the Risks, Impacts and Solutions for Space Threats" (video, 23:49)
* {{cite web |url= https://www.pbs.org/wgbh/nova/video/asteroid-doomsday-or-payday/ |title= Asteroid: Doomsday or Payday? |date= November 20, 2013 |publisher= PBS |work= Nova |quote= Includes interviews with B612 Foundation staff }} (DVD, video, 53:24). Also viewable (within some countries) as {{youTube|id=7n5ajSiMwPM |title= Asteroid: Doomsday or Payday?}}
* [https://web.archive.org/web/20141013030023/http://sentinelmission.org/events/rustys-talk-dinosaur-syndrome-avoidance-project-how-gozit/ Rusty's Talk: Dinosaur Syndrome Avoidance Project - How Gozit?], a July 17, 2014, presentation before an audience at NASA's [[Ames Research Center]]'s Director's Colloquium, addressing the status of the three essential elements to avoiding catastrophic asteroid impacts (video, 55:34)

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