|Founded||October 7, 2002|
|Founder(s)||Dr. Clark Chapman
Dr. Piet Hut
Dr. Ed Lu
|Headquarters||Menlo Park, California, United States|
|Key people||Dr. Marc Buie, SMS
Tom Gavin, SSRT
Dr. Scott Hubbard, SPA
Dr. David Liddle, BoD
Dr. Ed Lu, CEO
Dr. Harold Reitsema, SMD
Danica Remy, COO
John Troeltzsch, SPM
Diane Williams Murphy, PR
|Products||Sentinel space telescope|
The B612 Foundation is a private nonprofit foundation with headquarters in the United States, dedicated to planetary defense against asteroid and other 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 Earth, and find the technological means to divert their path to avoid such collisions. In 2012 the foundation announced it would design and build a privately financed asteroid-finding space telescope, Sentinel, to be launched in 2017–2018. Once stationed in an orbit around the sun similar to that of Venus, Sentinel's supercooled infrared telescope will then help identify dangerous asteroids and other NEOs that pose a risk of collision with Earth.
- 1 Background
- 2 B612 Project and Foundation
- 3 Sentinel Mission
- 4 Staff
- 4.1 Leadership
- 4.1.1 Ed Lu, co-founder and CEO
- 4.1.2 Tom Gavin, Chair, Sentinel Standing Review Team
- 4.1.3 Scott Hubbard, Sentinel Program Architect
- 4.1.4 Marc Buie, Sentinel Mission Scientist
- 4.1.5 Harold Reitsema, Sentinel Mission Director
- 4.1.6 John Troeltzsch, Sentinel Program Manager
- 4.1.7 David Liddle, Chair, Board of Directors
- 4.2 Board of Directors
- 4.3 Strategic advisers
- 4.1 Leadership
- 5 Deflection methods
- 6 Financial status
- 7 Foundation name
- 8 See also
- 9 References
- 10 Further reading
- 11 External links
The need for an asteroid detection program has been compared to the need for monsoon, typhoon and hurricane preparedness. While basketball-sized meteors impact the atmosphere almost daily, and compact car-sized ones about yearly, they usually burn up or explode high above the Earth with little notice. During an average 24 hour period, the Earth sweeps through some 100 million particles of interplanetary dust and debris, only a miniscule amount of which arrives at its surface as meteorites.
The larger the rock or other object, the less often it impacts the planet's atmosphere. The probability of a mid-sized asteroid (similar to the one that destroyed the Tunguska River area of Russia in 1908) hitting the Earth sometime during the 21st century is estimated at about 30%. As the Earth is now more populated than in previous eras, there is a greater risk of large casualties arising from a mid-sized asteroid impact.
The B612 Foundation is one of several organizations to propose the cataloging of near-Earth objects (NEOs) and preventative measures such as asteroid deflection; others include the international Spaceguard Foundation and NEOShield. In 2009 Anatoly Perminov, the head of the Russian Federal Space Agency, proposed a deflection mission to the near-Earth asteroid 99942 Apophis, which at the time had been thought to pose a risk to the planet.
Asteroid deflection workshop
The Foundation evolved from of a one-day workshop on asteroid deflection strategies during October 2001, organized by Dutch astrophysicist Piet Hut along with physicist and former U.S. astronaut Ed Lu, presented at NASA's Johnson Space Center in Houston, Texas. Twenty researchers participated, principally from various NASA facilities across the United Stated 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. The seminar participants included Rusty Schweickart, a former Apollo astronaut, and Clark Chapman, a planetary scientist.
From 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 engined pusher vehicle on the asteroid's surface was seen as promising, an early proposal that would later encounter a number of technical obstacles. Nuclear explosives were seen as "too risky and unpredictable" for a variety of reasons, warranting the view that gently altering an asteroid's trajectory thorough space was the safest approach—but was a method also requiring years of advance warning to successfully carry out. Among the proposed experimental research missions discussed was the alteration of an asteroid's spin rate, and also changing the orbit of one part of a binary asteroid pair.
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, with its first goal being to "significantly alter the orbit of an asteroid in a controlled manner". Schweickart became an early public face of the foundation and served as Chair on its board of directors. 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 objects (NEOs) that can poise 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. 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 planetary protection, not being permitted to request it. Feeling it would be imprudent to continue waiting for substantive government or United Nations action, 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 telescope, to be called Sentinel, with a goal of raising $30 to $40 million per year. 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.
In March and April of 2013, several weeks after the Chelyabinsk meteor explosion injured some 1,500 people, the 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. The difficulty of quickly intercepting an imminent asteroid threat to Earth was made apparent during the testimony:
|“||REP. STEWART: ... are we technologically capable of launching something that could intercept [an asteroid with 2 years of advance warning]? ...
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 ...
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), from an average of about $4 M/year between 2002 and 2010.
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) Centre for Planetary Science and Exploration. Dr. Brown's analysis, "A 500-Kiloton Airburst Over Chelyabinsk and An Enhanced Hazard from Small Impactors", published in the journals Science and Nature, was used to produce a short computer-animated video that was presented to the media at the Seattle Museum of Flight. 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 2000–2013 (for comparison, the nuclear bomb that destroyed Hiroshima was about equivalent to 16 kilotons of TNT blast force). Of those impacts between 2000 and 2013, eight of them were as large, or larger, than the Hiroshima bomb.
At the presentation, alongside former NASA astronauts Dr. Tom Jones and Apollo 8 astronaut Bill Anders, Foundation head Ed Lu explained that the frequency of dangerous asteroid impacts hitting Earth was from three to ten times greater than previously believed. The 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 Tunguska area of Siberia, Russia, and is attributed to the likely airburst explosion of an asteroid or comet that destroyed some 80 million trees over 2,150 square kilometres (830 sq mi) of forests. The new higher frequency of such events is interpreted to mean that "blind luck" has mainly prevented a catastrophic impact over an inhabited area that could kill millions, a point stated near the end of the B612 video.
The Sentinel Mission program is the cornerstone of the B612 Foundation's current efforts, with its preliminary design and system architecture level reviews planned for 2014, and its critical design review to be conducted in 2015. The infrared telescope would be launched atop a SpaceX Falcon 9 rocket, to be placed into a Venus-trailing Heliocentric orbit 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 objects (NEOs). From the vantage of its inner-solar system orbit around the Sun, Sentinel will be able to "pick up objects that are currently difficult, if not impossible, to see in advance from Earth", such as occurred with the Chelyabinsk meteor of 2013 that went undetected until its explosion over Chelyabinsk Oblast, Russia. With the Sentinel Mission providing 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 will calculate the risk of impact events with our planet, allowing for asteroid deflection by the use of gravity tractors to divert their trajectories away from Earth.
In order to communicate with the spacecraft while it's 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 telecommunication network.
Design and operation
Sentinel is being designed to perform continuous observation and analysis during its planned six and a half year operational life, although B612 anticipates it may continue to function for up to 10 years. Using its 51 centimetres (20 in) telescope mirror with sensors built by Ball Aerospace (makers of the Hubble Space Telescope's instruments), its mission will be to catalog 90% of asteroids with diameters larger than 140 metres (460 ft). There are also plans to catalog smaller solar system objects as well.
The space observatory will measure 7.7 metres (25 ft) by 3.2 metres (10 ft) with a mass of 1,500 kilograms (3,300 lb) and will orbit the Sun at a distance of 0.6 to 0.8 astronomical units (90,000,000 to 120,000,000 km; 56,000,000 to 74,000,000 mi) approximately the same orbital distance as Venus, employing infrared astronomy to identify asteroids against the cold of outer space. Sentinel will scan in the 7- to 15-micron wavelength band across a 5.5 by 2-degree field of view. Its sensor array will consist of 16 detectors with coverage scanning "a 200-degree, full-angle field of regard". B612, working in partnership with Ball Aerospace, is constructing Sentinel's 51 cm aluminum mirror, designed for a large field of view with its infrared sensors cooled to 40 degrees Kelvin (–233 °C) using Ball's two-stage, closed-Stirling-cycle cryocooler.
B612 aims 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, 15% Spitzer, 5% new, higher-performance 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.
Data gathered by Sentinel will 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 prove valuable for other possible future missions, such as asteroid mining.
Sentinel mission funding
B612 is attempting to raise approximately $450M to fund the development, launch and operational costs of the telescope, approximately $100M less than a single Next-Generation Bomber for the U.S. Air Force. The $450 million cost estimate is composed of $250 million to create Sentinel, plus another $200 million for 10 years of operations. In explaining the Foundations current bypassing of possible governmental grants for such a mission, 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 priority and funding that governments have assigned to asteroid threats, also stating on a different occasion "We’re the only ones taking it seriously." 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." After providing earlier Congressional testimony into the issue Schweickart was dismayed to hear from congressional staff members that, while 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".
In the aftermath of the February 2013 Chelyabinsk meteor explosion—where an approximate 20 metres (66 ft) asteroid entered the atmosphere undetected at about Mach 60, becoming a brilliant superbolide meteor before exploding over Chelyabinsk, Russia —the B612 foundation experienced a "surge of interest" in its project to detect asteroids, with a corresponding increase in funding donations. 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."
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.
Ed Lu, co-founder and CEO
Dr. Edward Tsang "Ed" Lu (Chinese: 盧傑; pinyin: Lú Jié; b. 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. He is a veteran of two 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.
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 in Honolulu, Hawaii from 1992 until 1995 before being selected for NASA's Astronaut Corps in 1994.
Lu developed a number of new theoretical advances, which have provided for the first time a basic understanding of the underlying physics of solar flares. Besides his work on solar flares he has published journal articles and scientific papers on a wide range of topics including cosmology, solar oscillations, statistical mechanics, plasma physics, near-Earth asteroids, and is also a co-inventor of the gravitational tractor concept of asteroid deflection.
In 2007 Lu retired from NASA to become the Program Manager on Google's Advanced Projects Team, and also worked with Liquid Robotics as its Chief of Innovative Applications, and at Hover Inc. as its Chief Technology Officer. 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.
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 Distinguished Service and Exceptional Service Medal, as well as the Russian Gagarin, Komorov and Beregovoy Medals.
Tom Gavin, Chair, Sentinel Standing Review Team
Thomas R. Gavin is the Chair 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 mission to Saturn, development of Genesis, Stardust, Mars 2001 Odyssey, Mars Exploration Rovers, SPITZER and Galaxy Evolution Explorer programs."
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. He received his bachelor's degree in chemistry from Villanova University in Pennsylvania in 1961.
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 space probes program, 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 Randolph Lovelace II Award for his management of all Jet Propulsion Laboratory and NASA robotic science spacecraft missions.
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. Currently on the SpaceX Safety Advisory Panel, he previously served as NASA's sole representative on the 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.
Hubbard founded 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 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 Distinguished Service Medal, and the American Institute of Aeronautics and Astronautics's Von Karman Medal.
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 Chair at the SETI Institute. 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.
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 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. He is also one of the co-discoverers of Pluto's new moons, Nix and 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 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 Telescopes. Buie also assists in the development of advanced astronomical instrumentation.
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 observatory. 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. Using a coronagraphic imaging system with one of the first charge-coupled devices available for astronomical use, they first observed Telesto in April 1980, just two months after being one of the first groups to observe Janus, also a moon of Saturn. Reitsema, as part of a different team of astronomers, observed 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.
Reitsema was a member of the Halley Multicolour Camera team on the European Space Agency 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 our sun.
Reitsema participated in the ground-based observations of 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 Observatory in Mexico, along with colleagues from the University of Maryland and the Mexican National Astronomical Observatory.
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. Main-belt 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 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 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 Mission program manager at Ball in 2007.
Troeltzsch's program management abilities include experience with spacecraft systems engineering and 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 COSTAR Space Telescope corrective optics, as well as the cryogenically-cooled instruments on the Spitzer Space Telescope.
Troeltzsch was awarded the NASA Exceptional Public Service Medal for his commitment to the success of the Kepler mission. His eduction 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.
David Liddle, Chair, Board of Directors
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 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 New York Times and the B612 Foundation. In January 2012, he also joined the board of directors of Stanford Research Institute International.
Liddle also held the Chair of the Board of Trustees for the Santa Fe Institute, a nonprofit theoretical research center, from 1994–1999, and served on the U.S.'s DARPA Information, Science and Technology Committee. Additionally, he was Chair of the Computer Science and Telecommunications Board of the 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 Senior Fellow of the Royal College of Art in London, England.
Board of Directors
As of 2014 the B612 Foundation's board includes Geoffrey Baehr (formerly with Sun Microsystems and U.S. Venture Partners), plus Doctors Chapman, Piet Hut, Ed Lu (also CEO, see Leadership, above), David Liddle (Chair, see Leadership, above), and Dan Durda, a planetary scientist.
Rusty Schweickart, co-founder and Chair Emeritus
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 U.S. Apollo astronaut, research scientist, Air Force pilot, plus business and government executive. Schweickart, chosen in NASA's third astronaut group, is best known as the Lunar Module pilot on the Apollo 9 mission, the spacecraft's first manned 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 star tracking and the stabilization of stellar images, a crucial requirement for space navigation. Schweickart's education includes a B.Sc. in 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".
After serving as the backup commander of NASA's first manned 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's Energy Commission for five and a half years.
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. Tom Jones, NASA's Advisory Council’s Task Force on Planetary Defense. In 2002 he co-founded B612, also serving as its Chair.
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's received are the Federation Aeronautique Internationale's De la Vaulx Medal in 1970 for his Apollo 9 flight, both of NASA's Distinguished Service Medal and 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.
Clark Chapman, co-founder and Board Member
Dr. 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: 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 and Near-Earth Asteroid Rendezvous space missions."
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 sciences, and also served at the Planetary Science Institute in Tucson, Arizona. He is currently on faculty at the Southwest Research Institute of Boulder, Colorado.
Dan Durda, Board Member
Dr. Daniel David "Dan" Durda (b. October 26, 1965, Detroit, Michigan), 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." 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.
Durda is an active instrument-rated pilot who has flown numerous aircraft, including high performance F/A-18 Hornets and the F-104 Starfighters, 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."
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", Asteroid 6141 Durda is named in his honour.
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: Dr. Alexander Galitsky, a former Soviet computer scientist and B612 Founding Circle adviser; British Astronomer Royal, cosmologist and astrophysicist 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. 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 Shapiro; U.S. film director Jerry Zucker; British-U.S. balloonist Julian Nott; Dutch astrophysist 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. Tom Jones.
Tom Jones, Strategic Adviser
Dr. Thomas David "Tom" Jones (b. January 22, 1955) is a strategic adviser to B612, member of the 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, including three spacewalks to install the centerpiece of the International Space Station (ISS). His publications include Planetology: Unlocking the Secrets of the Solar System.
After graduating from the U.S. Air Force Academy where he received his B.Sc. in 1977, Jones earned a Ph.D. in Planetary Sciences 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, investigating future robotic missions to Mars, asteroids, and the outer solar system.
After a year of training following his selection by NASA he became an astronaut in July 1991. In 1994 he flew as a mission specialist on successive flights of various Space Shuttles,, running science operations on the "night shift" during STS-59, successfully deploying and retrieving 2 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 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, installing the laboratory module in a series of 3 space walks lasting over 19 hours, which marked the start of onboard scientific research at the ISS.
Among his honors are NASA's Space Flight Medal, Exceptional Service Award, Outstanding Leadership Medal, plus the Federation Aeronautique Internationale's Komarov Diploma and a NASA Graduate Student Research Fellowship.
Piet Hut, 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 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 Interdisciplinary Studies at the Institute for Advanced Study in Princeton, New Jersey, 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." Dr. Hut was an early adviser to Lu and served as a founding member of the B612 Foundation’s Board of Directors.
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". 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 Asteroid 17031 Piethut honoring his work in planetary dynamics and for his co-founding of B612.
A number of methods have been devise 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. Among the methods that can accomplish this are:
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 unmanned spacecraft hovering over an asteroid to gravitationally pull the latter into a non-threatening orbit. The method functions due to the spacecraft and the asteroid mutually attracting one another due to gravity. If the spacecraft counters the gravitational attraction towards the asteroid by the use of, for example an 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.
While slow, this method has the advantage of working irrespective of an asteroid's composition (it would be effective even on a comet or loose rubble pile), or the object's spin 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 Earth. It means the threat for the entire planet might be minimized at a temporary cost of some specific states' security. Schweickart views that choosing the manner and direction the asteroid should be "dragged" may be a difficult international decision.
A 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." 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.
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 small 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 have 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 succeessful U.S. mission that crashed its Deep Impact probe into 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. In the 2000s the European Space Agency (ESA) began studying the design of a space mission named Don Quijote, which, if flown, would had 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: 2002 AT4 and (10302) 1989 ML. 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 annouced at the 44th annual Lunar and Planetary Science Conference that its mission would be combined into a joint ESA-NASA 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. AIDA's new target, a component of binary asteroid 65803 Didymos, will be impacted at a velocity of 22,530 km/h (14,000 mph)
A NASA analysis of deflection alternatives, conducted in 2007, stated: "Non-nuclear kinetic impactors are the most mature approach and could be used in some deflection/mitigation scenarios, especially for NEOs that consist of a single small, solid body."
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 Mountain View, California; they were previously located in Tiburon, California.
The B612 Foundation is named in tribute to the home asteroid of the eponymous hero of Antoine de Saint-Exupéry's best-selling philosophical fable of Le Petit Prince (The Little Prince). 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.
That experience later contributed, in 1943, to his literary creation of Asteroid B-612 in his philosophical fable of a little prince fallen to Earth, with the home 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 asteroid moon, Petit-Prince, discovered in 1998 is named in part after The Little Prince.
- "Foundation History". B612 Foundation. Retrieved April 15, 2012.
- Griggs, Mary Beth. Avoiding Armegeddon: The Hunt is on For Dangerous Asteroids, USA Today, October 6, 2013. Retrieved June 30, 2014.
- Lufkini, Bryan. The Asteroid Stalker (summarized web article version), Wired, April 2014, p. 37; and This Ex-Astronaut Is Stalking Asteroids to Save Civilization, Wired, April 2014, p. 38. Retrieved June 30, 2014 and July 8, 2014 respectively.
- Sastrowardoyo, Hartriono B. Scientists: East Coast Meteoroid Strike Unlikely, New Jersey: Ashbury Park Press, March 27, 2013; with contribution by Ledyard King, Gannett Washington Bureau. Retrieved from USAToday.com website, June 30, 2014.
- Powell, Corey S. How to Deflect a Killer Asteroid: Researchers Come Up With Contingency Plans That Could Help Our Planet Dodge A Cosmic Bullet, Discover website, September 18, 2013 (subscription required), and in print as "How to Dodge a Cosmic Bullet", October 2013. Retrieved July 15, 2014.
- How do you stop an asteroid hitting Earth?, The Economist website, July 3, 2013. Retrieved July 5, 2014.
- Barry, Ellen. Russia to Plan Deflection of Asteroid From Earth, The New York Times website, December 30, 2009 and in print on December 31, 2009, p. A6 of the New York edition. Retrieved June 26, 2014.
- B612 History, B612 Foundation, March 22, 2004. Retrieved from Archive.org, July 22, 2014.
- Cain, Fraser. Homing Beacon for an Asteroid, Universe Today, June 7, 2005. Retrieved July 4, 2014.
- Hut, Piet. Asteroid Deflection: Project B612, Piet Hut webpage at the Institute for Advanced Study website. Retrieved July 24, 2014.
- Atkinson, Nancy (October 14, 2010). "Is the World Ready for An Astero metid Threat? Apollo’s Schweickart Pushes for Action". Universe Today. The Universe Today Team. Retrieved before April 15, 2012.
- Binzel, Richard P.; Chapman, Clark R.; Johnson, Lindley N.; Jones, Thomas D.; Schweickart, Russell L.; Wilcox, Brian; Yeomans, Donald K.; Siegel, Bette. Report of the NASA Advisory Council Ad Hoc Task Force on Planetary Defense, NASA Advisory Council, October 6, 2010, p. 10, Report: TFPD FINAL Report to NAC 10-6-10_v3 (PDF).
- Schweickart, Russell; Johnson, Erik T. (illustrator) Humans to Asteroids: Watch Out!, The New York Times website, October 25, 2010, and in print on October 26, 2010, p. A29 of the New York edition. Retrieved July 4, 2014.
- Powell, Corey S. "Developing Early Warning Systems for Killer Asteroids", Discover, August 14, 2013, pp. 60–61 (subscription required).
- Lovgren, Stefan. Asteroid False Alarm Shows Limits of Alert Systems, National Geographic News, March 8, 2004. Retrieved July 30, 2014.
- B612 Foundation Receives New Funding and Strategic Support From Prominent Leaders in Business, Entertainment, Science and Technology, B612 Foundation, September 19, 2012. Retrieved July 11, 2014.
- Norris, Guy (2013-04-09). "Ball Aerospace Ramps Up Sentinel Asteroid Search Mission". Aviation Week & Space Technology. Retrieved 2013-04-11.
- Smith, Marcia S. Third Congressional Hearing on Asteroid Threat Coming Up Next Week, SpacePolicyOnline.com website, April 4, 2013. Retrieved July 29, 2014.
- U.S.Congress (19 March 2013 and 10 April 2013). "Threats From Space: a Review of U.S. Government Efforts to Track and mitigate Asteroids and Meteors (Part I and Part II) - Hearing Before the Committee on Science, Space, and Technology House of Representatives One Hundred Thirteenth Congress First Session". United States Congress. p. 147. Retrieved 3 May 2014.
- Johnson, Lindley. NEO Observations Program in "United States Government Policy and Approach Regarding Planetary Defense", Agency Grand Challenge Seminar Series, Near Earth Object Programs Executive, NASA HQ, February 28, 2014, pp. 7, 15 (PDF).
- Chowdhury, Sudeshna. What Are Odds an Asteroid Will Level a Major City? Higher Than You Might Think, Say Researchers, Christian Science Monitor – via HighBeam Research (subscription required), April 23, 2014. Retrieved July 11, 2014.
- Brown, P.G., with J. D. Assink, L. Astiz, R. Blaauw, M. B. Boslough, J. Borovička, N. Brachet, D. Brown, M. Campbell-Brown, L. Ceranna,W. Cooke, C. de Groot-Hedlin, D. P. Drob, W. Edwards, L. G. Evers, M. Garces, J. Gill, M. Hedlin, A. Kingery, G. Laske, A. Le Pichon, P. Mialle, D. E. Moser, A. Saffer, E. Silber, P. Smets, R. E. Spalding, P. Spurný, E. Tagliaferri, D. Uren, R. J. Weryk, R. Whitaker & Z. Krzeminski. "A 500-Kiloton Airburst Over Chelyabinsk and An Enhanced Hazard from Small Impactors", Nature, Vol. 503, pp. 238–241, November 14, 2013 and published online November 6, 2013, doi:10.1038/nature12741 (subscription required).
- Carreau, Mark. Silicon Valley Nonprofit Amplifies Warnings Of Asteroid Hazard, Aviation Week Intelligence Network website, April 23, 2014. Retrieved July 1, 2014.
- Seattle Museum Of Flight To Host Astronauts On Earth Day For Special Program On Protecting Earth From Dangerous Asteroids (media release), B612 Foundation website, April 17, 2014. Retrieved July 7, 2014.
- B612 Impact Video, B612 Foundation.
- Early-Warning Telescope Could Detect Dangerous Asteroids, NBC Nightly News, April 22, 2014 (video, Flash required, 2:27)
- "B612 Foundation Releases Video at Seattle Museum of Flight Earth Day Event Showing Evidence of 26 Multi-Kiloton Asteroid Impacts Since 2001". B612 Foundation. 22 April 2014. Retrieved 23 April 2014.
- Fountain, Henry. Better Asteroid Detection Is Needed, Experts Say, The New York Times website, March 20, 2013, and in print on March 21, 2013, p. A3 of the New York edition. Retrieved June 26, 2014.
- "PROJECT B612: Deflecting an Asteroid using Nuclear-Powered Plasma Drive Propulsion (home page)". Project B612 (now B612 Foundation). November 26, 2002. Retrieved April 15, 2012.
- "Sentinel Factsheet" (PDF). B612 Foundation. February 2013. Retrieved July 11, 2014.
- Broad, William J. Vindication for Entrepreneurs Watching Sky: Yes, It Can Fall, The New York Times website, February 16, 2013 and in print on February 17, 2013, p. A1 of the New York edition. Retrieved June 27, 2014.
- "The Sentinel Mission". B612 Foundation. Retrieved September 19, 2012.
- "Sentinel". Ball Current Programs. Ball Aerospace. 2013. Retrieved 2013-08-02.
- Wall, Mike (July 10, 2012). "Private Space Telescope Project Could Boost Asteroid Mining". Space.com. Retrieved September 14, 2012.
- Smith, Chris A. Doomsday 1: An Asteroid Wiped Out the Dinosaurs—Will We Be Next?, University of California, Berkeley Alumni Association website, June 2014. Retrieved from alumni.berkeley.edu on June 26, 2014.
- Chang, Kenneth. More Asteroid Strikes Are Likely, Scientists Say, The New York Times website, November 6, 2013, and in print on November 7, 2013, p. A12 of the New York edition. Retrieved June 26, 2014.
- Schwartz, John. The Limits of Safeguards and Human Foresight, The New York Times website, March 11, 2011 and in print on March 13, 2011, p. WK1 of the New York edition; also within The Best-Laid Plans, The New York Times website, March 13, 2011. Both retrieved June 26, 2014.
- Revkin, Andrew C. Dot Earth | Apocalypse Then. Next One, When? (blog), The New York Times website, June 30, 2008. Retrieved June 26, 2014.
- Moskowitz, Clara. United Nations to Adopt Asteroid Defense Plan, Scientific American website, October 28, 2013 (subscription required).
- Burrows, William E. Near Earth Objects: Averting A Collision With Asteroids, Miami Herald, June 15, 2014. Retrieved June 26, 2014.
- Cooke, William (15 February 2013). "Orbit of the Russian Meteor". NASA blogs. Retrieved 17 February 2013.
- Avery, Greg. Car Cameras A Boost For Ball Aerospace's Killer-Asteroid Spotter, Denver Business Journal, Apr 9, 2013. Retrieved July 15, 2014.
- Fountain, Henry (2013-03-26). "A Clearer View of the Space Bullet That Grazed Russia". The New York Times. p. D3. Retrieved 2013-03-27.
- Sentinel Mission Leadership, B612 Foundation website. Retrieved July 11, 2014.
- NASA (2000). "Ed Lu Biography". NASA. Retrieved October 6, 2008.
- Edward T. Lu and Stanley G. Love (10 November 2005), Gravitational Tractor For Towing Asteroids, Nature 438:177–178, doi:10.1038/438177a. Also, see astro-ph/0509595 in the arXiv.
- Beutel, Allard (2007-08-10). "Astronaut Ed Lu Leaves NASA". NASA. Retrieved 2007-08-12.
- "Google Unveils New Maps Features Amid Apple Fight". Silicon Valley News. June 6, 2012. Retrieved July 1, 2012.
- Our Team | Ed Lu, CEO and Co-Founder, B612 Foundation, SentinelMission.org website. Retrieved June 29, 2014.
- ASK Talks With Tom Gavin, NASA: ASK Magazine, Iss. 17, April 1, 2004.
- About JPL: Thomas R. Gavin, Director for Solar System Exploration (Interim), NASA, Jet Propulsion Laboratory website. Retrieved July 12, 2014. Note: This material includes verbatim text from the noted website, a work of the United States Government in the public domain and not under copyright.
- Associate Director Honored by American Astronautical Society (media release), NASA, October 13, 2003.
- Our Team | Tom Gavin, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.
- Dr. G. Scott Hubbard (biography), NASA, NAC Science Committee, updated to April 4, 2014. Retrieved July 13, 2014.
- SpaceX, Aiming At Carrying NASA Crews, Names Safety Panel, SocCalTech.com website, March 29, 2012.
- 'Exploring Mars', by Scott Hubbard (book review), San Francisco Chronicle website, February 29, 2012.
- G. Scott Hubbard (biography), Stanford University. Retrieved July 13, 2014.
- Bibliography of Marc W. Buie, Southwest Research Institute, January 13, 2014.
- "Pluto's Portrait: Even The Mighty Hubble Has To Strain To See This Tiny, Distant Planet", Air & Space Smithsonian magazine, June/July 1996, Iss., p 60.
- Avery, Greg. Ball Aerospace To Build First Private, Deep-Space Mission, Denver Business Journal, July 6, 2012. Retrieved July 15, 2014.
- Larissa at Nine Planets, Students for the Exploration and Development of Space (SEDS), Lunar and Planetary Laboratory, University of Arizona, October 29, 1997; via archive.org
- Goldman, Noah. Creating Colorful Comets, NASA, Science Mission Directorate, October 17, 2013.
- Zauderer, B. A.; Walsh, K. J.; Vázquez, R.; Reitsema, H. Deep Impact observations from San Pedro Martir, American Astronomical Society, Meeting 207, #04.22; Bulletin of the American Astronomical Society, Vol. 37, p.1157, December 2005.
- Solomon, Benjamin. AIAA Rocky Mountain — Sentinel Program, Interstellar Space Exploration Technology Initiative, January 27, 2013. Retrieved July 15, 2014.
- Our Team | John Troeltzsch, B612 Foundation, SentinelMission.org website. Retrieved July 15, 2014.
- David Liddle: U.S. Venture Partners (biography), Stanford University, Stanford Technology Ventures Program, Stanford Entrepreneurship Corner, October 30, 2006. Retrieved July 9, 2014.
- Our Team | David Liddle, B612 Foundation, SentinelMission.org website. Retrieved June 30, 2014.
- "David Liddle Joins SRI International Board of Directors". SRI International. 2012-01-04. Retrieved 2013-06-13.
- SFI Bulletin 14 (2), Santa Fe Institute, Fall 1999, p. 27, retrieved 2009-02-27
- "The Foundation". B612 Foundation. Retrieved April 15, 2012.
- Board of Directors, B612 Foundation website. Retrieved 12 July 2014.
- Biographical Data: Russell L. Schweickart, NASA Astronaut (Former), NASA, Lyndon B. Johnson Space Center, September 2006. Accessed July 7, 2011.
- Kramer, Jill. Scanning The Skies, San Rafael, Marin County, California: Pacific Sun, July 7, 2004 – via HighBeam Research (subscription required); also published online as Rusty Schweickart: Space Man.
- McBarton, Bob (2010), "Former Apollo Astronaut Rusty Schweickart on the Dangers of Near Earth Asteroids and Objects", The Luncheon Society, retrieved August 16, 2011
- Our Team | Rusty Schweickart, Chair Emeritus, B612 Foundation, SentinelMission.org website. Retrieved June 29, 2014.
- MIT-alum Alumni list, MIT, Massachusetts Institute of Technology webpage.
- Our Team | Clark Chapman, B612 Foundation, SentinelMission.org website. Retrieved June 30, 2014.
- Biographical Data: Daniel David Durda (Ph.D.), Southwest Research Institute. Retrieved July 7, 2014.
- Our Team | Cark Chapman, B612 Foundation, SentinelMission.org website. Retrieved July 7, 2014.
- Strategic Advsors, B612 Foundation. Retrieved July 21, 2014.
- Spence, Rick. World Entrepreneurs show you the way to greater impact, Financial Post, June 12, 2014. Retrieved June 26, 2014.
- Our Team | Tom Jones, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.
- Jones, Tom; Stofan, Ellen Renee. Planetology: Unlocking the Secrets of the Solar System, National Geographic, 2008, ISBN 1426201214, ISBN 978-1426201219.
- Jones, Thomas David. "NASA Advisory Council (NAC) Biographical Data". NASA. Retrieved 2009-07-14.
- Emeriti page for Piet Hut, Institute for Advanced Study, retrieved December 7, 2011.
- Program in Interdisciplinary Studies individual homepage page for Piet Hut, Institute for Advanced Study.
- Our Team | Piet Hut, B612 Foundation, SentinelMission.org website. Retrieved July 4, 2014.
- Curriculum Vitae: Piet Hut, Princeton, New Jersey: Institute for Advanced Study, 2014. Retrieved July 4, 2014.
- Curriculum Vitae: Piet Hut, Institute for Advanced Study, Retrieved July 25, 2014.
- Schweickart, Russell L.; Lu, Edward T.; Hut, Piet; Chapman, Clark. The Asteroid Tubboat, Scientific American website, November 2003 (subscription required).
- Amos, Jonathan. NEOShield to Assess Earth Defence, BBC News, January 20, 2012.
- Madrigal, Alexis. Saving Earth From an Asteroid Will Take Diplomats, Not Heroes, Wired, December 17, 2009.
- Near-Earth Object Survey and Deflection: Analysis of Alternatives: Report to Congress, March 2007, NASA, Near Earth Object Program, March 2007, updated July 24, 2014.
- JPL Evaluation of Gravity Tractor: Summary Statement by B612 Foundation regarding its contract with JPL to conduct a detailed performance analysis of a transponder equipped Gravity Tractor spacecraft, B612 Foundation, September 24, 2008.
- Reuters (July 7, 2005). "After US, China plans "Deep Impact" mission". The Economic Times. Archived from the original on August 30, 2005. Retrieved May 11, 2009.
- ESA selects targes for asteroid deflecting mission Don Quijote
-  Asteroid Impact Deflection Assessment AIDA study (ESA), 19 December 2012
- Asteroid deflection mission seeks smashing ideas, European Space Agency (ESA), January 15, 2013.
- Asteroid Deflection Mission AIDA Set To Crash Two Spacecraft Into Space Rock In 2022 Huffington Post, March 25, 2013.
- Mone, Gregory (January 1, 2006). "Rear-ending Rocks in Space". Popular Science. Bonnier Group. Retrieved April 15, 2012.
- Greenfieldboyce, Nell (November 10, 2005). "Nudging Killer Asteroids Off Course". National Public Radio. Retrieved August 26, 2010.
- Hausler, Pete. Wind, Sand and Stars by Antoine de Saint Exupéry, Post Road Magazine website, Issue No. 8, Spring–Summer 2004. Retrieved July 29, 2014.
- Murphy, Kate. Ed Lu: Catching Up With the Former Astronaut Ed Lu, The New York Times Sunday Review website, June 21, 2014 and on June 22, 2014, p. SR2 of the New York edition. Retrieved June 26, 2014.
- Schmadel, Lutz D. Dictionary of Minor Planet Names, p. 895.
- William J. Merlin, et al. (2000). "On a Permanent Name for Asteroid S/1998(45)1" (TXT). Department of Space Studies, Southwest Research Institute. Retrieved 9 November 2011.
- Lewis, John S. Comet And Asteroid Impact Hazards On A Populated Earth: Computer Modeling, Volume 1, Academic Press, 2000, ISBN 0124467601, ISBN 978-0124467606
- Powell, Corey S. "How to Deflect a Killer Asteroid: Researchers Come Up With Contingency Plans That Could Help Our Planet Dodge A Cosmic Bullet", Discover, September 18, 2013, pp. 58–60 (subscription).
- Schweickart, Lu, Hut and Chapman. "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. Rogue Asteroids and Doomsday Comets: The Search for the Million Megaton Menace That Threatens Life on Earth, Wiley & Sons, 1995, , ISBN 0471193380, ISBN 978-0-4711-9338-8.
- Official website (current)
- B612 Foundation: early website homepage (archived)
- B612 Foundation: Sentinel Mission Factsheet (Feb. 2013, PDF)
- Dr. Ed Lu at TEDxMarin: Changing the Course of the Solar System (video, 14:04)
- NBC Nightly News: Early-Warning Telescope Could Detect Dangerous Asteroids, broadcast April 22, 2014 (video, 2:27)
- 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)
- Dr. Ed Lu Congressional Testimony, Washington, D.C., March 20, 2013, United States Senate Sub-Committee on Science and Space: "Assessing the Risks, Impacts and Solutions for Space Threats" (video, 23:49)
- PBS NOVA | Asteroid: Doomsday or Payday?, originally broadcast November 20, 2013; includes interviews with B612 Foundation staff (program description here, video, 53:24)