
The term Spaceguard loosely refers to a number of efforts to discover,
catalogue, and study
near-Earth object
A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun ( perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit a ...
s (NEO), especially those that may impact Earth (
potentially hazardous objects).
Asteroids are discovered by
telescope
A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...
s which repeatedly
survey large areas of sky. Efforts which concentrate on discovering NEOs are considered part of the "Spaceguard Survey," regardless of which organization they are affiliated with.
A number of organizations have also raised related discussions and proposals on
asteroid-impact avoidance.
History
Arthur C. Clarke coined the term in his novel ''
Rendezvous with Rama'' (1973) where "Project Spaceguard" was the name of an
early warning system created following a fictional catastrophic
asteroid impact
An impact event is a collision between astronomical objects causing measurable effects. Impact events have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effe ...
.
[Michael Paine (2000-04-26)]
"Bigger Telescopes Seek Killer Asteroids"
''Space.com
Space.com is an online publication focused on outer space, space exploration, astronomy, skywatching and entertainment, with editorial teams based in the United States and United Kingdom. Launched on July 20, 1999, the website offers live coverag ...
'' (accessed on 2010-06-26) This name was later adopted by a number of real life efforts to discover and study near-
Earth
Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...
objects. The name was used for the Survey "with the permission and encouragement of Clarke." A 1992
US Congressional study produced a "Spaceguard Survey Report"
[ David Morrison (1992),]
The Spaceguard Survey Report
",
NASA Studies
'' at Asteroid and Comet Impact Hazards, NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
Ames Research Center
The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laborat ...
. which led to a mandate that
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
locate 90% of near-Earth
asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...
s larger than 1 km within 10 years. This is often referred to as the "Spaceguard Goal." A number of efforts which receive money through NASA are all considered to be working on the "Spaceguard Project."
The effect of the impact of
Comet Shoemaker–Levy 9 to Jupiter in July 1994 created a greater perception of importance to the detection of near Earth objects. As David Levy stated in an interview "The giggle factor disappeared after Shoemaker-Levy 9." He was referring to the contemporary attitude that
extinction level events were so improbable that those advocating for research for detection and possible deflection methods were only paranoid alarmists. The impact of one of its fragments created a giant dark spot on Jupiter over 12,000 km across, and was estimated to have released an energy equivalent to 6
teratons of TNT (600 times the world's nuclear arsenal). After the impact of Comet Shoemaker-Levy 9, asteroid detection programs all over the world received greater funding.
The Working Group on Near-Earth Objects (WGNEO) of the
International Astronomical Union
The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...
held a workshop in 1995 entitled ''Beginning the Spaceguard Survey''
[Beginning the Spaceguard Survey](_blank)
, Vulcano Workshop (1995), IAU Working Group on Near-Earth Objects. (accessed on 2010-06-26) which led to an international organization called the
Spaceguard Foundation. Subsequently, there have been Spaceguard associations or foundations formed in countries around the world to support the ideas of discovering and studying near-Earth objects. Generally, the Spaceguard organizations formed within individual countries are associated with the international foundation or with the NASA efforts only by name, common interests, and similar goals.
The initial Spaceguard Goal was achieved, although in slightly longer than 10 years. An extension to the project gave NASA the mandate of reducing the minimum size at which more than 90% of near-Earth asteroids are known to 140 m.
Observations
The
2002 Eastern Mediterranean event and the
Chelyabinsk meteor (Russia, February 2013) were not detected in advance by any Spaceguard effort. On October 6, 2008, the 4-meter
2008 TC3 meteoroid
A meteoroid ( ) is a small rocky or metallic body in outer space.
Meteoroids are distinguished as objects significantly smaller than ''asteroids'', ranging in size from grains to objects up to wide. Objects smaller than meteoroids are classifie ...
was detected by the
Catalina Sky Survey (CSS) 1.5 meter telescope at
Mount Lemmon, and monitored until it hit the Earth the next day.
New survey projects, such as the
Asteroid Terrestrial-impact Last Alert System
The Asteroid Terrestrial-impact Last Alert System (ATLAS) is a robotic astronomical survey and early warning system optimized for detecting smaller near-Earth objects a few weeks to days before they Impact event, impact Earth.
Funded by NASA, an ...
(ATLAS) program operated by the
University of Hawaii
A university () is an educational institution, institution of tertiary education and research which awards academic degrees in several Discipline (academia), academic disciplines. ''University'' is derived from the Latin phrase , which roughly ...
, aim to greatly increase the number of small (down to approximately 10 m) impactors that are discovered before
atmospheric entry
Atmospheric entry (sometimes listed as Vimpact or Ventry) is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. Atmospheric entry may be ''uncontrolled entr ...
—typically with days to weeks of warning, enabling evacuations of the affected areas and damage mitigation planning. This is in contrast to other surveys which focus on finding much larger (greater than 100 m) objects years to decades before any potential impacts, at times when they could potentially still be deflected away from Earth.
Another short-term warning system is the NASA Scout program that came into operation in 2016.
On October 19, 2017, one of the Survey telescopes,
Pan-STARRS
The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1; List of observatory codes, obs. code: IAU code#F51, F51 and Pan-STARRS2 obs. code: IAU code#F52, F52) located at Haleakala Observatory, Hawaii, US, consists of astronomical ...
1, discovered the first interstellar asteroid,
'Oumuamua.
The United Kingdom also hosts the self-styled Spaceguard Centre which conducts astrometric research (MPC code J26) and is open to the general public daily, but it is not affiliated with or supported by any public body.
Issues
According to
Dr. Michael F. A'Hearn, a typical mission would take too long from approval to launch if there was an emergency:
Lack of a master plan and dangers of false alarms have been pointed out by Stefan Lövgren.
[Stefan Lovgren (2004-03-08),]
Asteroid False Alarm Shows Limits of Alert Systems
''National Geographic News''. (accessed on 2010-06-26)
See also
*
Spaceguard Foundation
The Spaceguard Foundation (SGF) is a private organization based in Frascati, Italy, whose purpose is to study, discover and observe near-Earth objects (NEO) and protect the Earth from the possible threat of their collision. The foundation is no ...
**
Bisei Spaceguard Center
**
Japan Spaceguard Association
*
Asteroid-impact avoidance (includes list of survey projects)
*
Asteroid impact prediction
Asteroid impact prediction is the prediction of the dates and times of asteroids impacting Earth, along with the locations and severities of the impacts.
The process of impact prediction follows three major steps:
# Discovery of an asteroid an ...
*
B612 Foundation
The B612 Foundation is a private nonprofit foundation headquartered in Mill Valley, California, United States, dedicated to planetary science and planetary defense against asteroids and other near-Earth object (NEO) impacts. It is led mainly ...
*
NEOShield
*
Planetary Defense Coordination Office
*
Impact event
An impact event is a collision between astronomical objects causing measurable effects. Impact events have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effe ...
**
Tunguska event
The Tunguska event was a large explosion of between 3 and 50 TNT equivalent, megatons that occurred near the Podkamennaya Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia, on the morning of 30 June 1908. The explosion over ...
, 1908
*
List of meteor air bursts
**
Chelyabinsk meteor, Russia, February 2013
References
Further reading
* Air Force 2025.
Planetary Defense: Social, Economic, and Political Implications United States Air Force
The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...
, Air Force 2025 Final Report webpage, December 11, 1996.
* Daugherty, Laura and Emily Van Yuga
What Damage Have Impacts Done to Humans in Recorded History?(Geol 117: Meteorite Impacts in Space and Time), Oberlin College Geology Department,
Oberlin College
Oberlin College is a Private university, private Liberal arts colleges in the United States, liberal arts college and conservatory of music in Oberlin, Ohio, United States. Founded in 1833, it is the oldest Mixed-sex education, coeducational lib ...
, May 11, 2001.
* Halliday, I., A.T. Blackwell, and A.A. Griffin. "Meteorite Impacts on Humans and Buildings", ''
Nature
Nature is an inherent character or constitution, particularly of the Ecosphere (planetary), ecosphere or the universe as a whole. In this general sense nature refers to the Scientific law, laws, elements and phenomenon, phenomena of the physic ...
'', pp. 318–317.
ib. of Yau et al.* Lapaz, L. "Effects of Meteorites on the Earth", ''Advances in Geophysics'', Vol. 4, pp. 217–350.
ib. of Yau et al.* Lewis, J.S
Rain of Iron and Ice: The Very Real Threat of Comet and Asteroid Bombardment Reading, MA: Addison-Wesley Pub. Co., 1996; Basic Books, 1997, .
BIS* Nield, Ted
Don't wrong the meteorite: Ted Nield thinks it's time to reassess our attitude to cosmic impacts. Meteorites are our friends Geoscientist Online,
The Geological Society
The Geological Society of London, known commonly as the Geological Society, is a learned society based in the United Kingdom. It is the oldest national geological society in the world and the largest in Europe, with more than 12,000 Fellows.
Fe ...
, October 2008.
* Norton, O.R. "''Rocks from Space''". Missoula Montana: Mountain Press Publishing Company, 1998.
ourse textbook
* Paine, M.P
Bigger Telescopes Seek Killer AsteroidsArchive from Space.com April 2000.
* Reimold, W. U. and R. L. Gibson, Anton Pelser, Mauritz Naudé, Kevin Balkwill
Meteorite impact!: the danger from space and South Africa's mega-impact the Vredefort structure Chris van Rensburg, 2005, .
* "Special Report: Death and Property Damage Due to Meteor Destruction", UFO Research: Cincinnati!, November, 1998.
* Swindel, G.W. Jr., and W.B. Jones. ''Meteoritics'', Vol. 1, pp. 125–132.
ib. of Lapaz 1958
* Webb, S.K.
A Novel Measure of Meteorite Flux,
eteorite-listHow Many Meteorites Fall?, November 30, 2000.
* Worthey, G
Meteor Near Misses and Strikes St. Ambrose University Astronomy, 11 October 1999.
* Yau, K., Weissman, P., & Yeomans, D
Meteorite Falls In China And Some Related Human Casualty Events ''
Meteoritics'', 1994, Vol. 29, No. 6, pp. 864–871, , bibliographic code: 1994Metic..29..864Y.
External links
Spaceguard Central Node
NASA's Near-Earth Office Program David Morrison Tuesday, August 1, 2000 (Discovery statistics by 2000)
Saturday, February 9, 2002 (Status report by 2002)
UK Spaceguard CentrePlanetary Defense Foundation
{{Portal bar, Astronomy, Stars, Spaceflight, Outer space, Solar System
Astronomical surveys
Planetary defense organizations