Lincoln Near-Earth Asteroid Research
Encyclopedia
The Lincoln Near-Earth Asteroid Research (LINEAR) project is a cooperative project between the United States Air Force
, NASA
, and MIT
's Lincoln Laboratory
for the systematic discovery and tracking of near-Earth asteroid
s. LINEAR was responsible for the majority of asteroid detections since 1998 until overtaken by the Catalina Sky Survey
. , LINEAR had detected 226,193 new objects of which at least 2019 were near-Earth asteroids and 236 were comet
s. All of LINEAR's discoveries were made using robotic telescope
s.
The initial field tests go back to 1972. In the early 1980s, a prototype was built, the Lincoln Laboratory ETS (Experimental Test System), New Mexico (MPC observatory code 704). The LINEAR project began operating a near-Earth object
(NEO) discovery facility using a one-meter aperture Ground-based Electro-Optical Deep Space Surveillance (GEODSS) telescope
in 1996. Such wide-field Air Force telescopes were designed for optical observation of Earth orbital spacecraft. The GEODSS instruments used by the LINEAR program are located at the Lincoln Laboratory's experimental test site in the White Sands Missile Range
at Socorro, New Mexico
. Data is then sent to the Lincoln Laboratory at Hanscom Air Force Base
in Lexington, Massachusetts
.
Between March and July 1997, a 1024 × 1024 charge-coupled device
(CCD) pixel
detector was used in field tests and, while this CCD detector filled only about one fifth of the telescope's field of view
, four near-earth objects were discovered. In October 1997, a large format CCD, of 1960 × 2560 pixels, which covered the telescope's two-square degree
field of view, was employed successfully to discover a total of nine new near-Earth objects. Five more NEOs were added between November 1997 through January 1998, when both the small and large format CCD detectors were employed.
Beginning in October 1999, a second one-meter telescope was added to the search effort. In 2002, a third telescope of 0.5 meter aperture
was brought on-line to provide follow-up observations for the discoveries made by the two 1-meter search telescopes. Currently, LINEAR telescopes observe each patch of sky five times in one evening with most of the efforts going into searching along the ecliptic plane
where most NEOs would be expected. The sensitivity of their CCDs, and particularly their relatively rapid read out rates, allows LINEAR to cover large areas of sky each night. Currently, the LINEAR program is responsible for the majority of NEO discoveries.
The project's principal investigator is Grant Stokes, and co-investigators include Jenifer Evans and Eric Pearce.
In addition to discovering hundreds of thousands of asteroids (225,957 as of December 31, 2007), LINEAR is also credited with the discovery, or co-discovery, or rediscovery of several periodic comets, including 11P/Tempel-Swift-LINEAR
, 146P/Shoemaker-LINEAR, 148P/Anderson-LINEAR, 156P/Russell-LINEAR, 158P/Kowal-LINEAR
, 160P/LINEAR
(LINEAR 43), 165P/LINEAR
(LINEAR 10), and 176P/LINEAR (LINEAR 52, 118401 LINEAR: one of only five objects classified both as comets and asteroid
s).
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
, NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
, and MIT
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...
's Lincoln Laboratory
Lincoln Laboratory
MIT Lincoln Laboratory, located in Lexington, Massachusetts, is a United States Department of Defense research and development center chartered to apply advanced technology to problems of national security. Research and development activities focus on long-term technology development as well as...
for the systematic discovery and tracking of near-Earth asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
s. LINEAR was responsible for the majority of asteroid detections since 1998 until overtaken by the Catalina Sky Survey
Catalina Sky Survey
Catalina Sky Survey is a project to discover comets and asteroids, and to search for Near-Earth objects. More specifically, to search for potentially hazardous asteroids , that may pose a threat of impact.-Mission:...
. , LINEAR had detected 226,193 new objects of which at least 2019 were near-Earth asteroids and 236 were comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
s. All of LINEAR's discoveries were made using robotic telescope
Robotic telescope
A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated by a human, even if a human has to initiate the...
s.
The initial field tests go back to 1972. In the early 1980s, a prototype was built, the Lincoln Laboratory ETS (Experimental Test System), New Mexico (MPC observatory code 704). The LINEAR project began operating a near-Earth object
Near-Earth object
A near-Earth object is a Solar System object whose orbit brings it into close proximity with the Earth. All NEOs have a perihelion distance less than 1.3 AU. They include a few thousand near-Earth asteroids , near-Earth comets, a number of solar-orbiting spacecraft, and meteoroids large enough to...
(NEO) discovery facility using a one-meter aperture Ground-based Electro-Optical Deep Space Surveillance (GEODSS) telescope
Telescope
A telescope is an instrument that aids in the observation of remote objects by collecting electromagnetic radiation . The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s , using glass lenses...
in 1996. Such wide-field Air Force telescopes were designed for optical observation of Earth orbital spacecraft. The GEODSS instruments used by the LINEAR program are located at the Lincoln Laboratory's experimental test site in the White Sands Missile Range
White Sands Missile Range
White Sands Missile Range is a rocket range of almost in parts of five counties in southern New Mexico. The largest military installation in the United States, WSMR includes the and the WSMR Otera Mesa bombing range...
at Socorro, New Mexico
Socorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
. Data is then sent to the Lincoln Laboratory at Hanscom Air Force Base
Hanscom Air Force Base
Hanscom Air Force Base is a United States Air Force base located approximately south-southwest of Bedford, Massachusetts. The facility is a joint use civil airport/military base with Hanscom Field which provides general aviation and charter service.The host unit at Hanscom is the non-flying...
in Lexington, Massachusetts
Lexington, Massachusetts
Lexington is a town in Middlesex County, Massachusetts, United States. The population was 31,399 at the 2010 census. This town is famous for being the site of the first shot of the American Revolution, in the Battle of Lexington on April 19, 1775.- History :...
.
Between March and July 1997, a 1024 × 1024 charge-coupled device
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...
(CCD) pixel
Pixel
In digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....
detector was used in field tests and, while this CCD detector filled only about one fifth of the telescope's field of view
Field of view
The field of view is the extent of the observable world that is seen at any given moment....
, four near-earth objects were discovered. In October 1997, a large format CCD, of 1960 × 2560 pixels, which covered the telescope's two-square degree
Square degree
A square degree is a non-SI unit measure of solid angle. It is denoted in various ways, including deg2, sq.deg. and ². Just as degrees are used to measure parts of a circle, square degrees are used to measure parts of a sphere. Analogous to one degree being equal to π /180 radians, a...
field of view, was employed successfully to discover a total of nine new near-Earth objects. Five more NEOs were added between November 1997 through January 1998, when both the small and large format CCD detectors were employed.
Beginning in October 1999, a second one-meter telescope was added to the search effort. In 2002, a third telescope of 0.5 meter aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
was brought on-line to provide follow-up observations for the discoveries made by the two 1-meter search telescopes. Currently, LINEAR telescopes observe each patch of sky five times in one evening with most of the efforts going into searching along the ecliptic plane
Ecliptic
The ecliptic is the plane of the earth's orbit around the sun. In more accurate terms, it is the intersection of the celestial sphere with the ecliptic plane, which is the geometric plane containing the mean orbit of the Earth around the Sun...
where most NEOs would be expected. The sensitivity of their CCDs, and particularly their relatively rapid read out rates, allows LINEAR to cover large areas of sky each night. Currently, the LINEAR program is responsible for the majority of NEO discoveries.
The project's principal investigator is Grant Stokes, and co-investigators include Jenifer Evans and Eric Pearce.
In addition to discovering hundreds of thousands of asteroids (225,957 as of December 31, 2007), LINEAR is also credited with the discovery, or co-discovery, or rediscovery of several periodic comets, including 11P/Tempel-Swift-LINEAR
11P/Tempel-Swift-LINEAR
11P/Tempel–Swift–LINEAR is a periodic comet in our solar system.Ernst Wilhelm Leberecht Tempel originally discovered the comet on November 27, 1869, it was later observed by Lewis Swift on October 11, 1880 and realised to be the same comet.After 1908 the comet became an unobservable lost comet,...
, 146P/Shoemaker-LINEAR, 148P/Anderson-LINEAR, 156P/Russell-LINEAR, 158P/Kowal-LINEAR
158P/Kowal-LINEAR
-External links:*...
, 160P/LINEAR
160P/LINEAR
- External links :*...
(LINEAR 43), 165P/LINEAR
165P/LINEAR
- External links :*...
(LINEAR 10), and 176P/LINEAR (LINEAR 52, 118401 LINEAR: one of only five objects classified both as comets and asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
s).
See also
- 2004 FH2004 FH2004 FH is a near-Earth asteroid that was discovered on March 15, 2004, by the NASA-funded LINEAR asteroid survey. The object is roughly 30 metres in diameter and passed just above the Earth's surface on March 18, 2004, at 22:08 UTC; making it the 11th closest approach to Earth recorded...
- List of comets credited to LINEARComet LINEARThe following is a list of comets discovered, co-discovered and re-discovered by the Lincoln Laboratory Near-Earth Asteroid Research project , an Earth-based automated sky survey....
- Planetary Data SystemPlanetary Data SystemThe Planetary Data System is a distributed data system that NASA uses to archive data collected by Solar System robotic missions and ground-based support data associated with those missions. PDS is managed by NASA Headquarters' Planetary Sciences Division. The PDS is an active archive that makes...
(PDS) - Minor Planet CenterMinor Planet CenterThe Minor Planet Center operates at the Smithsonian Astrophysical Observatory , which is part of the Center for Astrophysics along with the Harvard College Observatory ....
- Near Earth Asteroid TrackingNear Earth Asteroid TrackingNear-Earth Asteroid Tracking is a program run by NASA and Jet Propulsion Laboratory to discover near-Earth objects. The NEAT project began in December 1995 and ran until April 2007.-History:...
(NEAT) - Lowell Observatory Near-Earth-Object SearchLowell Observatory Near-Earth-Object SearchLowell Observatory Near-Earth-Object Search ' was a project designed to discover asteroids and comets that orbit near the Earth. The project, funded by NASA, was directed by Dr. Ted Bowell of Lowell Observatory in Flagstaff, Arizona...
(LONEOS) - Pan-STARRSPan-STARRSThe Panoramic Survey Telescope and Rapid Response System is a planned array of astronomical cameras and telescopes and computing facility that will survey the sky on a continual basis, including accurate astrometry and photometry of detected objects...
- SpaceguardSpaceguardThe term Spaceguard loosely refers to a number of efforts to discover and study near-Earth objects . Asteroids are discovered by telescopes which repeatedly survey large areas of sky. Efforts which concentrate on discovering NEOs are considered part of the "Spaceguard Survey," regardless of which...
- SpacewatchSpacewatchSpacewatch is a project at the University of Arizona led by Robert S. McMillan that specializes in the study of minor planets, including various types of asteroids and comets...
External links
- MIT Lincoln Laboratory: LINEAR
- NEO discovery statistics from JPL. Shows the number of asteroids of various types (potentially hazardous, size >1 km, etc.) that different programs have discovered, by year.