The Spacewatch Project is an

astronomical survey An astronomical survey is a general map or image of a region of the sky (or of the whole sky) that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of images, spectra, or other observations of ob ...

that specializes in the study of

minor planet According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term '' ...

s, including various types of

asteroid An asteroid is a minor planet of the Solar System#Inner solar system, inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic o ...

s and

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or Coma (cometary), coma, and sometimes also a Comet ta ...

s at

University of Arizona The University of Arizona (Arizona, U of A, UArizona, or UA) is a public land-grant research university in Tucson, Arizona. Founded in 1885 by the 13th Arizona Territorial Legislature, it was the first university in the Arizona Territory. ...

telescopes on Kitt Peak near Tucson, Arizona, in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

. The Spacewatch Project has been active longer than any other similar currently active programs. Spacewatch was founded in 1980 by

Tom Gehrels Anton M.J. "Tom" Gehrels (February 21, 1925 – July 11, 2011) was a Dutch–American astronomer, Professor of Planetary Sciences, and Astronomer at the University of Arizona, Tucson. Biography Youth and education Gehrels was born at Haa ...

and Robert S. McMillan, and is currently led by astronomer Melissa Brucker at the

. Spacewatch uses several telescopes on Kitt Peak for follow-up observations of

near-Earth object A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU) ...

s. The Spacewatch Project uses three telescopes of apertures 0.9-m, 1.8-m, and 2.3-m. These telescopes are located on Kitt Peak mountain in Arizona, and the first two are dedicated to the purpose of locating Near-Earth Objects (NEOs). The 36 inch (0.9 meter) telescope on Kitt Peak has been in use by Spacewatch since 1984, and since 2000 the 72 inch (1.8 meter) Spacewatch telescope. The 36 inch telescope continued in use and was further upgraded, in particular the telescopes use electronic detectors. Spacewatch's 1.8-meter telescope is the largest in the world that is used exclusively for asteroids and comets. It can find asteroids and comets anywhere from the space near Earth to regions beyond the orbit of Neptune and to do astrometry on the fainter of objects that are already known. The telescope is pointed on stars and tracked with a real time video-rate camera at folded prime focus. Spacewatch was the first to use CCDs to survey the sky for comets and asteroids. When added, they permitted faster coverage of the sky than the pre-2002 system. Each year, Spacewatch observes approximately 35 radar targets, 50 near-Earth objects, and 100 potential spacecraft rendezvous destinations. From 2013 to 2016, Spacewatch observed half of all NEOs and

potentially hazardous asteroid A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an orbit that can make close approaches to the Earth and is large enough to cause significant regional damage in the event of impact. They are ...

s (PHAs) observed by anyone in that time. , Spacewatch had discovered over 179,000 minor planets numbered by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

History

The 1.8 meter Spacewatch telescope and its building on Kitt Peak were dedicated on June 7, 1997 for the purpose of finding previously unknown asteroids and comets. Since January 1 2003, Spacewatch has made ~2400 separate-night detections of Near-Earth Objects. There was an upgrade to the 0.9 meter which was funded by

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedi ...

and the Kirsch Foundation. The Spacewatch Project is the longest-running of all present programs of astrometry of solar system objects.

Spacewatch in Action

Spacewatch conducted a survey that was proposed May 12, 2006, and accepted on November 13, 2006. This survey used data taken over 34 months by the

’s Spacewatch Project based at

Steward Observatory Steward Observatory is the research arm of the Department of Astronomy at the University of Arizona (UArizona). Its offices are located on the UArizona campus in Tucson, Arizona (US). Established in 1916, the first telescope and building were f ...

, Kitt Peak. Spacewatch revisited the same sky area every three to seven nights in order to track cohorts of main-belt asteroids. This survey discovered one new large

Kuiper Belt The Kuiper belt () is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune at 30 astronomical units (AU) to approximately 50 AU from the Sun. It is similar to the asteroid belt, but is far larger—20 t ...

Object (KBO) and detected six others. This proved that new sweeps of the sky are productive even if they have been previously examined simply due to the complexities of running large surveys over many nights and variable conditions.

Notable discoveries

* Callirrhoe *

5145 Pholus 5145 Pholus is an eccentric centaur in the outer Solar System, approximately in diameter, that crosses the orbit of both Saturn and Neptune. It was discovered on 9 January 1992 by American astronomer David Rabinowitz (uncredited) of UA's Space ...

* 9965 GNU * 9885 Linux *

9882 Stallman Year 988 ( CMLXXXVIII) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar. Events By place Byzantine Empire * Fall – Emperor Basil II, supported by a contingent of 6,000 Varangian ...

* 9793 Torvalds *

20000 Varuna 20000 Varuna, provisional designation , is a large trans-Neptunian object in the Kuiper belt. It was discovered in November 2000 by American astronomer Robert McMillan during a Spacewatch survey at the Kitt Peak National Observatory. It is na ...

60558 Echeclus 60558 Echeclus is a centaur, approximately in diameter, located in the outer Solar System. It was discovered by Spacewatch in 2000 and initially classified as a minor planet with provisional designation (also written 2000 EC98). Research in ...

* , target of

JAXA The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into o ...

Hayabusa2 is an asteroid sample-return mission operated by the Japanese state space agency JAXA. It is a successor to the ''Hayabusa'' mission, which returned asteroid samples for the first time in June 2010. ''Hayabusa2'' was launched on 3 December ...

extended mission. *

65803 Didymos 65803 Didymos (provisional designation ) is a sub-kilometer asteroid and binary system that is classified as a potentially hazardous asteroid and near-Earth object of the Apollo group. The asteroid was discovered in 1996 by the Spacewatch surv ...

, target of the

DART Dart or DART may refer to: * Dart, the equipment in the game of darts Arts, entertainment and media * Dart (comics), an Image Comics superhero * Dart, a character from ''G.I. Joe'' * Dart, a ''Thomas & Friends'' railway engine character * D ...

mission * * *

(136617) 1994 CC is a sub-kilometer trinary asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group. Discovery was discovered by Spacewatch's Jim Scotti at Kitt Peak National Observatory on 3 February 1994. In June ...

* C/1992 J1 * 125P/Spacewatch *

174567 Varda 174567 Varda (provisional designation ) is a binary trans-Neptunian planetoid of the resonant hot classical population of the Kuiper belt, located in the outermost region of the Solar System. Its moon, Ilmarë, was discovered in 2009. Michael ...

* * The project rediscovered 719 Albert, a long- lost asteroid.

References

Planetary science Astronomical discoveries by institution * Near-Earth object tracking {{Observatory-stub

History

Spacewatch in Action

Notable discoveries

See also

References