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 ''mino ...

s, including various types of asteroids 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, and sometimes also a tail. These phenomena ...

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. T ...

telescopes on

Kitt Peak Kitt Peak ( ood, Ioligam) is a mountain in the U.S. state of Arizona, and at is the highest point in the Quinlan Mountains. It is the location of the Kitt Peak National Observatory. The radio telescope at the observatory is one of ten dishes co ...

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 states, a federal district, five major unincorporated territorie ...

. 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

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

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

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 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). ...

, 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 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 ''mino ...

numbered by the Minor Planet Center.

History

The 1.8 meter Spacewatch telescope and its building on

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, succeeding t ...

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 ...

. 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 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 Callirrhoe (, grc, Καλλιρρόη; also Callirhoe) may refer to: * Callirhoe (mythology), several figures in Greek mythology, including: ** Callirrhoe (Oceanid), daughter of Oceanus and Tethys ** Callirrhoe (daughter of Achelous) * Callirrhoe ...

* 5145 Pholus *

9965 GNU 9965 GNU, provisional designation , is a background asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered on 5 March 1992, by astronomer of the Spacewatch program at the Kitt Peak National Observatory ...

* 9885 Linux * 9882 Stallman * 9793 Torvalds * 20000 Varuna *

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 2 ...

* , 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 orb ...

's Hayabusa2 extended mission. * 65803 Didymos, 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 * Dar ...

mission * * * (136617) 1994 CC * C/1992 J1 * 125P/Spacewatch * 174567 Varda * * The project rediscovered

719 Albert 719 Albert, provisional designation , is a stony asteroid, approximately 2.5 kilometers in diameter, classified as a near-Earth object of the Amor group of asteroids. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observat ...

, a long-

lost asteroid A minor planet is "lost" when today's observers cannot find it, because its location is too uncertain to target observations. This happens if the orbital elements of a minor planet are not known accurately enough, typically because the observat ...

References

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

History

Spacewatch in Action

Notable discoveries

See also

References