132524 APL,

provisional designation Provisional designation in astronomy is the naming convention applied to astronomical objects immediately following their discovery. The provisional designation is usually superseded by a permanent designation once a reliable orbit has been calcu ...

, is a small

background asteroid An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. An a ...

in the intermediate

asteroid belt The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called ...

. It was discovered by

Lincoln Near-Earth Asteroid Research The Lincoln Near-Earth Asteroid Research (LINEAR) project is a collaboration of the United States Air Force, NASA, and the Massachusetts Institute of Technology's Lincoln Laboratory for the systematic detection and tracking of near-Earth objects ...

in May 2002, and imaged by the ''

New Horizons ''New Horizons'' is an Interplanetary spaceflight, interplanetary space probe that was launched as a part of NASA's New Frontiers program. Engineered by the Johns Hopkins University Applied Physics Laboratory (APL) and the Southwest Research ...

'' space probe on its flyby in June 2006, when it was passing through the asteroid belt. The stony

S-type asteroid S-type asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are of this type, making it the second ...

measures approximately in diameter.

Discovery and classification

''APL'' was discovered on 9 May 2002 by astronomers of the

at the

Lincoln Laboratory Experimental Test Site The MIT Lincoln Laboratory, located in Lexington, Massachusetts, is a United States Department of Defense federally funded research and development center chartered to apply advanced technology to problems of national security. Research and dev ...

near

Socorro, New Mexico Socorro (, '' sə-KOR-oh'') is a city in Socorro County in the U.S. state of New Mexico. It is in the Rio Grande Valley at an elevation of . In 2010 the population was 9,051. It is the county seat of Socorro County. Socorro is located south of A ...

, United States. It is a non-

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

asteroid from the main belt's background population, and orbits the Sun in the

central Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

asteroid belt at a distance of once every 4 years and 2 months (1,534 days;

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...

of ). Its orbit has an

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-center, in geometry * Eccentricity (graph theory) of a v ...

of 0.27 and an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of with respect to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic again ...

Naming

Alan Stern Sol Alan Stern (born November 22, 1957) is an American engineer and planetary scientist. He is the principal investigator of the ''New Horizons'' mission to Pluto and the Chief Scientist at Moon Express. Stern has been involved in 24 suborbital ...

, principal investigator for ''New Horizons'', named the asteroid in reference to the

Johns Hopkins University Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...

Applied Physics Laboratory The Johns Hopkins University Applied Physics Laboratory (Applied Physics Laboratory, or APL) is a not-for-profit University Affiliated Research Center, university-affiliated research center (UARC) in Howard County, Maryland. It is affiliated w ...

(APL), which developed the ''New Horizons'', ''

NEAR Shoemaker ''Near Earth Asteroid Rendezvous – Shoemaker'' (''NEAR Shoemaker''), renamed after its 1996 launch in honor of planetary scientist Eugene Shoemaker, was a robotic space probe designed by the Johns Hopkins University Applied Physics Laborator ...

'' and ''

MESSENGER ''MESSENGER'' was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury's chemical composition, geology, and magnetic field. The name is a backronym for "Mercury Surface, Space Environment, Geoche ...

'' missions. The official naming citation was published 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 ...

on 6 January 2007 ().

''New Horizons'' fly by

The ''

'' probe flew by it at a distance of approximately on 13 June 2006. At its closest, it was about of a lunar distance away from the asteroid. The flyby was incidental, and not all the instruments were online at this time; they were still being activated after the spacecraft's launch on January 19, 2006. This is why the spacecraft's reconnaissance imager and highest magnification telescope were not online yet at the time of the flyby.

Ralph instrument

''APL'' was imaged with the 75-millimeter Ralph telescope, but not with the designed reconnaissance imager Long Range Reconnaissance Imager (

LORRI Lorri may refer to: Acronym * LORRI, the Long Range Reconnaissance Imager, a camera on board the ''New Horizons'' spacecraft Given name * Lorri Bagley, an American actress and model * Lorri Jean, a leader in the gay, lesbian, bisexual and transg ...

) because it was not turned on yet. LORRI was not activated until 29 August 2006 when its cover was opened and its first light image would be

Messier 7 Messier 7 or M7, also designated NGC 6475 and sometimes known as the Ptolemy Cluster, is an open cluster of stars in the constellation of Scorpius. The cluster is easily detectable with the naked eye, close to the "stinger" of Scorpius. With a d ...

. It was, in general, possible to capitalize on the target of opportunity, and the asteroid was tracked for several days in June 2006 in addition to the other tests. In March, ''New Horizons'' had passed the orbit of Mars, and the spacecraft was undergoing various course correction maneuvers and tests throughout this time; as mentioned LORRI was not activated for another couple months. ''New Horizons'' passed through the asteroid belt during the summer of 2006, and the test helped prepare the team and spacecraft for the future flybys of Jupiter and Pluto. The

is a feature of the Solar System, consisting of a large number asteroids that orbit the sun primarily between (Earth-Sun distance) which is between the orbits of planets

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...

and

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...

Traversing the asteroid belt

Crossing the asteroid belt is possible, because although there are over a million asteroids larger than in diameter, the distance between them is so large spacecraft pass through empty space. This was established in the early 1970s when '' Pioneer 10'' and '' Pioneer 11'' traversed the belt for the first time. There is some increased probability of encountering dust, but otherwise it takes special planning to actually pass very close to an asteroid, as was done with ''

Galileo Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He was ...

''. In the 1990s, when it passed through the belt on its way to its second Earth

gravity assist In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement (e.g. orbit around the Sun) and gravity of a planet or other astronomical object to alter the p ...

, it flew by

951 Gaspra 951 Gaspra is an S-type asteroid that orbits very close to the inner edge of the asteroid belt. Gaspra was discovered by Russian astronomer G. N. Neujmin in 1916. Neujmin named it after Gaspra, a Black Sea retreat that was visited by his contemp ...

; after the flyby en route to Jupiter, it flew by

243 Ida Ida, minor planet designation 243 Ida, is an asteroid in the Koronis family of the asteroid belt. It was discovered on 29 September 1884 by Austrian astronomer Johann Palisa at Vienna Observatory and named after a nymph from Greek mythology. ...

and discovered its moon

Dactyl Dactyl may refer to: * Dactyl (mythology), a legendary being * Dactyl (poetry), a metrical unit of verse * Dactyl Foundation, an arts organization * Finger, a part of the hand * Dactylus, part of a decapod crustacean * "-dactyl", a suffix used ...

Physical characteristics

Prior and in support of the ''New Horizons'' fly by on 13 June 2006, astronomers at

European Southern Observatory The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental organization, intergovernmental research organisation made up of 16 mem ...

Paranal Observatory Paranal Observatory is an astronomical observatory operated by the European Southern Observatory (ESO). It is located in the Atacama Desert of northern Chile on Cerro Paranal at altitude, south of Antofagasta. By total light-collecting area, it ...

were observing ''APL'' with one of the four 8.2-meter

Very Large Telescope The Very Large Telescope (VLT) is a telescope facility operated by the European Southern Observatory on Cerro Paranal in the Atacama Desert of northern Chile. It consists of four individual telescopes, each with a primary mirror 8.2 m across, ...

s (UT1, ''Antu'') between 25 May and 2 June 2006. The astronomers found that ''APL'' has a

spectral type In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

of a common, stony

. Using the Ralph instrument, ''New Horizons'' was later able to estimate a diameter of approximately for the asteroid.

References

External links

Discovery Circumstances: Numbered Minor Planets
* * {{DEFAULTSORT:APL 132524 132524 Named minor planets New Horizons 132524 20060613 20020509