 Orbits ofGNU (blue), theinner planets andJupiter (outermost) | |
| Discovery[1] | |
|---|---|
| Discovered by | Spacewatch |
| Discovery site | Kitt Peak National Obs. |
| Discovery date | 5 March 1992 |
| Designations | |
| (9965) GNU | |
Named after | GNU Project[1] (free software project) |
| 1992 EF2 · 1988 BD4 1993 QR3 | |
| main-belt[1][2] · (inner) background[3] | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 30.17yr (11,019 d) |
| Aphelion | 2.8283AU |
| Perihelion | 2.0080 AU |
| 2.4181 AU | |
| Eccentricity | 0.1696 |
| 3.76 yr (1,373 d) | |
| 276.39° | |
| 0° 15m 43.56s / day | |
| Inclination | 12.206° |
| 156.48° | |
| 82.938° | |
| Physical characteristics | |
| 2.07±0.53 km[4] 4.10 km(calculated)[5] 6.22±2.14 km[6] 6.293±0.159 km[7][8] | |
| 39.720±0.1589 h(R)[9] 39.745±0.1589 h(S)[9] | |
| 0.102±0.014[7] 0.1022±0.0145[8] 0.105±0.125[6] 0.20(assumed)[5] 0.53±0.12[4] | |
| D(Pan-STARRS)[10] S(SDSS-MOC)[11] S(assumed)[5] | |
| 14.10[6][8] 14.3[2][5] 14.31±0.14[10] 14.398±0.005(R)[9] 14.72[4] 14.966±0.011(S)[9] | |
9965 GNU, provisional designation1992 EF2, is a backgroundasteroid from the inner regions of theasteroid belt, approximately 4 kilometers (2 miles) in diameter. It was discovered on 5 March 1992, by astronomer of theSpacewatch program at theKitt Peak National Observatory in Arizona, United States.[1] The uncertainD-type asteroid has a longrotation period of 39.7 hours.[5] It was named for the free-softwareGNU Project.[1]
GNU is a non-family asteroid from the main belt'sbackground population.[3]
It orbits the Sun in theinner asteroid belt at a distance of 2.0–2.8 AU once every 3 years and 9 months (1,373 days;semi-major axis of 2.42 AU). Its orbit has aneccentricity of 0.17 and aninclination of 12° with respect to theecliptic.[2] The body'sobservation arc begins with its first observation as1988 BD4 atLa Silla Observatory in January 1988, or 4 years prior to its official discovery observation at Kitt Peak.[1]
GNU has been characterized as a darkD-type asteroid byPan-STARRS' survey and in theSDSS-based taxonomy.[10][11] It is also an assumedS-type asteroid, the most common type in the inner asteroid belt.[5]
In September and October 2012, two rotationallightcurves ofGNU were obtained fromphotometric observations by astronomers at thePalomar Transient Factory in California. Lightcurve analysis gave arotation period of 39.720 and 39.745 hours, with a brightness amplitude of 0.36 and 0.42magnitude in the R- and S-band, respectively (U=2/2).[9] While not being aslow rotator,GNU' period is significantly longer than the average spin rate of 2 to 20 hours, seen among the majority of asteroids.
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,GNU measures between 2.07 and 6.293 kilometers in diameter and its surface has analbedo between 0.102 and 0.53.[4][6][7][8] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and calculates a diameter of 4.10 kilometers based on anabsolute magnitude of 14.3.[5]
Thisminor planet was named for the free-softwareGNU Project, created byRichard Stallman 1984. GNU is therecursive acronym for "GNU is not Unix". The collaborative projects enables programmers to trade and improve uponfree software.[1] The official naming citation was published by theMinor Planet Center on 11 November 2000 (M.P.C. 41571).[12]
