4435 Holt, provisional designation 1983 AG2, is a stony asteroid, sizable Mars-crosser and binary system from the inner regions of the asteroid belt, approximately 5 kilometers in diameter. It was discovered on 13 January 1983, by American astronomer Carolyn Shoemaker at the Palomar Observatory in California, United States.[3] It was later named after American astronomer Henry E. Holt.[2] The discovery of its companion was announced in January 2018.
| Discovery [1] | |
|---|---|
| Discovered by | C. Shoemaker |
| Discovery site | Palomar Obs. |
| Discovery date | 13 January 1983 |
| Designations | |
| (4435) Holt | |
| Pronunciation | ⫽ˈhoʊlt⫽ |
Named after | Henry E. Holt (American astronomer)[2] |
| 1983 AG2 · 1978 PZ2 | |
| Mars-crosser [1][3][4] | |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 37.89 yr (13,840 days) |
| Aphelion | 3.0939 AU |
| Perihelion | 1.5405 AU |
| 2.3172 AU | |
| Eccentricity | 0.3352 |
| 3.53 yr (1,288 days) | |
| 319.21° | |
| 0° 16m 45.84s / day | |
| Inclination | 21.905° |
| 330.93° | |
| 110.08° | |
| Known satellites | 1 |
| Physical characteristics | |
| 5.03±1.17km[5] 6.44 km (derived)[4] | |
| 2.8670±0.0002 h[4] | |
| 0.20 (assumed)[4] 0.28±0.15km[5] | |
| SMASS = S [1][4] | |
| 13.1[1] · 13.32±0.11[6][7] | |
Holt orbits the Sun in the inner main-belt at a distance of 1.5–3.1 AU once every 3 years and 6 months (1,288 days). Its orbit has an eccentricity of 0.34 and an inclination of 22° with respect to the ecliptic.[1] The first precovery was taken at Crimea-Nauchnij in 1978, extending the asteroid's observation arc by 5 years prior to its discovery.[3]
This minor planet was named for American planetary geologist and astronomer Henry E. Holt (born 1929), at NAU and USGS, who has explored the surface of the Moon, its geology and photometric properties during the Apollo and Surveyor programs.[2]
After his retirement, Holt was a principal participant in the Palomar Asteroid and Comet Survey (PACS) from 1983 to 1993.[8] Holt has discovered and co-discovered six comets and 683 minor planets between 1989 and 1993,[9] including 4581 Asclepius,[10] a potentially hazardous asteroid that has made the closest approach to Earth of all numbered asteroids.[2] The official naming citation was published by the Minor Planet Center on 30 January 1991 (M.P.C. 17656).[11]
In the SMASS classification, Holt is a common S-type asteroid.[1]
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Holt measures 5.03 kilometers in diameter and its surface has an albedo of 0.28,[5] while the Collaborative Asteroid Lightcurve Linkassumes a standard albedo for stony asteroids of 0.20 and derives a diameter of 6.44 kilometer with an absolute magnitude of 13.32.[4][6][7]
In November 2017, a rotational lightcurveofHolt was obtained from photometric observation by Robert Stephens and collaborators. Lightcurve analysis gave a rotation periodof2.8670±0.0002 hours with a brightness variation of 0.15 magnitude.[4] During the observations, the presence of an approximately 2-kilometer sized minor-planet moon was detected. The satellite orbits its primary every 42.6 hours (1.777 d).
