9084 Achristou (provisional designation 1995 CS1) is a stony Hungaria asteroid from the innermost regions of the asteroid belt, about 1.9 kilometers in diameter. It was discovered by British astronomer David J. Asher at Siding Spring Observatory in New South Wales, Australia, on 3 February 1995.[8] The asteroid was named after British planetary astronomer Apostolos Christou.[2]
| Discovery [1] | |
|---|---|
| Discovered by | D. J. Asher |
| Discovery site | Siding Spring Obs. |
| Discovery date | 3 February 1995 |
| Designations | |
| (9084) Achristou | |
Named after | Apostolos Christou (British astronomer)[2] |
| 1995 CS1 · 1980 GV1 | |
| main-belt · Hungaria [3] | |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 36.64 yr (13,381 days) |
| Aphelion | 2.0048 AU |
| Perihelion | 1.7145 AU |
| 1.8597 AU | |
| Eccentricity | 0.0780 |
| 2.54 yr (926 days) | |
| 206.11° | |
| 0° 23m 18.96s / day | |
| Inclination | 23.098° |
| 197.54° | |
| 72.116° | |
| Earth MOID | 0.7794 AU |
| Physical characteristics | |
| Dimensions | 1.76 km (calculated)[3] 1.916±0.367 km[4][5] |
| 8.84±0.02 h[6][a] | |
| 0.30 (assumed)[3] 0.333±0.078[4][5] | |
| E [3] | |
| 15.7[1][3] · 15.4[4] · 16.08±0.28[7] | |
Orbit and classification edit
Achristou is a member of the Hungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun at a distance of 1.7–2.0 AU once every 2 years and 6 months (926 days). Its orbit has an eccentricity of 0.08 and an inclination of 23° with respect to the ecliptic.[1] In April 1980, it was first identified as 1980 GV1 at Palomar Observatory, extending the body's observation arc by 15 years prior to its official discovery observation at Siding Spring.[8]
Physical characteristics edit
Achristou has been characterized as a bright E-type asteroid.[3]
Rotation period edit
In May 2013, a rotational lightcurve of Achristou was obtained from photometric observations by American astronomer Robert Stephens at the Center for Solar System Studies (U81) in California. Lightcurve analysis gave a rotation period of 8.84 hours with a low brightness variation of 0.09 magnitude (U=2+).[6][a]
Diameter and albedo edit
Based on the survey carried out by the NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, Achristou measures 1.9 kilometers in diameter and its surface has an albedo of 0.33,[4][5] while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.30 and calculates a diameter of 1.8 kilometers with an absolute magnitude of 15.7.[3]
Naming edit
This minor planet was named after Apostolos Christou (born 1968), planetary astronomer and programmer at the North Irish Armagh Observatory, after which the minor planet 10502 Armaghobs was named. His field or research include minor planets in co-orbit with Venus, designing near-Earth asteroids missions, the dwarf planet 1 Ceres, meteor impacts on Venus, as well as the irregular satellite families of the outer planets.[2] The official naming citation was published by the Minor Planet Center on 23 May 2005 (M.P.C. 54173).[9]
Notes edit
- ^ a b Stephens (2013): lightcurve plot of (9084) Achristou with a rotation period 8.84±0.02 hours with a brightness amplitude of 0.09 mag. Summary figures at Collaborative Asteroid Lightcurve Link (CALL)
References edit
- ^ a b c d "JPL Small-Body Database Browser: 9084 Achristou (1995 CS1)" (2016-11-26 last obs.). Jet Propulsion Laboratory. Retrieved 22 June 2017.
- ^ a b c Schmadel, Lutz D. (2006). "(9084) Achristou [1.86, 0.08, 23.1]". Dictionary of Minor Planet Names – (9084) Achristou, Addendum to Fifth Edition: 2003–2005. Springer Berlin Heidelberg. p. 42. doi:10.1007/978-3-540-34361-5_303. ISBN 978-3-540-34360-8.
- ^ a b c d e f g "LCDB Data for (9084) Achristou". Asteroid Lightcurve Database (LCDB). Retrieved 28 April 2016.
- ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 118700974. Retrieved 28 April 2016.
- ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. S2CID 118745497. Retrieved 4 December 2016.
- ^ a b Stephens, Robert D.; Coley, Daniel; Warner, Brian D. (January 2014). "Collaborative Asteroid Lightcurve Analysis at the Center for Solar System Studies: 2013 April-June". The Minor Planet Bulletin. 41 (1): 8–13. Bibcode:2014MPBu...41....8S. ISSN 1052-8091. Retrieved 28 April 2016.
- ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339. Retrieved 28 April 2016.
- ^ a b "9084 Achristou (1995 CS1)". Minor Planet Center. Retrieved 28 April 2016.
- ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 28 April 2016.
External links edit
- Apostolos Christou, at Armagh Observatory, 7 Nov 2013
- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (5001)-(10000) – Minor Planet Center
- 9084 Achristou at AstDyS-2, Asteroids—Dynamic Site
- 9084 Achristou at the JPL Small-Body Database
