Discovery [1] | |
---|---|
Discovered by | T. Kobayashi |
Discovery site | Ōizumi Obs. |
Discovery date | 4 March 1997 |
Designations | |
(7803) Adachi | |
Named after | Makoto Adachi [1] (amateur astronomer) |
1997 EW2 · 1973 AA3 1976 UY17 · 1978 EM1 1992 CF2 | |
main-belt [1][2] · (middle) Agnia [3] | |
Orbital characteristics [2] | |
Epoch 23 March 2018 (JD 2458200.5) | |
Uncertainty parameter 0 | |
Observation arc | 63.96 yr (23,363 d) |
Aphelion | 2.9253 AU |
Perihelion | 2.6459 AU |
2.7856 AU | |
Eccentricity | 0.0502 |
4.65 yr (1,698 d) | |
239.11° | |
0° 12m 43.2s / day | |
Inclination | 4.9969° |
110.63° | |
8.8759° | |
Physical characteristics | |
Dimensions | 6.359±0.129 km[4][5] 10.31 km (calculated)[6] |
5.1966±0.0082 h[7] | |
0.057 (assumed)[6] 0.251±0.055[4][5] | |
S [8] · C (generic)[6] | |
13.1[4] · 13.212±0.005 (R)[7] · 13.3[2] · 13.65±0.27[8] · 13.66[6] | |
7803 Adachi, provisional designation 1997 EW2, is a stony Agnia asteroid from the middle region of the asteroid belt, approximately 6.4 kilometers (4 miles) in diameter. The asteroid was discovered on 4 March 1997, by Japanese amateur astronomer Takao Kobayashi at the Ōizumi Observatory in central Japan. It was named for Japanese amateur astronomer Makoto Adachi.[1] The S-type asteroid has a rotation period of 5.2 hours.[6]
Orbit and classification
Adachi is a member of the Agnia family (514),[3][9] a very large family of stony asteroids with more than 2000 known members.[10] They most likely formed from the breakup of a basalt object, which in turn was spawned from a larger parent body that underwent igneous differentiation.[9] The family's parent body and namesake is the asteroid 847 Agnia.[10]
It orbits the Sun in the central asteroid belt at a distance of 2.6–2.9 AU once every 4 years and 8 months (1,698 days; semi-major axis of 2.79 AU). Its orbit has an eccentricity of 0.05 and an inclination of 5° with respect to the ecliptic.[2] The first precovery was taken at the U.S. Palomar Observatory in 1953, extending the asteroid's observation arc by 44 years prior to it discovery.[1]
Physical characteristics
Adachi has been characterized as a stony S-type asteroid by Pan-STARRS photometric survey,[8] which agrees with the Agnia family's overall spectral type.[10] : 23
Diameter and albedo
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Adachi measures 6.359 kilometers in diameter and its surface has an albedo between 0.251 and 0.2513.[4][5] The Collaborative Asteroid Lightcurve Link assumes a generic, carbonaceous albedo of 0.057 for all minor planets with a semi-major axis of more than 2.7 AU, and consequently calculates a larger diameter of 10.31 kilometers using an absolute magnitude of 13.66.[6]
Rotation period
In August 2013, a rotational lightcurve of Adachi was obtained through photometric observations at the Palomar Transient Factory in California. It showed a period of 5.1966 hours with a brightness variation of 0.31 magnitude (U=2).[7]
Naming
This minor planet was named after Makoto Adachi (born 1953), Japanese amateur astronomer and elementary school teacher from Kyoto. He is the director of the Oriental Astronomical Association and a long-time direct observer of the Solar System's planets, especially Jupiter.[1] The approved naming citation was published by the Minor Planet Center on 6 August 2003 (M.P.C. 49279).[11]
References
- 1 2 3 4 5 6 "7803 Adachi (1997 EW2)". Minor Planet Center. Retrieved 28 April 2016.
- 1 2 3 4 "JPL Small-Body Database Browser: 7803 Adachi (1997 EW2)" (2017-09-27 last obs.). Jet Propulsion Laboratory. Retrieved 8 March 2018.
- 1 2 "Asteroid 7803 Adachi – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 27 October 2019.
- 1 2 3 4 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.
- 1 2 3 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.
- 1 2 3 4 5 6 "LCDB Data for (7803) Adachi". Asteroid Lightcurve Database (LCDB). Retrieved 28 April 2016.
- 1 2 3 Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75.
- 1 2 3 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.
- 1 2 Sunshine, Jessica M.; Bus, Schelte J.; McCoy, Timothy J.; Burbine, Thomas H.; Corrigan, Catherine M.; Binzel, Richard P. (August 2004). "High-calcium pyroxene as an indicator of igneous differentiation in asteroids and meteorites". Meteoritics and Planetary Science. 39 (8): 1343–1357. Bibcode:2004M&PS...39.1343S. doi:10.1111/j.1945-5100.2004.tb00950.x. Retrieved 8 March 2018.
- 1 2 3 Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families". Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 28 April 2016.
External links
- 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
- 7803 Adachi at AstDyS-2, Asteroids—Dynamic Site
- 7803 Adachi at the JPL Small-Body Database