(7352) 1994 CO
Discovery [1] | |
---|---|
Discovered by |
S. Ueda H. Kaneda |
Discovery site | Kushiro Obs. |
Discovery date | 4 February 1994 |
Designations | |
MPC designation | (7352) 1994 CO |
1994 CO · 1991 VD3 | |
Jupiter trojan [1][2] Trojan [3] · background [4] | |
Orbital characteristics [2] | |
Epoch 23 March 2018 (JD 2458200.5) | |
Uncertainty parameter 0 | |
Observation arc | 29.75 yr (10,868 d) |
Aphelion | 5.3239 AU |
Perihelion | 4.9409 AU |
5.1324 AU | |
Eccentricity | 0.0373 |
11.63 yr (4,247 d) | |
257.93° | |
0° 5m 5.28s / day | |
Inclination | 8.1816° |
130.32° | |
125.51° | |
Jupiter MOID | 0.0307 AU |
TJupiter | 2.9790 |
Physical characteristics | |
Mean diameter |
±2.06 km 47.07[5] ±0.79 km 47.73[6] |
±3 h 648[7][lower-alpha 1] | |
±0.023 0.093[6] ±0.020 0.207[5] | |
X/L (SDSS-MOC)[8][9] B–V = ±0.060 0.660[10] V–R = ±0.040 0.460[10] V–I = ±0.027 0.850[11] | |
9.00[5] 9.8[6] 9.9[1][2] | |
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(7352) 1994 CO, provisional designation 1994 CO, is a larger Jupiter trojan from the Trojan camp, approximately 48 kilometers (30 miles) in diameter. The tumbling Jovian asteroid is a slow rotator with an exceptionally long rotation period of 648 hours. It was discovered on 4 February 1994 by Japanese astronomers Seiji Ueda and Hiroshi Kaneda at the Kushiro Observatory on Hokkaidō, Japan,[1] and has not been named since its numbering in December 1996.[12]
Classification and orbit
1994 CO is a Jupiter trojan in a 1:1 orbital resonance with Jupiter. It is located in the trailering Trojan camp at the Gas Giant's L5 Lagrangian point, 60° behind its orbit .[3] It is also a non-family asteroid of the Jovian background population.[4]
It orbits the Sun at a distance of 4.9–5.3 AU once every 11 years and 8 months (4,247 days; semi-major axis of 5.13 AU). Its orbit has an eccentricity of 0.04 and an inclination of 8° with respect to the ecliptic.[2] The body's observation arc begins with a precovery taken at the Palomar Observatory in August 1988, more than 5 years prior to its official discovery observation at Kushiro.[1]
Physical characteristics
In the SDSS-based taxonomy, 1994 CO is classified as an X/L-type.[8][9] This is unusual as most Jupiter trojans are D-types, with the reminder being mostly C- and P-type asteroids. It has a V–I color index of 0.85.[11]
Rotation period
In October 2013, a rotational lightcurve was obtained for this asteroid from photometric observations by American amateur astronomer Robert Stephens at the Trojan Station (U81) of the Center for Solar System Studies in Landers, California. It gave a well-defined, outstandingly long rotation period of ±3 hours with a brightness variation of 0.30 648magnitude (U=3-).[7][lower-alpha 1] As of 2018, there are only about three dozens known slow rotators with periods longer than that of 1994 CO.
Tumbler
The astronomers also detected a non-principal axis rotation seen in distinct rotational cycles in successive order. This is commonly known as tumbling.[7] 1994 CO is the six-largest asteroid and the second-largest Jupiter trojan after 4902 Thessandrus known to be is such a state (also see list of tumblers).[11]
Diameter and albedo
According to the space-based surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, 1994 CO measures 47.07 and 47.73 kilometers in diameter and its surface has an albedo of 0.207 and 0.093, respectively.[5][6] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a larger diameter of 55.67 kilometers, based on an absolute magnitude of 10.0.[11]
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Numbering and naming
This minor planet was numbered by the Minor Planet Center on 24 December 1996 (M.P.C. 28576).[12] As of 2018, it has not been named.[1]
Notes
- 1 2 Lightcurve plots of (7352) 1994 CO from September to Novbember 2013 by Robert Stephens at the Center for Solar System Studies (U81). Quality code is not available (lightcurve rating at CS3). Summary figures at the LCDB and CS3.
References
- 1 2 3 4 5 6 "7352 (1994 CO)". Minor Planet Center. Retrieved 22 June 2018.
- 1 2 3 4 "JPL Small-Body Database Browser: 7352 (1994 CO)" (2018-05-19 last obs.). Jet Propulsion Laboratory. Retrieved 22 June 2018.
- 1 2 "List of Jupiter Trojans". Minor Planet Center. 1 June 2018. Retrieved 22 June 2018.
- 1 2 "Asteroid (7352) 1994 CO – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 22 June 2018.
- 1 2 3 4 Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. Retrieved 22 June 2018. (online, AcuA catalog p. 153)
- 1 2 3 4 Grav, T.; Mainzer, A. K.; Bauer, J. M.; Masiero, J. R.; Nugent, C. R. (November 2012). "WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy". The Astrophysical Journal. 759 (1): 10. arXiv:1209.1549. Bibcode:2012ApJ...759...49G. doi:10.1088/0004-637X/759/1/49. Retrieved 22 June 2018. (online catalog)
- 1 2 3 Stephens, Robert D.; French, Linda M.; Davitt, Chelsea; Coley, Daniel R. (April 2014). "At the Scaean Gates: Observations Jovian Trojan Asteroids, July- December 2013". The Minor Planet Bulletin. 41 (2): 95–100. Bibcode:2014MPBu...41...95S. ISSN 1052-8091. Retrieved 22 June 2018.
- 1 2 Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 22 June 2018.
- 1 2 "Asteroid (7352) 1994 CO". Small Bodies Data Ferret. Retrieved 22 June 2018.
- 1 2 Chatelain, Joseph P.; Henry, Todd J.; French, Linda M.; Winters, Jennifer G.; Trilling, David E. (June 2016). "Photometric colors of the brightest members of the Jupiter L5 Trojan cloud". Icarus. 271: 158–169. Bibcode:2016Icar..271..158C. doi:10.1016/j.icarus.2016.01.026. Retrieved 22 June 2016.
- 1 2 3 4 "LCDB Data for (7352)". Asteroid Lightcurve Database (LCDB). Retrieved 22 June 2018.
- 1 2 "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 22 June 2018.
External links
- Asteroid Lightcurve Database (LCDB), query form (info)
- Discovery Circumstances: Numbered Minor Planets (5001)-(10000) – Minor Planet Center
- (7352) 1994 CO at AstDyS-2, Asteroids—Dynamic Site
- (7352) 1994 CO at the JPL Small-Body Database