Astronomy:(136617) 1994 CC
 | |
| Discovery[1] | |
|---|---|
| Discovered by | Spacewatch |
| Discovery site | Kitt Peak National Obs. |
| Discovery date | 3 February 1994 |
| Designations | |
| (136617) 1994 CC | |
| 1994 CC | |
| Minor planet category | NEO · PHA · Apollo[1][2] Earth-crosser |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 28.45 yr (10,391 days) |
| |{{{apsis}}}|helion}} | 2.3206 AU |
| |{{{apsis}}}|helion}} | 0.9551 AU |
| 1.6378 AU | |
| Eccentricity | 0.4169 |
| Orbital period | 2.10 yr (766 days) |
| Mean anomaly | 321.07° |
| Mean motion | 0° 28m 12.72s / day |
| Inclination | 4.6806° |
| Longitude of ascending node | 268.55° |
| 24.842° | |
| Known satellites | 2[3] |
| Earth MOID | 0.0157 AU · 6.1 LD |
| Physical characteristics | |
| Mean diameter | 0.62±0.06 km[4] 0.650 km[3] |
| Rotation period | 2.3886±0.0001 h[3] 2.38860±0.00009 h[4] |
| Geometric albedo | 0.3821 (derived)[5] |
| Sq[4] · Sa[6] · S[5][7] | |
| Absolute magnitude (H) | 17.00[7] · 17.7[1][5] · 18.12±0.84[8] |
(136617) 1994 CC is a sub-kilometer trinary[3] asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group.
Discovery
1994 CC was discovered by Spacewatch's Jim Scotti at Kitt Peak National Observatory on 3 February 1994.[2] In June 2009 it was shown to be a triple system, i.e. the largest body is orbited by two satellites; only about one percent (1%) of near-Earth asteroids observed by a radar are found to be triple systems such as this one.[9] The only other unambiguously identified triple asteroids in the near-Earth population are (153591) 2001 SN263, which was discovered to be a triple system in 2008, and 3122 Florence, which was found to be a triple system in 2017.
Observations
A team of NASA's Jet Propulsion Laboratory (JPL) (Pasadena, California) scientists led by Marina Brozovic and Lance Benner, made the discovery using radar imaging at NASA's Goldstone Solar System Radar on June 12 and June 14, 2009. They showed that the near-Earth asteroid 1994 CC is a triple system, which encountered Earth within 2.52 million kilometers on June 10, 2009. This relatively close approach to Earth made the discovery possible, as before the approach, scientists knew very little about this asteroid. In fact, 1994 CC is only the second triple system known in the near-Earth objects population.[9]
1994 CC consists of a central object about 700 meters in diameter that has two moons revolving around it. Scientists' preliminary analysis of the system suggests that the moons are at least 50 meters in diameter. In a similar study, the radar observations at Arecibo Observatory in Puerto Rico, led by the Mike Nolan, also confirmed the detection of all three objects. The scientists plan to use the combined observations from the Goldstone and Arecibo observatories to study 1994 CC's orbital and physical properties further.[9]
The next similar Earth flyby for the asteroid 1994 CC will happen in 2074 when the triple system is projected to fly past Earth at a distance of 2.5 million kilometers.[9]
Orbital characteristics of satellites
The orbital properties of the satellites are listed in this table.[10] The orbital planes of both satellites are inclined relative to each other, by approximately 16°. Such a large inclination is suggestive of past evolutionary events (e.g. close encounter with a terrestrial planet, mean-motion resonance crossing) that may have excited their orbits from a coplanar configuration to an inclined state.
| Name | Mass [109 kg] |
Semi-major axis [km] |
Orbital period [days] |
Eccentricity | Inclination (relative to asteroid) [°] |
|---|---|---|---|---|---|
| Beta | ~6 | 1.7 | 1.243 | 0.002 | 95 |
| Gamma | ~1 | 6.1 | 8.376 | 0.192 | 79 |
Numbering and naming
This minor planet was numbered by the Minor Planet Center on 5 December 2006.[11] (As of 2019), it has not been named.[2]
See also
References
- ↑ 1.0 1.1 1.2 1.3 "JPL Small-Body Database Browser: 136617 (1994 CC)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2136617.
- ↑ 2.0 2.1 2.2 "136617 (1994 CC)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=136617.
- ↑ 3.0 3.1 3.2 3.3 Brozovic, M.; Benner, L. A. M.; Nolan, M. C. (June 2009). "(136617) 1994 CC". IAU Circ. (9053). Bibcode: 2009IAUC.9053....2B. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2009IAUC.9053....2B. Retrieved 22 March 2017.
- ↑ 4.0 4.1 4.2 Brozovic, Marina; Benner, Lance A. M.; Taylor, Patrick A.; Nolan, Michael C. (November 2011). "Radar and optical observations and physical modeling of triple near-Earth Asteroid (136617) 1994 CC". Icarus 216 (1): 241–256. doi:10.1016/j.icarus.2011.09.002. Bibcode: 2011Icar..216..241B. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011Icar..216..241B. Retrieved 22 March 2017.
- ↑ 5.0 5.1 5.2 "LCDB Data for (136617)". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=136617%7C.
- ↑ Thomas, Cristina A.; Emery, Joshua P.; Trilling, David E.; Delbó, Marco; Hora, Joseph L.; Mueller, Michael (January 2014). "Physical characterization of Warm Spitzer-observed near-Earth objects". Icarus 228: 217–246. doi:10.1016/j.icarus.2013.10.004. Bibcode: 2014Icar..228..217T. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014Icar..228..217T. Retrieved 22 March 2017.
- ↑ 7.0 7.1 Carry, B.; Solano, E.; Eggl, S.; DeMeo, F. E. (April 2016). "Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry". Icarus 268: 340–354. doi:10.1016/j.icarus.2015.12.047. Bibcode: 2016Icar..268..340C. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2016Icar..268..340C. Retrieved 22 March 2017.
- ↑ 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. doi:10.1016/j.icarus.2015.08.007. Bibcode: 2015Icar..261...34V. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V. Retrieved 22 March 2017.
- ↑ 9.0 9.1 9.2 9.3 "Triple Asteroid System Triples Observers' Interest". NASA. 6 August 2009. http://www.nasa.gov/topics/solarsystem/features/neo20090806.html. "Radar imaging at NASA's Goldstone Solar System Radar [..] revealed that near-Earth asteroid 1994 CC is a triple system"
- ↑ Fang, Julia (May 2011). "Orbits of Near-Earth Asteroid Triples 2001 SN263 and 1994 CC: Properties, Origin, and Evolution". Astronomical Journal 131 (5): 154. doi:10.1088/0004-6256/141/5/154. Bibcode: 2011AJ....141..154F.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html.
External links
- Spacewatch Discoveries for 1994, Spacewatch NEO Detections by Year, University of Arizona
- Official press release by NASA on triplet system
- (136617) 1994 CC compiled by Wm. Robert Johnston
- Julia Fang, "Orbits of Near-Earth Asteroid Triples 2001 SN263 and 1994 CC: Properties, Origin, and Evolution", [1]
- (136617) 1994 CC at NeoDyS-2, Near Earth Objects—Dynamic Site
- Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
- (136617) 1994 CC at ESA–space situational awareness
- (136617) 1994 CC at the JPL Small-Body Database
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