(136617) 1994 CC

Near-Earth asteroid September 2020 yes (136617) 1994 CC #FFC2E0 1994CC-with-moons.gif Goldstone animation of 1994 CC orbited by two minor-planet moons in 2009 padding: 5px 0; 3 February 1994 Spacewatch Kitt Peak National Obs. (136617) 1994 CC NEOPHAApolloEarth-crosser 4 September 2017 (JD 2458000.5) 0 28.45 yr (10,391 days) 2.3206 AU 0.9551 AU 1.6378 AU 0.4169 2.10 yr (766 days) 321.07° 0.4702 ms / day 4.6806° 268.55° 24.842° 0.0157 AU6.1 LD 2 0.62 0.06 km0.650 km 2.69 0.329 11 kg (system mass) Wm. Robert Johnston (136617) 1994 CC, "Beta", and "Gamma" Johnston's Archive 21 September 2014 http://www.johnstonsarchive.net/astro/astmoons/am-136617.html 9 June 2019 2.5935 0.1315 11 kg (primary)Fang Julia Orbits of Near-Earth Asteroid Triples 2001 SN263 and 1994 CC: Properties, Origin, and Evolution 2011AJ....141..154F Astronomical Journal 131 5 154 May 2011 10.1088/0004-6256/141/5/154 1012.2154v2 2.1 0.6 g/cm3 (system) 1.98 g/cm3 (primary)9 2.3886 0.0001 h2.38860 0.00009 h 0.3821 (derived)0.42 0.1 SqSaS 17.0017.718.12 0.84 (136617) 1994 CC is a sub-kilometer triple asteroid, classified as a 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. 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. The only other unambiguously identified triple asteroids in the near-Earth population are (153591) 2001 SN 263, which was discovered to be a triple system in 2008, and 3122 Florence, which was found to be a triple system in 2017. Observations thumb|left|Radar images of 1994 CC at two different times with its two moons 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. 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 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. 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. Orbital characteristics of satellites The orbital properties of the satellites are listed in this table. 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 5.8 0.3 0.5 1.729 0.008 1.243 0.0329 0.002 0.015 83.376 11.158 Gamma 0.911 2.0 0.9 6.130 0.108 8.376 0.404 0.192 0.014 71.709 8.994 Numbering and naming This minor planet was numbered by the Minor Planet Center on 5 December 2006. 2019, it has not been named. See also List of exceptional asteroids 2004 FH 87 Sylvia 433 Eros (153591) 2001 SN 263 References 30em 2017-02-25 last obs. JPL Small-Body Database Browser: 136617 (1994 CC) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2136617 Jet Propulsion Laboratory 1 June 2017 136617 (1994 CC) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=136617 22 March 2017 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 24 February 2018 Triple Asteroid System Triples Observers' Interest 6 August 2009 NASA 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 22 March 2017 8 November 2010 https://web.archive.org/web/20101108232812/http://www.nasa.gov/topics/solarsystem/features/neo20090806.html dead 136617 22 March 2017 6 M. Brozovic L. A. M. Benner M. C. Nolan E. S. Howell Ellen Howell C. Magri J. D. Giorgini P. A. Taylor J. L. Margot M. W. Busch M. K. Shepard L. M. Carter J. S. Jao J. van Brimmer C. R. Franck M. A. Silva M. A. Kodis D. T. Kelley M. A. Slade A. Bramson K. J. Lawrence J. T. Pollock P. Pravec D. E. Reichart K. M. Ivarsen J. Haislip M. C. Nysewander A. P. Lacluyze June 2009 (136617) 1994 CC http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2009IAUC.9053....2B IAU Circ. 9053 2009IAUC.9053....2B 22 March 2017 6 Marina Brozovic Lance A. M. Benner Patrick A. Taylor Michael C. Nolan Ellen S. Howell Ellen Howell Christopher Magri Daniel J. Scheeres Jon D. Giorgini Joseph T. Pollock Petr Pravec Adrián Galád Julia Fang Jean-Luc Margot Michael W. Busch Michael K. Shepard Daniel E. Reichart Kevin M. Ivarsen Joshua B. Haislip Aaron P. LaCluyze Joseph Jao Martin A. Slade Kenneth J. Lawrence Michael D. Hicks November 2011 Radar and optical observations and physical modeling of triple near-Earth Asteroid (136617) 1994 CC http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011Icar..216..241B Icarus 216 1 241–256 2011Icar..216..241B 10.1016/j.icarus.2011.09.002 1310.2000 22 March 2017 Cristina A. Thomas Joshua P. Emery David E. Trilling Marco Delbó Joseph L. Hora Michael Mueller January 2014 Physical characterization of Warm Spitzer-observed near-Earth objects http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2014Icar..228..217T Icarus 228 217–246 2014Icar..228..217T 10.1016/j.icarus.2013.10.004 22 March 2017 1310.2000 6 Peter Veres Robert Jedicke Alan Fitzsimmons Larry Denneau Mikael Granvik Bryce Bolin Serge Chastel Richard J. Wainscoat William S. Burgett Kenneth C. Chambers Heather Flewelling Nick Kaiser Eugen A. Magnier Jeff S. Morgan Paul A. Price John L. Tonry Christopher Waters November 2015 Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V Icarus 261 34–47 2015Icar..261...34V 10.1016/j.icarus.2015.08.007 1506.00762 22 March 2017 B. Carry E. Solano S. Eggl F. E. DeMeo April 2016 Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2016Icar..268..340C Icarus 268 340–354 2016Icar..268..340C 10.1016/j.icarus.2015.12.047 1601.02087 22 March 2017 External links Spacewatch Discoveries for 1994, Spacewatch NEO Detections by Year, University of Arizona Official press release by NASA on triplet system https://web.archive.org/web/20101108232812/http://www.nasa.gov/topics/solarsystem/features/neo20090806.html 8 November 2010 (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", 136617 136617 1994CC 136617 136617 136617 136617 136617 136617 19940203 20090610 19940203