| Discoverer | CINEOS |
|---|---|
| Discovery date | August 10, 2004 |
| Epoch | 2066-03-11 |
| Observation arc | 9.35 years |
| Semimajor | 16.28 AU |
| Perihelion | 11.77 AU (outside Saturn's orbit) |
| Aphelion | 20.8 AU |
| Eccentricity | 0.27705 |
| Inclination | 19.0529° |
| Max speed | 9.8 km/s[1] |
| Min speed | 5.6 km/s (2033-Nov-30) |
| Period | 65.67 yr |
| Tjup | 3.527 |
| Dimensions | 66.17 ± 22.9 km[2] |
| Albedo | 0.053 ± 0.019[2] |
| M 2 | 9.7 |
| Last p | April 24, 2001 |
| Next p | March 22, 2066 |
'167P/CINEOS, also known as ', is a large periodic comet and active, grey centaur, approximately 66 kilometers (41 miles) in diameter, orbiting the Sun outside the orbit of Saturn. It was discovered on August 10, 2004, by astronomers with the CINEOS survey at Gran Sasso in Italy. It is one of only a handful known Chiron-type comets.
The comet nucleus (~66 km) is roughly half the size of (Bernardinelli–Bernstein) and it has a similar perihelion point just outside the orbit of Saturn.
| Comet | Nucleus diameter | Perihelion (Sun approach) | Perihelion velocity |
|---|---|---|---|
| 95P/Chiron | 215 km | 8.5 AU | 12.0 km/s |
| C/2014 UN271 (Bernardinelli–Bernstein) | 120 km | 10.95 AU | 12.7 km/s |
| 167P/CINEOS | 66 km | 11.77 AU | 9.8 km/s[1] |
Description
Due to its high Jupiter tisserand of 3.5, and a semi-major axis larger than that of Jupiter, 167P/CINEOS is classified as a Chiron-type comet, named after the groups namesake, 2060 Chiron or 95P/Chiron, designated as both minor planet and comet.[3]
167P/CINEOS was first reported as a minor planet, designated , but was found to have a very faint asymmetric cometary coma.[4] Contrary to Chiron, which is the prototype object for the dynamical group of centaurs, 167P/CINEOS has no "dual status" as comet and minor planet, and demonstrates the inconsistencies in applying the current rules for designating small Solar System bodies.[5] 167P/CINEOS not only has orbital parameters similar to those of Chiron, but also a low B–R magnitude of 1.29 ± 0.03, which places it into the group grey centaurs.[6]
In June 2039, 167P/CINEOS will pass 1.64 AU from Uranus.[3]
References
- ^ "Horizons Batch for 167P/CINEOS on 2066-Mar-18" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons. Archived 2022-06-24 at the Wayback Machine. Retrieved 2022-06-24. (JPL#22 Soln.date: 2021-Apr-15)
- ^ J. M. Bauer; T. Grav; E. Blauvelt et al. (2013). "Centaurs and Scattered Disk Objects in the Thermal Infrared: Analysis of WISE/NEOWISE Observations". The Astrophysical Journal. 773 (1): 22–33. arXiv:1306.1862. Bibcode:2013ApJ...773...22B. doi:10.1088/0004-637X/773/1/22
- ^ "167P/CINEOS – JPL Small-Body Database Lookup". ssd.jpl.nasa.gov. Jet Propulsion Laboratory. Retrieved 2012-07-12.
- ^ Romanishin, W.; Tegler, S. C.; Boattini, A.; de Luise, F.; di Paola, A. (June 2005). "Comet C/2004 PY_42 (cineos)". International Astronomical Union Circular – Central Bureau for Astronomical Telegrams. 8545: 1. Bibcode:2005IAUC.8545....1R. ISSN 0081-0304
- ^ Green, D. W. E. (June 2005). "Comets 165P/2000 B4, 166P/2001 T4, and 167P/2004 PY_42". International Astronomical Union Circular – Central Bureau for Astronomical Telegrams. 8552: 2. Bibcode:2005IAUC.8552....2G. ISSN 0081-0304
- ^ S. C. Tegler; W. Romanishin; G. J. Consolmagno (2016). "Two Color Populations of Kuiper Belt and Centaur Objects and the Smaller Orbital Inclinations of Red Centaur Objects". The Astronomical Journal. 152 (6): 210–223. Bibcode:2016AJ....152..210T. doi:10.3847/0004-6256/152/6/210. ISSN 0004-6256