121P/Shoemaker–Holt
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| Discovery | |
|---|---|
| Discovered by | Carolyn S. Shoemaker Eugene Merle Shoemaker Henry E. Holt |
| Discovery date | March 9, 1989 |
| Designations | |
| 1989j; 1988 XI; 1995 Q3 | |
| Orbital characteristics | |
| Epoch | March 6, 2006 |
| Aphelion | 5.376 AU |
| Perihelion | 2.65 AU |
| Semi-major axis | 4.013 AU |
| Eccentricity | 0.3396 |
| Orbital period | 8.039 a |
| Inclination | 17.7218° |
| Last perihelion | September 8, 2013[1] September 1, 2004 |
| Next perihelion | 2023-Jun-28[2] |
| Physical characteristics[3][4][5] | |
Mean radius | 3.61 km (2.24 mi) |
| ~10 hours | |
| (V–R) = 0.53±0.03 | |
121P/Shoemaker–Holt, also known as Shoemaker-Holt 2, is a periodic comet in the Solar System with an orbital period of about 8 years. The comet was discovered by Carolyn S. Shoemaker, Eugene M. Shoemaker, and Henry E. Holt on 9 March 1989. The comet then had an apparent magnitude of 13, was diffuse and had a tail about 2 arcminutes long.[6] It was recovered by James V. Scotti on 29 August 1995 in images obtained as part of the Spacewatch survey.[7]
The nucleus of the comet is estimated to have a radius of 3.87 km based on infrared imaging by the Spitzer Space Telescope, when the comet displayed dust emission.[4] Observations of the comet from the Isaac Newton Telescope indicate an effective radius of 3.61 kilometers. The rotational period was calculated to be 10 hours, but with high uncertainty.[3]
References
- ^ Syuichi Nakano (2010-04-28). "121P/Shoemaker-Holt 2 (NK 1925)". OAA Computing and Minor Planet Sections. Retrieved 2012-02-25.
- ^ "121P/Shoemaker-Holt Orbit". Minor Planet Center. Retrieved 2014-06-17.
- ^ a b C. Snodgrass; S. C. Lowry; A. Fitzsimmons (2008). "Optical observations of 23 distant Jupiter Family Comets, including 36P/Whipple at multiple phase angles". Monthly Notices of the Royal Astronomical Society. 385 (2): 737–756. arXiv:0712.4204. Bibcode:2008MNRAS.385..737S. doi:10.1111/j.1365-2966.2008.12900.x.
- ^ a b Y. R. Fernández; M. S. P. Kelley; P. L. Lamy; I. Toth; O. Groussin; et al. (2013). "Thermal properties, sizes, and size distribution of Jupiter-family cometary nuclei". Icarus. 226 (1): 1138–1170. arXiv:1307.6191. Bibcode:2013Icar..226.1138F. doi:10.1016/j.icarus.2013.07.021.
- ^ M. M. Knight; R. Kokotanekova; N. H. Samarasinha (2023). "Physical and Surface Properties of Comet Nuclei from Remote Observations". arXiv:2304.09309 [astro-ph.EP].
- ^ Green, Daniel (10 March 1989). "IAUC 4755: 1989j; U Gem; 1989B; N Vul 1987". www.cbat.eps.harvard.edu.
- ^ Scotti, J. V.; Green, D. W. E.; Marsden, B. G. (1 September 1995). "Comet P/1995 Q3 (Shoemaker-Holt 2)". International Astronomical Union Circular (6219): 2. ISSN 0081-0304.
External links
- Orbital simulation from JPL (Java) / Horizons Ephemeris
- 121P/Shoemaker-Holt 2 – Seiichi Yoshida @ aerith.net
- 121P at Kronk's Cometography


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