103P/Hartley
| Discovery | |
|---|---|
| Discovered by | Malcolm Hartley |
| Discovery date | 15 March 1986 |
| Orbital characteristics | |
| Aphelion | 5.87 AU (Q) |
| Perihelion | 1.05 AU (q)[1] |
| Semi-major axis | 3.46 AU (a) |
| Eccentricity | 0.694 |
| Orbital period | 6.46 years |
| Inclination | 13.6° |
| Last perihelion | May 17, 2004[2] |
| Next perihelion | October 28, 2010[1] |
Comet Hartley 2, officially designated 103P/Hartley is a small periodic comet with an orbital period of 6.46 years.[1] It was discovered by Malcolm Hartley in 1986 at the Schmidt Telescope Unit in Siding Spring, Australia.[1] Its diameter is estimated to be 1.2[3] to 1.6 km.[1]
There is a planned flyby of Hartley 2 by the Deep Impact spacecraft with a closest approach of 700 kilometers on November 4, 2010.[4] This is part of the EPOXI mission.[5]
The comet will pass within 0.12 AU of the Earth on October 20, 2010,[6] which is only eight days before coming to perihelion (closest approach to the Sun) on October 28, 2010.[1] During this passage, the comet may be visible to the naked eye at apparent magnitude 5,[7] in the constellation Cygnus, if you know where to look and are viewing from a dark sky location. Binoculars should make it an easy target.
Observation by the Spitzer Space Telescope in August 2008 showed the comet nucleus to have a radius of 0.57 ± 0.08 km and a low albedo of 0.028.[4] The mass of the comet is estimated to be about ~3×1011 kg.[4] Barring a catastrophic breakup or major splitting event, the comet should be able to survive up to another 100 apparitions (~700 years) at its current rate of mass loss.[4] After the 2010 perihelion passage, not accounting for nongravitational forces, Hartley 2 is estimated to come back to perihelion around April 20, 2017.[8]
See also
References
- ^ a b c d e f "JPL Small-Body Database Browser: 103P/Hartley 2". Jet Propulsion Laboratory. 2008-06-04 last obs. Retrieved 2010-02-23.
{{cite web}}: Check date values in:|date=(help) - ^ Seiichi Yoshida (2006-07-16). "103P/Hartley 2". Seiichi Yoshida's Comet Catalog. Retrieved 2010-02-23.
- ^ EPOXI Mission Status, NASA/University of Maryland, December 2, 2007.
- ^ a b c d Lisse, C. M. (2009). "Spitzer Space Telescope Observations of the Nucleus of Comet 103P/Hartley 2". American Astronomical Society, DPS meeting #41, #20.08. 121: 968–975. Retrieved 2010-02-23.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) (arxiv) - ^ Tune, Lee; Steigerwald, Bill; Hautaluoma, Grey; Agle, D.C. (December 13, 2007). "Deep Impact Extended Mission Heads for Comet Hartley 2". University of Maryland, College Park. Retrieved 7 August 2009.
- ^ a b "JPL Close-Approach Data: 103P/Hartley 2". 2008-06-04 last obs. Retrieved 2010-02-23.
{{cite web}}: Check date values in:|date=(help) - ^ Jonathan Shanklin. "Comet Prospects for 2010" (PDF). British Astronomical Association (Comet Section). Retrieved 2009-02-25.
- ^ Donald K. Yeomans and Alan B. Chamberlin. "Horizons Ephemeris". JPL Solar System Dynamics. Retrieved 2010-02-23.
External links
- Orbital simulation from JPL (Java) / Horizons Ephemeris
- 103P/Hartley 2 magnitude plot for 2010
- 103P/Hartley 2 page on the Cometography web site (extensive history and images)
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