10P/Tempel, also known as Tempel 2, is a periodic Jupiter-family comet with a 5 year orbital period. It was discovered on July 4, 1873 by Wilhelm Tempel.[7] The next perihelion passage is 2 August 2026 when the comet will have a solar elongation of 164 degrees at approximately apparent magnitude 8.[4] Closest approach to Earth will be one day later on 3 August 2026 at a distance of 0.414 AU (61.9 million km).[1]

10P/Tempel closest Earth approach on 2026-Aug-03[1]
Date & time of
closest approach 		Earth distance
(AU) 		Sun distance
(AU) 		Velocity
wrt Earth
(km/s) 		Velocity
wrt Sun
(km/s) 		Uncertainty
region
(3-sigma) 		Reference
2026-Aug-03 20:59 ± 1 min 0.414 AU (61.9 million km; 38.5 million mi; 161 LD) 1.42 AU (212 million km; 132 million mi) 6.5 31.0 ± 204 km Horizons

The comet nucleus is estimated to be roughly the size of Halley's Comet at 10.6 kilometers in diameter with a low albedo of 0.022.[1] The nucleus is dark because hydrocarbons on the surface have been converted to a dark, tar like substance by solar ultraviolet radiation. The nucleus is large enough that even near aphelion (furthest distance from the Sun which is near the orbit of Jupiter) the comet remains brighter than about magnitude 21.

Comet Tempel II during the 1925 apparition.

During the 2010 apparition the comet brightened to about apparent magnitude 8.[4] The most favorable apparition of 10P/Tempel 2 was in 1925 when it came within 0.35 AU (52 million km; 33 million mi) of Earth with an apparent magnitude of 6.5.[7]

Proposed exploration

The Jet Propulsion Laboratory proposed a flyby of the comet with a flight spare of Mariner 4.[8] The probe was instead used for a Venus flyby as Mariner 5.[8]

References

  1. ^ a b c d e "JPL Small-Body Database Browser: 10P/Tempel 2" (last observation: 2014-03-29; arc: 67.91 years). Jet Propulsion Laboratory. Retrieved 2010-02-24.
  2. ^ a b c d "10P/Tempel Orbit". Minor Planet Center. Retrieved 2023-08-06.
  3. ^ 10P at Kazuo Kinoshita home page
  4. ^ a b c Seiichi Yoshida (2008-01-27). "10P/Tempel 2". Seiichi Yoshida's Comet Catalog. Retrieved 2010-02-24.
  5. ^ Syuichi Nakano (2007-04-10). "10P/Tempel 2 (NK 1460)". OAA Computing and Minor Planet Sections. Retrieved 2010-02-24.
  6. ^ "Horizons Batch for 10P/Tempel 2 (90000213) on 2026-Aug-02" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons. Retrieved 2022-06-27. (JPL#K214/33 Soln.date: 2022-May-02)
  7. ^ a b Kronk, Gary W. "10P/Tempel 2". Archived from the original on 22 February 2010. Retrieved 2010-02-24. (Cometography Home Page)
  8. ^ a b Ulivi, Paolo; Harland, David M (2007). Robotic Exploration of the Solar System Part I: The Golden Age 1957-1982. Springer. pp. 57–58. ISBN 9780387493268.

External links


Numbered comets
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