88P/Howell is a Jupiter-family comet with a 5.5 year orbital period around the Sun. It is the only comet independently discovered by American astronomer, Ellen Howell.
Observational history
It was discovered on 29 August 1981 by Ellen Howell. Alan C. Gilmore and Pamela M. Kilmartin recovered the comet ahead of its next apparition on 6 March 1987 as a diffuse 18th-magnitude object in the night sky. During the 2009 apparition the comet became as bright as apparent magnitude 8.
The comet most recently came to perihelion on 18 March 2026. It will next come to perihelion on 8 September 2031 and on 14 September 2031 it will pass from Mars. Between 2000–2050 the closest the comet will come to Earth is in June 2042.
During the 2020 apparition the comet reached about magnitude 9.
During the 2026 apparition 88P/Howell reached about magnitude 10. It crossed the Celestial equator on 19 May 2026 becoming more visible from the Northern hemisphere at magnitude 11.
Orbit As of 2026, 88P/Howell currently has an orbit that takes it between from the Sun. Brian G. Marsden was the first to compute two orbital solutions for the comet in 8 September 1981, where he determined that the comet follows a periodic orbit around the Sun once every 5.94 years. Prior to discovery, 88P/Howell had a larger orbit until a close encounter with Jupiter reduced it after passing at a distance of from the giant planet.
On 14 September 2031, it will pass from Mars.
Physical characteristics Initial estimates of the size of its nucleus place it roughly about in diameter. However, infrared observations from the Spitzer Space Telescope in 2006 reveal a smaller nucleus of only about in diameter.
Proposed exploration In response to the New Frontiers program call for Mission 4, a team from Applied Physics Laboratory (APL) submitted a mission concept proposal called the Comet Rendezvous, Sample Acquisition, Investigation, and Return (CORSAIR) that would perform a sample return from comet 88P/Howell. The mission proposed using a harpoon-based sample acquisition system while the spacecraft itself hovers a few meters above the comet's surface. In 2019, CORSAIR was ultimately not selected in favor of the Dragonfly mission to Titan.
In 2026, 88P/Howell is selected as a backup target for another proposed NASA/JPL sample-return mission called Gelato, which could launch and rendezvous to the comet by 2030 and 2038 respectively in case its primary target, 67P/Churyumov–Gerasimenko, is unreachable.
Notes
References
External links
at the Minor Planet Center database 88P/Howell at Gary W. Kronk's Cometography 88P/Howell at Gideon van Buitenen's website 88P/Howell at the Comet OBServations Database 88P/Howell by Taras Prystavski on Twitter (29 April 2026)