Ultraviolet spectroscopy of Comet 9P/Tempel 1 with Alice/Rosetta during the Deep Impact encounter

Paul D. Feldman (1) , S. Alan Stern (2) , Andrew J. Steffl (2) , Joel Wm. Parker (2) , David C. Slater (3) , Michael A'Hearn (4) , Jean-Loup Bertaux (5) , Michel C. Festou (6)

1 Department of Physics and Astronomy [Baltimore]
2 Department of Space Studies [Boulder]
3 Space Science and Engineering Division [San Antonio]
4 Department of Astronomy [College Park]
5 SA - Service d'aéronomie
6 OMP - Observatoire Midi-Pyrénées

We report on spectroscopic observations of periodic Comet 9P/Tempel 1 by the Alice ultraviolet spectrograph on the Rosetta spacecraft in conjunction with NASA's Deep Impact mission. Our objectives were to measure an increase in atomic and molecular emissions produced by the excavation of volatile sub-surface material. We unambiguously detected atomic oxygen emission from the quiescent coma but no enhancement at the 10% (1-σ) level following the impact. We derive a quiescent H2O production rate of 9 x 10²⁷ molecules s^-1 with an estimated uncertainty of ∼30%. Our upper limits to the volatiles produced by the impact are consistent with other estimates.

Mots clés: Comet Tempel 1; Ultraviolet observations

Domaines: Planète et Univers [physics]

Paul D. Feldman, S. Alan Stern, Andrew J. Steffl, Joel Wm. Parker, David C. Slater, et al.. Ultraviolet spectroscopy of Comet 9P/Tempel 1 with Alice/Rosetta during the Deep Impact encounter. Icarus, 2007, 191 (2), pp.258-262. ⟨10.1016/j.icarus.2006.08.032⟩. ⟨insu-02245569⟩