Wed Jul 20 03:23:54 1994
As reported earlier, we witnessed the fireball from the impact of
Fragment L, with a maximum near UT 22:23 July 19. We have now reduced
the near infrared spectrum we obtained of the fireball, and find (at
a spectral resolution of 3500) that its output is totally dominated
by continuum from about 2.06 to about 2.20 microns. There are no
emission lines over this range, which includes overtone lines of
H3+, H_2, and the Br gamma hydrogen recombination line.
>From UT 2:30 to 4:30, we obtained a high S/N spectrum at R=3500 of the entire belt containing the impact sites, covering the spectral range 2.07 to 2.42 microns. Because of the very low surface brightness of Jupiter over most of this range, it should be very well suited to identify any subtle spectral features in the impact ejecta.
Both these spectra and additional low resolution (R = 800) spectra of the ejecta are being reduced.
-- Milagros Ruiz, Marcia and George Rieke, Dennis Means at the
Steward Observatory 90-Inch