Groundbased Io [O I] 6300 Angstroms Observations
Abstract
In a continuation of our long-term Io monitoring campaign, high-resolution (lambda /Delta lambda =~ 120000) spectroscopic observations of the neutral oxygen 6300 Angstroms emission were obtained at the NSO McMath-Pierce main telescope in 1993-1994 and 1996 - 1998. The stellar spectrograph, equipped with an image slicer, had a 5.''2 x 5.''2 field of view. Spectra with good signal-to-noise were obtained for a significant range of Io orbital and System III longitudes. The data are examined for longitudinal and orbital phase relationships, east-west asymmetries, and long and short term temporal variability, and are compared to earlier results of Scherb and Smyth (1993,JGR,98,18729). An unexpected result is we find the [O I] flux to be correlated with the emission Doppler width. In addition, we will discuss the October 1997 observations that were concurrent with HST/STIS ultraviolet Io observations by Roesler (U Wisconsin) and Moos (JHU) (Roesler et al. 1999, Science,283,353). All ultraviolet O I and S I emission features and the [O I] 6300 Angstroms integrated emission brightened simultaneously. Furthermore, we will describe the data base of all our groundbased [O I] observations and results. This work is funded in part by NASA grant NAG5-6787.
- Publication:
-
American Astronomical Society Meeting Abstracts #194
- Pub Date:
- May 1999
- Bibcode:
- 1999AAS...194.1507O