SO2 and SO ALMA Observations of Io in and out of Eclipse
Abstract
We observed Io with the Atacama Large Millimeter /submillimeter Array (ALMA) in Cycle 5, both when the satellite went into eclipse (20 March 2018) and when it came out of eclipse (2 and 11 September 2018). The observations were taken in Band 7, between 330 and 348 GHz (1-mm band). We concentrated on different transitions of SO2 and SO.
The observations are reduced with CASA, the Common Astronomy Software Applications package, version 5.4.0. The March in-sunlight images show strong widespread SO2 emissions; several minutes after having entered eclipse, the emissions had faded considerably, and 15 min after entering eclipse global emission had disappeared and we only see emission localized to a single region on Io's surface, likely volcanic in origin. Images of the satellite in-eclipse in September, after having been in Jupiter's shade for ~2 hrs, do not show much emission, although on Sep. 2 there is one localized region. About 10 min after coming back into sunlight, the SO2 emission is at its full strength. We will present images, line profiles and models of SO2 and SO. We will compare maps of SO2 and SO with a geological map of Io, and with the spatial distribution of SO as observed at 1.7 micron with Keck in previous years (de Pater et al., 2017; BAAS #49, id.214.01).- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.P51A..05D
- Keywords:
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- 6218 Jovian satellites;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 6299 General or miscellaneous;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS;
- 5480 Volcanism;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS;
- 5499 General or miscellaneous;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS