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Volcanic activity at Tvashtar Catena, Io

Icarus

By:
, , , , , , , ,
DOI: 10.1016/j.icarus.2005.05.013

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Abstract

Galileo's Solid State Imager (SSI) observed Tvashtar Catena four times between November 1999 and October 2001, providing a unique look at a distinctive high latitude volcanic complex on Io. The first observation (orbit I25, November 1999) resolved, for the first time, an active extraterrestrial fissure eruption; the brightness temperature was at least 1300 K. The second observation (orbit I27, February 2000) showed a large (??? 500 km 2) region with many, small, hot, regions of active lava. The third observation was taken in conjunction with Cassini imaging in December 2000 and showed a Pele-like, annular plume deposit. The Cassini images revealed an ???400 km high Pele-type plume above Tvashtar Catena. The final Galileo SSI observation of Tvashtar (orbit I32, October 2001), revealed that obvious (to SSI) activity had ceased, although data from Galileo's Near Infrared Mapping Spectrometer (NIMS) indicated that there was still significant thermal emission from the Tvashtar region. In this paper, we primarily analyze the style of eruption during orbit I27 (February 2000). Comparison with a lava flow cooling model indicates that the behavior of the Tvashtar eruption during I27 does not match that of simple advancing lava flows. Instead, it may be an active lava lake or a complex set of lava flows with episodic, overlapping eruptions. The highest reliable color temperature is ???1300 K. Although higher temperatures cannot be ruled out, they do not need to be invoked to fit the observed data. The total power output from the active lavas in February 2000 was at least 1011 W. ?? 2005 Elsevier Inc. All rights reserved.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Volcanic activity at Tvashtar Catena, Io
Series title:
Icarus
DOI:
10.1016/j.icarus.2005.05.013
Volume
179
Issue:
1
Year Published:
2005
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Icarus
First page:
235
Last page:
251
Number of Pages:
17