Eugene Shalygin and colleagues report on their ongoing attempts to detect volcanic activity on Venus. The Venus Monitoring Camera (VMC) carried by the Venus Express orbiter is capable of making observations in the near-infrared centered around 1.01 microns, a wavelength at which thermal emissions from the planet's surface can be detected on the night side. They are making observations in likely locations, specifically the area around the Maat Mons, Sapas Mons, and Ozza Mons volcanoes (Messenger spacecraft SAR data showed recent volcanism here, geologically speaking), with the hope of detecting localized bright spots in the images.
To get an idea of how often Maat Mons might erupt, the team reviewed the eruption history of Mauna Loa on Earth since 1900. They found that even though it is an active volcano, there are only eruption events on 1.6% of the days during the 100 years they evaluated. Accounting for the length of observation on Venus, the authors calculated a probability of seeing an eruption during any particular observation at 8.6%.
Ultimately, the series of observations made with the VMC, 12 passes in all, did not reveal any suspicious hot spots that could be interpreted as volcanic events. This does not preclude the possibility that eruptions occurred during this time, but did so while Venus Express was not looking.
They recommend that they keep looking, of course (I concur).
REFERENCES:
Shalygin, E., Basilevsky, A., Markiewicz, W., Titov, D., Kreslavsky, M., & Roatsch, T. (2012). Search for ongoing volcanic activity on Venus: Case study of Maat Mons, Sapas Mons and Ozza Mons volcanoes Planetary and Space Science, 73 (1), 294-301 DOI: 10.1016/j.pss.2012.08.018
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