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arXiv · 1508.07140

The Reactivation of Main-Belt Comet 324P/La Sagra (P/2010 R2)

Henry H. Hsieh·Scott S. Sheppard
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Abstract

We present observations using the Baade Magellan and Canada-France-Hawaii telescopes showing that main-belt comet 324P/La Sagra, formerly known as P/2010 R2, has become active again for the first time since originally observed to be active in 2010-2011. The object appears point-source-like in March and April 2015 as it approached perihelion (true anomaly of ~300 deg), but was ~1 mag brighter than expected if inactive, suggesting the presence of unresolved dust emission. Activity was confirmed by observations of a cometary dust tail in May and June 2015. We find an apparent net dust production rate of <0.1 kg/s during these observations. 324P is now the fourth main-belt comet confirmed to be recurrently active, a strong indication that its activity is driven by sublimation. It now has the largest confirmed active range of all likely main-belt comets, and also the most distant confirmed inbound activation point at R~2.8 AU. Further observations during the current active period will allow direct comparisons of activity strength with 324P's 2010 activity.

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Henry H. Hsieh, Scott S. Sheppard. 2015-08-28. The Reactivation of Main-Belt Comet 324P/La Sagra (P/2010 R2). https://doi.org/10.1093/mnrasl%2Fslv125

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