Search for CO2/CO Band Emission in Active Asteroid 324P
Abstract
Until a few decades ago, the distinction between asteroids and comets seemed to be simple: comets exhibit activity in the form of a coma and/or a tail as a result of the sublimation of surface ices, whereas asteroids are inactive, rocky bodies. The separation between the two groups became less clear with the discovery of asteroidal bodies that exhibit comet-like dust activity - the active asteroids. For some of those objects, disruption or mass loss due to rotational destabilization or recent collisions are the most likely processes causing the activity. Other objects display recurrent dust activity near perihelion that seems to be caused by the sublimation of ices, but gases have never been directly measured in them. We propose the first Spitzer observations of recurrently active asteroid 324P to search for emission from CO2 or CO. Our observations will detect emission from either gas with unprecedented sensitivity and provide the first ever confirmed detection of volatiles in an active asteroid. We will measure the CO2/CO gas production rates - or put upper-limits on them in the case of a lack of emission. The detection of sublimation-driven activity in active asteroids provide important constraints on the volatile inventory of the inner Solar System and Solar System formation models, gives insight into volatile preservation/retention in asteroidal bodies, and may be relevant to primordial terrestrial water delivery scenarios, as well as future asteroid resource utilization. This proposal conforms with the Spitzer Cycle 12 focus on planetary science programs observing targets in our Solar System.
- Publication:
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Spitzer Proposal
- Pub Date:
- October 2015
- Bibcode:
- 2015sptz.prop12043M