DDT observations of five Mars Trojan asteroids

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• Emery, Josh
;
• Mueller, Michael
;
• Rivkin, Andrew
;
• Spahr, Tim
;
• Stansberry, John

Abstract

Mars Trojan asteroids are the only small bodies known to inhabit dynamically stable orbits in the inner Solar System. By studying these objects, we are directly studying the building blocks of terrestrial planets. We have recently completed two papers that demonstrate, surprisingly, that the compositions and formation environments of the brightest Mars Trojans are remarkably diverse. These recent results used the best available ground-based facilities, so to extend these results we must turn to Spitzer. We propose here to obtain Spitzer measurements of five Mars Trojans (of eight known). We will determine albedos -- a good proxy for composition -- for these five objects through IRS PUI imaging (in combination with new ground-based data). We will also obtain a low resolution spectrum of the brightest Mars Trojan to calibrate our thermal models and study that object's mineralogy. The total requested time is small. DD time is required because these five objects have no visibility windows during Cycle 5, but are available during Fall/Winter, 2007.