Searching for L5 Earth Trojans with DECam
Abstract
Most of the major planets in the Solar System support populations of co-orbiting bodies, known as Trojans, at their L4 and L5 Lagrange points. In contrast, Earth has only one known co-orbiting companion, 2010 TK7. Studying this population can provide interesting constraints on the dynamical history of the Solar System. Earth Trojans (ETs) can be dynamically stable for > 1 Gyr, and could be remnants of the same processes that placed Earth in its present orbit. Temporary ETs are potential Earth and Moon impactors, and therefore have implications for planetary defense as well as cratering on the Moon. Moreover, ETs of any sort are attractive targets for spacecraft missions. Unfortunately, due to the geometry of their orbit, ETs are a particularly difficult population to observe, especially from ground-based telescopes. A small number of dedicated searches have found no additional ETs. Existing upper limits leave room for 10s to 100s of undiscovered ETs up to several hundred meters in size. We present the latest results from our optical search program for ETs using the DECam instrument on the Blanco Telescope at CTIO. Our observations have the most complete coverage of the Earth's L5 cloud of any dedicated ET search. This greater coverage will allow us to place the most stringent constraints to date on this elusive population.
- Publication:
-
American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23532901M