Estimating the Change in the Mutual Orbit of Dimorphos Due to the DART Impact Using Lightcurve and Radar Observations
Abstract
Binary near-Earth asteroid 65803 Didymos is the target of NASA's Double Asteroid Redirection Test (DART) mission, a test of the kinetic impactor approach to planetary defense (Cheng et al., 2016). The spacecraft was launched in 2021 November and will impact Dimorphos, the satellite of Didymos, on 2022 September 26 at 23:14 UT. The primary objectives of the DART mission are to shorten the orbital period of Dimorphos, measure the change using ground-based observations, and estimate the momentum transfer efficiency of the impact. The DART impact is expected to reduce the orbital period of Dimorphos by at least 7 minutes (Cheng et al., 2016, Rivkin et al. 2021); the minimum change for mission success, a "level 1 requirement," is at least 73 seconds. Ground-based photometric observations of the system are planned between July 2022 to March 2023 and will yield lightcurves showing eclipses and occultations between the two components. Didymos will also be observed with monostatic and bistatic radar configurations using the Goldstone and Green Bank telescopes between September 27, about 11 hours after the DART impact, and October 22. We will use the times of the lightcurve mutual events and delay and Doppler measurements of Dimorphos relative to Didymos to estimate the mutual orbit parameters and the change in the orbit period due to the DART impact. We will discuss initial results at the conference.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.P53B..01N