Ground Observations of radiation from the OSIRIS-REx Sample Return Capsule during Earth Return

On the morning of September 24, 2023, the OSIRIS-REx sample return capsule returned to earth, Utah USA. At that time, the radiation intensity from the capsule was measured and observations were conducted from the ground to contribute to the prediction of the capsule’s trajectory. The capsule returns of STARDUST, Hayabusa, and Hayabusa2 have all been at night, but this was the first time that observations were conducted after sunrise, which made for a difficult environment for ground-based observation. However, we were able to successfully observe the capsule using a fixed camera and identify its trajectory on the celestial sphere. In addition, we estimated the radiation intensity history by analyzing these capsule images.