2023 Recovery Observations and Characterization of the Active Centaur P/2010 TO20 (LINEAR-Grauer)

We report the recovery of the Centaur P/2010 TO20 (LINEAR-Grauer) on CCD imaging data from three separate dates in 2023 April, May, and June from the 8.1 m Gemini South Telescope, representing its first known detections since 2012. The recovery observations display a compact coma and tail, consistent with ongoing activity after its recent 2022 November 27 perihelion passage. We estimate a nucleus radius upper-limit of r n ≤ 2.7 km. Due to the current uncertainty inherent in the nucleus’ true size, we report a plausible range for the dust production of 2.7 cm ≤ Af ρ ≤ 14.5 cm after subtraction of an assumed nucleus flux based on radii of 2.7 km and 0.5 km, respectively. P/2010 TO20 experienced a recent and well-defined orbital change and associated change in thermal environment, making it an exciting target through which to study Centaur activity drivers and their evolution as their orbits change in real-time.