C/2023 RS61 (PANSTARRS)

Type: Periodic Perihelion date: 3 December 2028 Perihelion distance (q): 8.0 Aphelion distance (Q) : 15.8 Period (years): 41 Eccentricity (e): 0.33 Inclination (i): 19.9 JPL orbit diagram COBS lightcurve Atlas PanSTARRS 2 discovered a 22nd magnitude Chiron-type comet in images taken with the 1.8 m Ritchey-Chretien on 15 September 2023. Subsequently pre-discovery images were found back to 2015. The CBET noted that variation in the published magnitude suggests an outburst of some five magnitudes sometime between 2015 and 2017, with the comet fading again by 2020. The comet was observed in August 2025 by Roberto Haver and found to be three magnitudes brighter than expected from the mean ephemeris. Archive observations from the ZTF suggest that the outburst occurred between 8 - 10 August , and that the comet and ejecta are unusually red. Observations (VEMag = visual equivalent magnitude) Date 10x10 mag Error VEmag Coma ' 19-Feb-26 18.8 0.2