Activity in Centaur-like Jupiter-family Comet 2023 RN3

We present multi-filter observations of Centaur-like Jupiter-family comet 2023 RN3 conducted as part of the Las Cumbres Observatory Outbursting Objects Key Project, as well as analysis of archival data in which 2023 RN3 was expected to be present. We find clear evidence of comet-like mass loss in the form of an extended morphology on UT 2023 November 16 and 18, and an increase in intrinsic brightness of >4 mag between 2022 September and 2023 November. We also report broadband colors for the coma of g′−r′=0.61±0.03 , r′−i′=0.30±0.03 , and i′−z′=0.04±0.08 , giving a g′r′i′ spectral slope of S′=(12±2)% /100 nm.