The Primary Volatile Composition of Comet C/2015 ER61 (PANSTARRS)

In the outer edges of the solar system exist two regions: the Kuiper belt and Oort cloud. These two regions have a high amount of icy bodies (comets) orbiting the Sun. Comets located within the Oort cloud and Kuiper belt contain an ancient codex to the solar systems contents, before the formation of our solar system. Presented are near-infrared, high-resolution (λ/Δλ ~40000) data obtained from the immersion-grating echelle spectrograph iSHELL at the 3m NASA Infrared Telescope Facility (IRTF) in Maunakea, Hawaii of the Oort cloud comet C/2015 ER61 (PANSTARRS). Observations took place on April 15 and 17 in 2017 while the comet was declining after a dramatic outburst. We used two settings (LCustom and LP1) to measure the production rates and abundances (or upper limits) of H2O, CH3OH, C2H2, C2H6, HCN, and H2CO. We found the comet to be enriched in C2H2, normal in H2CO, and depleted in other detected volatiles compared to other Oort cloud comets