Monday, August 2, 2021

New Comet C/2021 O3 (PANSTARRS)

CBET 5009 & MPEC 2021-P05, issued on 2021, August 01, announce the discovery of a new comet (magnitude ~20) on CCD images taken on July 26.5 UT with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala. The new comet has been designated C/2021 O3 (PANSTARRS)

Stacking of 15 unfiltered exposures, 240 seconds each, obtained remotely on 2021, July 30.3 from X02 (Telescope Live, Chile) through a 0.61-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 8" arcsecond in diameter (Observers E. Guido, M. Rocchetto, E. Bryssinck, M. Fulle, G. Milani, C. Nassef, G. Savini, A. Valvasori).

Our confirmation image (click on the images for a bigger version; made with TYCHO software by D. Parrott)

MPEC 2021-P05, assigns the following preliminary orbital elements to comet C/2021 O3 (PANSTARRS): T 2022 Apr. 20.49; e= 1.0; Peri. =  299.88; q = 0.28 ;  Incl.= 56.72

Credit: MPC

This comet could become visible to the naked eye in 2022, reaching magnitude ~5. Below you can see a graph generated using the software Orbitas and showing the predicted magnitude (in red) versus its elongation from the Sun. Anyway, as always with comets, the future magnitudes reported here are only indicative. 

By Ernesto Guido