New Comet C/2021 O3 (PANSTARRS)

August 05, 2021

CBET xxxx & 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).

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

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).

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

This comet could become visible to the naked eye in 2022, reaching magnitude ~5. Anyway, as always with comets, the future magnitudes reported here are only indicative. 

By Ernesto Guido