Comets - 173P/Mueller - 0173P
Type Periodic Perihelion Date 18 December 2021 Perihelion Distance (q) 4.2 Aphelion Distance (Q) 7.2 Period (Years) 13.6 Eccentricity (e) 0.26 Inclination (i) 16.5 Click for NASA orbit diagram
Hills Observatory: 1 January 2013 to 26 May 2020
J. Mueller (Palomar Observatory, California, USA) discovered this comet on a photographic plate exposed on 20 November 1993, using the 122-cm Oschin Schmidt Telescope in the course of the second Palomar Sky Survey. The comet appeared as a short, diffuse trail of magnitude 17.5–18. J. D. Mendenhall and Mueller confirmed the discovery on a second photographic plate exposed using the same telescope on 21 November and an independent confirmation was made by D. D. Balam and J. B. Tatum (Dominion Astrophysical Observatory, Victoria, British Columbia, Canada) on images obtained on 23 November , using the 182-cm reflector and a CCD camera. In 2008, M. Meyer found a prediscovery image of this comet on a plate exposed during the second Palomar Sky Survey on 25 September 1992, when the magnitude was estimated as 17.9. The comet was apparently at its brightest during early January of 1994, when T. Seki (Geisei, Japan) acquired images which revealed the comet at magnitude 16.5-16.8. The comet was last detected on 1 February 1995, when astronomers at Kitt Peak National Observatory (Arizona, USA) acquired a CCD image using the Spacewatch telescope at a nuclear magnitude of 21.6. The comet was recovered on three images acquired with the 1.5-m reflector by E. J. Christensen (Mt. Lemmon Survey, Arizona, USA) during 7 October 2005. The magnitude was given as 18.0, the condensed coma was 8" across, and there was a curved tail extending 20" in PA 250-280 degrees. The comet peaked at a brightness of 16-17 at the beginning of 2007. Date 10x10 mag Error Kphot mag Coma ' 23-Dec-19 18.01 0.05 17.3 0.3 13-Jan-20 18.01 0.04 17.7 0.3 23-Jan-20 18.04 0.04 17.8 0.2 10-Feb-20 18.18 0.05 18.1 0.2 17-Feb-20 18.34 0.09 18.1 0.2 09-Mar-20 18.37 0.10 18.0 0.2