149P/Mueller (0149P)


Type: Periodic Perihelion date: 22 February 2019 Perihelion distance (q): 2.6 Aphelion distance (Q) : 6.1 Period (years): 9.1 Eccentricity (e): 0.39 Inclination (i): 30.4 JPL orbit diagram COBS lightcurve A 90-minute IIIa-J exposure was obtained by Jean Mueller and C. Brewer (Palomar Observatory, California, USA) with the 1.2-m Oschin Schmidt telescope on 9 April 1992. Upon examining the plate a couple of days later, Mueller found the faint trail of a possible comet. She estimated the magnitude as 17.5 and noted a "possible hint of a tail to the west." She noted a 30-minute exposure was obtained of the same region with the same telescope on 11 April and was able to locate a trail that was too weak to confirm whether it was a comet or a minor planet. R. H. McNaught (Siding Spring Observatory, Australia) photographed the object with the Uppsala Schmidt telescope on 12 April and confirmed the cometary nature. He estimated the magnitude as 17. T. Seki (Geisei, Japan) also detected the comet on 14 April and noted a magnitude of 17. The first orbit was calculated by B. G. Marsden (Central Bureau for Astronomical Telegrams). Using positions spanning the period of 9-14 April, he found the comet was moving in a short- period orbit, with a perihelion date of 27 January 1992 and a period of 9.26 years. Ultimately the perihelion date proved to be 16 February, while the period was 8.97 years. The comet was recovered by T. Oribe (Saji Observatory) on 22 December 2000 with the 1.03-m reflector. The CCD images revealed the comet was faint and stellar, with a nuclear magnitude of 20.5. Oribe obtained further CCD images on 30 January 2001, which indicated a magnitude of 19.6. The comet was followed until 28 June 2001, when it was detected by Pepe Manteca (Observatorio de Begues, Spain) using a 30- cm f/6.3 Schmidt-Cassegrain and a CCD camera. He gave the magnitude as 18.0. Observations (VEMag = visual equivalent magnitude) Date 10x10 mag Error VEmag Coma ' 08-May-19 18.83 0.05 17.8 0.4 24-May-19 19.04 0.12 18.6 0.3 02-Jun-19 18.95 0.13 17.4 0.2