Comet P/2015 F1 (Panstarrs)

R. Weryk and R. Wainscoat, Institute for Astronomy, University of Hawaii, report the discovery of another apparent comet in four w-band exposures taken with the 1.8-m Pan-STARRS1 telescope at Haleakala on Mar. 21.6 UT (discovery observations tabulated below); the object shows a tail extending for at least 5" towards position angle approximately 285 degrees (the object is located close to an image defect that makes precise morphology measurements, including tail length, difficult). 2015 UT R.A. (2000) Decl. Mag. Mar. 21.58025 16 37 43.57 -22 38 43.2 19.1 21.59087 16 37 44.00 -22 38 44.7 19.0 21.60151 16 37 44.42 -22 38 46.4 19.0 21.61215 16 37 44.85 -22 38 48.1 18.8 Five 60-s follow-up CCD images obtained by Wainscoat and M. Micheli using the 3.6-m Canada-France-Hawaii Telescope (queue observer P. Forshay) on Mar. 22.6 UT show the object to be clearly cometary, displaying a bright and thin tail at least 1' long toward p.a. 280 deg; the red magnitude was measured as 19.0- 19.2. After the comet was posted on the Minor Planet Center's PCCP webpage, W. H. Ryan obtained R-band images with the Magdalena Ridge Observatory 2.4-m f/8.9 reflector on Mar. 22.44-22.47 that yield magnitude 17.7 and showing a prominent tail in p.a. about 280 deg. The available astrometry, the following preliminary elliptical orbital elements by G. V. Williams, and an ephemeris appear on MPEC 2015-F119. T = 2015 Jan. 24.7330 TT Peri. = 173.1194 e = 0.428308 Node = 40.7475 2000.0 q = 2.559488 AU Incl. = 2.7913 a = 4.477043 AU n = 0.1040440 P = 9.47 years