Comets - 110P/Hartley - 0110P
Type Periodic Perihelion Date 18 October 2021 Perihelion Distance (q) 2.5 Aphelion Distance (Q) 4.7 Period (Years)   6.8 Eccentricity (e)   0.32 Inclination (i)   11.7 Click for NASA orbit diagram
Hills Observatory: 1 January 2013 to 13 August 2019
COMETS COMETS
DEEP SKY DEEP SKY
Malcolm Hartley discovered this comet on plates exposed on 19 and 22 February 1988 with the U.K. Schmidt Telescope Unit at Siding Spring. He estimated the total magnitude as 16.5 on the 19th. He added that the plate exposed on the 22nd revealed a tail extending 10 arc minutes towards the northwest. Following the announcement on 23 February, Carolyn and Eugene Shoemaker found the comet on a plate exposed on the 19th, just a few hours prior to the earliest Siding Spring photo. The Shoemaker plate had been obtained with the 0.46-m Schmidt telescope at Palomar Observatory. Using images reported by Hartley for the period of 19 to 25 February, as well as the Shoemaker images, Daniel W. E. Green (Central Bureau for Astronomical Telegrams) computed the first orbit which was first published on 1 March. It was an elliptical orbit indicating a perihelion date of 1 August 1987, a perihelion distance of 2.44 AU, and an orbital period of 6.76 years. Following the acquisition of further observations, Brian G. Marsden (Central Bureau for Astronomical Telegrams) computed a revised orbit which indicated a perihelion date of 14 July 1987, a perihelion distance of 2.45 AU, and an orbital period of 6.85 years. More refined orbits following the final observation on 19 May indicated this latter orbit was nearly on target, although the orbital period was 6.83 years. J. V. Scotti (University of Arizona, USA) recovered this comet with the 0.91-m Spacewatch telescope at Kitt Peak on 23 and 24 June 1993. He gave the total magnitude as 19.5-19.7. Scotti also noted that the CCD image of the 23rd showed a coma diameter of 10 arc seconds, a tail extending 0.54 arc minute toward the west, and a nuclear magnitude of 22.1. The precise positions indicated the prediction for this return required a correction of +0.49 day. The apparition of 1994 showed astronomers the comet could be followed for some time. With the recovery in 1993, observations contined until 19 April 1995, which gave a duration of visibility of 665 days. The comet was next expected to pass perihelion on 21 March 2001 and it was recovered on 30 May 1998 by Christian Veillet (Mauna Kea, Hawaii, USA) using the 3.60-m Canada-France-Hawaii Telescope. The magnitude was given as 22.7 and the comet was found 1026 days prior to perihelion. The comet attained a maximum total magnitude of 13 during the spring of 2001. Date 10x10 mag Error Kphot mag Coma ' 18 Nov 14 15.76 0.02 15.1 0.3 25 Nov 14 15.55 0.01 15.1 0.2 3 Dec 14 15.45 0.02 14.6 0.3 12 Dec 14 15.23 0.02 14.2 0.4 23 Dec 14 14.92 0.02 13.9 0.4 30 Dec 14 14.74 0.01 13.5 0.3 19 Jan 15 15.24 0.02 14.1 0.3 26 Jan 15 15.56 0.02 14.2 0.4 5 Feb 15 15.88 0.04 14.7 0.3 17 Feb 15 16.13 0.03 14.7 0.3 25 Feb 15 16.40 0.02 15.4 0.2 5 Mar 15 16.63 0.05 16.1 0.2 12 Mar 15 16.81 0.04 15.7 0.2 21 Mar 15 17.02 0.04 16.4 0.2 08-Apr-15 17.39 0.09 16.5 0.2 19-Apr-15 17.34 0.01 16.1 0.2 10-May-15 17.89 0.05 17.6 0.2
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