17 June 2016
Perihelion Distance (q)
Aphelion Distance (Q)
Click for NASA orbit diagram
Hills Observatory: 1 January 2013 to 15 February 2020
Keith Tritton (U. K. Schmidt Telescope Unit, Coonabarabran) discovered this comet on a deep
IIIa-J exposure made with the 122-cm Schmidt telescope on 1978 February 11.
Moonlight made observations impossible during the last half of February 1978 and during the
early days of March; however, the comet was found by J. H. Bulger (Harvard Observatory's
Agassiz Station) on March 10.27. He gave the nuclear magnitude as 20. The last three
observations of the comet were obtained by Shao on March 11, 13 and 14. On IAU Circular No.
3194, issued on 1978 March 15, Marsden wrote, "It is possible that the comet experienced an
outburst around the time of the Harvard observation on Feb. 15...." No observations were
The comet was not detected during the predicted returns of 1984, 1990 or 1996 and was
presumed lost. When the new comet designation system was introduced by the International
Astronomical Union in August of 1994, this comet did not receive a "P/" designation for a short-
period comet, but received a "D/" designation, which meant "it would be ill-advised or
impossible seriously to consider a prediction for a future return...."
However, on 2003 October 6, using CCD images obtained with a 0.12-m refractor, C. W. Juels
(Fountain Hills, Arizona, USA) and P. Holvorcem (Campinas, Brazil) detected a comet that proved
to be on a similar orbit to the lost comet. B. G. Marsden was able to calculate a new orbit,
published in IAU Circular No. 8215, issued 2003 October 7, which confirmed that it was indeed
identical to comet Tritton.
The comet was also recovered at its 2010 apparition.
The comet experienced six close approaches to Earth and two close approaches to Jupiter during
the 20th century and will make two close approaches to Earth and one to Jupiter during the next
30 years (from the orbital work of Kazuo Kinoshita):
- 0.26 AU from Jupiter on 2020 February 11 (increased perihelion distance from 1.36 AU to
1.57 AU and orbital period from 6.29 to 6.67 years)
- 0.91 AU from Earth on 2035 November 13
- 0.79 AU from Earth on 2043 January 9
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