Reports from Geisei Observatory <September 9, 2007>
Emails from Mr. Machholz and a photograph of C/1988 (Machholz)
Mr. Don Machholz, a famous American comet hunter, asked me
through Mr. Eiji Kato of Australia for a photograph of Comet Machholz C/1992
N1 he had discovered. It is a 15-year-old photograph and was taken at Geisei
under extremely poor conditions. The observation of this comet spanned
less than a week with only 9 observations made to determine its orbit,
two of which were not up to scratch.
At Geisei only two observations were made on each of July
9 and 10, 1992. Because there were so few observations made, I decided
to find the photographs to make more precise measurements. I searched every
corner of the old storage and checked thousands of negatives and prints
without any success. Instead of what I was looking for, I found two photographs
of the comets Mr. Machholz had discovered: C/1978 R3 and C/1988 P1. I decided
to send him those photographs. As the photograph of C/1988 P1 was particularly
bright and clear, I measured it again for its more precise position. This
comet was discovered in the south of Taurus in the predawn sky on August
6 at 8th magnitude. There were 5 independent discoverers in Japan, but
it does not bear their names.
The photograph below was made by Metcalf guiding method on
August 19 using the 60cm reflector. It was 7-8th magnitude visually.
1988UT RA (2000.0) decl. m1
Aug.19.78576 06 20 42.38 -00 35 52.8 8.1 372
19.79826 06 20 49.06 -00 35 57.4 8.0 372
C/1988 P1 (Machhplz)
7-minute exposure from 18:55, August 18, 1988, U.T.
60cm f/3.5 reflector, TMY 400 film
Gisei Observatory (372)