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Reports from Geisei Observatory <January 12, 2007>


C/2006 P1 (McNaught) , 2P/Encke, P/2007 A1 (Lovas) , C/2006 XA1 (LINEAR) , and other comets

    C/2006 P1 has a small perihelion distance, but I was able to catch it at 17:20 on the evening of January 11 with the 20cm refractor at 40x, which was mounted on the 60cm reflector. The nucleus was completely stellar with a very faint fan-shaped tail above it. The comet was seen in reddened evening clouds in twilight and it was difficult to make a magnitude estimate. Judging from my past experience with comets under similar conditions, I visually estimated its magnitude to be -1. I observed for about 10 minutes, but was interrupted by clouds on and off, and then it finally was hidden by the clouds. The nucleus was bright, but it was far from what was expected of a great comet. The comet will move south at a fast pace and will become more and more difficult to observe from the Northern Hemisphere.

    I have been observing the famous comet Enke located low in the southwestern sky. It seems to be 2 magnitudes fainter than predictions in the 2006 Comet Yearbook. In case a magnitude formula is determined from visual observations when the comet is near perihelion and bright, photographic magnitudes at perihelion tend to be fainter when the perihelion distance is large. The predicted magnitude is 15.

    PK07A010 is Comet Lovas 2 which was discovered in 1986. It hadn't been recovered for 20 years because of insufficient observations and lack of precise measurements. Comet Lovas 2 was discovered in the same year as Halley's Comet returned. I observed Lovas 2 many times at Geisei. Its magnitude at the time of recovery was about 18 and very faint, but Geisei's observation below indicates it brightened to 15. This comet was thought to be lost. It hadn't been netted because of a large ΔT. I made an extensive search at Geisei at each of its return and found it completely outside the field where it had been predicted to be.

    CK06X01A, given in the last line below, is a new comet recently discovered by LINEAR. It was in the northern Milky Way and many of the photos showed the comet superimposed on the stars. It was at about 16th magnitude, bright enough for a CCD camera with a telescope larger than 15cm. The coma was approximately 20" in diameter without any tail. Mr. Kenichi Kadota estimates its magnitude to be 15.9.

    I was searching for the lost comet Denning in late November and realized that it was only about 1 degree from another lost comet Skiff-Kozai. I had made an extensive search for this comet without success. Predictions are provided in Comet Yearbook from OAA every year. The orbit calculator, Mr. Kenji Muraoka, says that the predicted positions could possibly be quite a long way from its actual positions. Some day in the future it may be captured by LINEAR's net. Geisei's 60cm reflector operates with serious trouble, but I continue to observe relying on my skills and experience.

    Recently, four minor planets discovered by Geisei have been named. I was particularly pleased with the naming of Haneda, commemorating Mr. Toshio Haneda's discovery. Comet Heneda-Campos is another lost comet. I promised him about 20 years ago that I would recover it at Geisei before long. That promise now weighs heavily on my mind. Mr. Haneda's soul riding on Minor Planet 23504 must be wandering in space looking for his comet.
    PK07A010   2007 01 11.42569 23 00 44.51 -04 59 13.1          15.5 T      372
0002P          2007 01 09.41649 23 14 47.90 +03 17 37.1          17.5 T      372
    CK06X01A   2007 01 11.44097 02 27 18.60 +53 08 30.4          16.5 T      372
    CK06X01A   2007 01 11.45556 02 27 18.84 +53 08 20.4          16.3 T      372
Observations were made by Tsutomu Seki with the 60cm f/3.5 reflector.
The number 372 is Geisei's observatory code.


Copyright (C) 2007 Tsutomu Seki.