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Reports from Geisei Observatory <September 14, 2010>


Photograph of C/2009 R1 (McNaught)

    The extraordinary heat wave seems to have passed the worst at last. I wonder how people have coped with it.
    Here is my observation of 103P/Hartley. Having continued to photograph this comet with slow optics of the 70cm telescope, I was thinking this comet was so slow to become brighter than 14th to 15th magnitude. Then, looking at it through the 70cm scope this morning for the first time, I was surprised. The coma, which hadn't showed up in photographs, was large and shining brightly. The following are my visual observations:
2010UT       m1  dia.  DC Trans   Seeinng       Inst.
Sept.13.704  8.5  10 7  4/5     4/5     70cmL. 98X T.Seki

2010UT       m1  dia.  DC Trans   Seeinng       Inst. 
Sept.13.704  8.5  10 7  4/5     4/5      70cmL. 98X T.Seki
    There are always errors in visual estimate of large diffused object like this. This comet, I thought, would not be visible, judging from the photographs taken by slow optics, but it had actually been steadily brightening. However, compared with the initial prediction, it is still on the faint side. We should watch its future brightness changes.
    After completing the observation with the 70cm telescope, I moved to the observing shed to search the eastern sky with the 15cm binoculars for the first time in many weeks. Generally, sky conditions were good. I brought the binocular field very close to the spot where Comet Ikeya-Seki had appeared on September 19, 1965. I remembered a bright waning moon had been shining that night. Tonight, it was still 5 days earlier than the day of the discovery. I saw a familiar pattern of stars. "This is the time!" My winding watch was ticking the time, just like the moment I had discovered the comet. It was 4 o'clock in the morning. The watch brought back the memory of my elation of the discovery.


Copyright (C) 2010 Tsutomu Seki.