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Reports from Geisei Observatory <May 12, 2007>

A mysterious object in NGC 4477

    At Geisei, we continue to patrol the sky for comets and asteroids using the 60cm reflector. I found a 17th-magnitude stellar object in the haze of the galaxy NGC 4477 on the film taken at midnight on May 11. I could have ignored it, but because the object was in a galaxy I checked a photograph taken on May 8. I could not find anything unusual in it. You would most likely think of a supernova, but strangely there was nothing in a photograph taken on May 13, either. What in the world could it be?

    It is not just a scratch or dust on the film surface judging from its appearance. I confirmed that there was no known minor planet in MPC's announcements which had passed that position. It could not be a new minor planet as it is as bright as 17th magnitude and the discovery of minor planets brighter than 19th magnitude is extremely rare these days. The following are the position and a photographic image of this mysterious object:
Object Seki                                           
2007UT           RA (2000.0)  Decl.        mv         
May 11.58160  12 30 03.73  +13 37 38.0    17.5     372

NGC 4477 (a galaxy in Virgo)
11-minute exposure from 22:55 on May 11, 2007

    It is an "iron-clad" law of astronomical photography to take two images of the same object or make a double exposure on the same film with a certain interval so that you can verify the existence of the object. If it is a Solar System object, its motion will be detected. It was simply a lapse of concentration on my part that two photographs of that object were not taken simply to save time. I will keep this in mind as an important lesson for the future.

C/2007 E2 (Lovejoy)

    C/2007 E2 (Lovejoy), now visible in the northern sky, has somewhat faded. I observed the comet through the 20cm refractor at 60x on the early part of the night. It was 10.5 magnitude and its coma has reduced to 3' in diameter. It should be noted, however, that sky transparency was poor because of the "yellow sand" dust. I will observe it under better conditions.

Copyright (C) 2007 Tsutomu Seki.