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
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.