29P/Schwassmann-Wachmann 1, 33P/Daniel, and C/2007 N3 (Lulin)
On February 20, I found C/2007 N3 (Lulin) definitely 0.2
magnitude brighter than on February 18 and easier to see with the naked-eye.
But in the 15cm at 18x it appeared somewhat smaller (perhaps my imagination)
than on February 18 (UT). I visually estimated it at 4.8 magnitude.
The following are the observations of two periodic comets
which are known for changing brightness.
0029P 2009 01 17.72604 08 00 47.92 +23 32 52.2 14.8 T 372
0029P 2009 01 25.65694 07 56 41.08 +23 38 00.0 15.0 T 372
0029P 2009 01 28.74375 07 55 06.99 +23 39 36.9 15.3 T 372
0029P 2009 02 12.48056 07 48 17.63 +23 43 51.6 12.9 T 372
0029P 2009 02 17.46111 07 46 20.40 +23 43 53.8 13.5 T 372
0029P 2009 02 18.57684 07 45 55.86 +23 43 48.6 13.7 T 372
0033P 2009 02 20.56563 11 30 28.85 +40 50 39.0 14.5 T 372
0033P 2009 02 20.59201 11 30 27.37 +40 50 47.9 14.4 T 372
The latest observations of Comet Lulin glowing in the eastern sky:
CK07N030 2009 02 20.61580 12 23 57.93 -02 13 40.8 6.0 T 372
CK07N030 2009 02 20.66458 12 23 07.39 -02 08 27.9 372
CK07N030 2009 02 20.72938 12 22 00.00 -02 01 32.2 6.0 T 372
Recently 29P/Schwassmann-Wachmann has been slightly on the
bright side showing subtle changes. The sharp nucleus is visible on and
off.
33P/Daniel reminds me of Comet Daniel-Shimizu. Dr. Hideo
Hirose (then at Tokyo Astronomical Observatory) calculated the perturbation
of the comet, which had been missing until then. In January 1937, he sent
the predictions based on the results of his calculation to Mr. Shinichi
Shimizu (Shimada city, Shizuoka prefecture) requesting search for this
comet. Mr. Shimizu was a pioneering figure for astronomical photography
in Japan. He discovered this comet using optics designed for portrait photography
of an only 8cm aperture.
In those days it seems that there were not many people involved
in astronomical photography even at professional observatories. This renowned
pair of Hirose and Shimizu reunited at the Comet Conference held in Aichi
prefecture nearly 40 years later. A 10cm equatorial telescope, which had
been used for comet discoveries, was donated to Shizuoka Prefecture Library
and displayed at the Comet Conference in Shizuoka prefecture.
A reunion after 40 years!
In those days people were more hopeful and optimistic.