Nucleus B of 73P/Schwassmann-Wachmann 3 begins to break up.
There were many clouds during the daytime on April 23. But
the sky began to clear up in the evening and I hurriedly went to the observatory.
Over a period of about 3 hours I observed Comet Schwassmann-Wachmann 3
Nucleus C, the brightest of all, was at 8th magnitude and
barely visible through 7x50 binoculars. I think there is a great possibility
that this will not become a naked-eye object. What do you think? However,
the tail seems to have grown quite well.
Nucleus B has become very diffuse and begun to break up into
two or more fragments. Refer to the photograph taken on April 21 at Geisei
Observatory. In the photograph the nucleus is narrow and extended into
the direction of its motion , but there is no sign of breaking up.
In the close-up image taken on April 23, the nucleus is clearly
split. It is certain that this occurred within the past two days. I measured
these two nuclei.
Is the first nucleus original Nucleus B itself?
(the lading nucleus)
2006UT RA (2000.0) Decl. m2
Apr.23.59792 15 19 33.60 +29 58 56.6 13.8 372
23.60034 15 19 34.17 +29 59 02.0 372
(the following nucleus)
Apr.23.59792 15 19 33.02 +29 58 46.8 14.2 372
23.60034 15 19 33.48 +29 58 52.9 372
As they appear stellar, the accuracy of measurement is not
bad. The leading nucleus is very clear and shining intensely. I wonder
if this is Nucleus B itself. Although the nucleus is faint, the total magnitude
is 8.9. It is hazy and extends like fog.
Past midnight, the sky became hazy as if covered by fog.
Was it dust haze again from the "yellow sand dust", which was
blown over from the deserts of China and Mongolia? The comet disappeared
into a night fog of yellow dust.