73P/Schwassmann–Wachmann, also known as Schwassmann–Wachmann 3, is a periodic comet that
is in the process of disintegrating.
Starting the 2011 perihelion
passage the primary component 73P-C was recovered on 28 November 2010
near apparent magnitude 21.3; it came to perihelion(closest approach to the Sun) on 16 October 2011.
Comet Schwassmann–Wachmann 3 was one of the comets discovered by astronomers Arnold Schwassmannand Arno Arthur Wachmann, working at the Hamburg Observatory in
Bergedorf, Germany.
It began disintegrating on its re-entry to the
inner Solar System in 1995, in a reaction triggered by the Sun's
heating of the comet as it emerged from the colder regions of the outer
Solar System.
Comet 73P is a parent body of meteor shower Tau Herculids.
73P/Schwassmann–Wachmann has an orbital period of slightly less than 5 1/3 years so that it comes nearest to the Earth every 16 years.
The primary fragment 73P-C has an Earth-MOID of 0.04 AU (6,000,000 km; 3,700,000 mi). 73P was originally estimated to have a core diameter of 1100 meters.
In
1995, 73P began to disintegrate. It was seen to break into four
large pieces labeled 73P-A, B, C, & D.
As of March 2006, at
least eight fragments were known: B, C, G, H, J, L, M & N.
On April
18, 2006, the Hubble Space Telescope recorded dozens of pieces of fragments B and G.
It appears that the comet may eventually disintegrate completely and cease to be observable (as did 3D/Biela in
the 19th century), in which case its designation would change from 73P
to 73D.
It is now known to have split into at least 66 separate
objects. Nucleus C is the largest and the presumed principal remnant of
the original nucleus.
I shot this image on April 6th, 2006.