Astronomy Cmarchesin

Releases from NASA, NASA Galex, NASA's Goddard Space Flight Center, Hubble, Hinode, Spitzer, Cassini, ESO, ESA, Chandra, HiRISE, Royal Astronomical Society, NRAO, Astronomy Picture of the Day, Harvard-Smithsonian Center For Astrophysics, etc.

Tuesday, September 25, 2007

SOHO's new catch: its first officially periodic comet

Credits: ESA/ NASA/ SOHO

The location of the comet P/2007 R5 (SOHO) is indicated in all three panels in the picture. The panels show pictures of observations taken with SOHO’s Large Angle and Spectrometric Coronagraph Experiment (LASCO). The comet has a small orbit, taking four years to once circle the Sun.
For the first time, LASCO has found a rare type of comet called a periodic comet (which flies by the Sun at regular intervals). While many SOHO comets are believed to be periodic, this is the first one that has been conclusively proven and officially declared as such.

The comet faded as quickly as it brightened, and soon became too faint for SOHO's instruments to see it. Estimates show that P/2007 R5 (SOHO) is probably only 100-200 metres in diameter. Given how small and faint this object is, and how close it still is to the Sun, it is an extremely difficult target for observers on Earth to pick out in the sky.