Copyright 2009 Starry Mirror

The

TM

Astronomy From West Virginia

WATCHING A COMET CRASH INTO JUPITER

On the night of July 18-19, we observed an unusual sight as a comet evidently crashed into Jupiter, sending shock waves across the planet's surface and leaving a dark bruise several thousand miles across.

We were performing photometry of P Cygni when we noticed Jupiter coming from behind our pine tree.  We turned the telescope on the planet and saw the usual bland features.  At 1235am Eastern time, it was thought that a flash was seen near the southern polar hood.  However, this was quickly discounted because it is not unusual to see flashes when squinting through a high-power eyepiece.  They are apparently caused by eye or nervous system errors.

After looking over Jupiter's moons, which appear as distinct disks in our telecope, we went back to the planet.  At that time, it was noted that a bulls-eye pattern was emanating from a spot near the southern polar hood.  The pattern was difficult to see in the turbulent air, and after a while it was not visible at all.  It was decided that the rings were a trick of the vision, as often occurs when observing planets visually.

Closer examination of the dark spot revealed that it did not appear particularly unusual, as it was only a little darker than the nearby banding and appeared as a protrusion from the hood or band in the area.  At that point, we closed up the observatory and went to bed.  Little did we know that we had witnessed an important event.

We have been excited to have observed the event we saw.  When the comet in 1994 crashed into Jupiter, the collisions could not be seen directly, because they happened on the back side of the planet.  Seeing one in person was exciting, and it is apparent that Jupiter sweeps up objects more often than one might have expected.  It really is the "vacuum cleaner of the Solar System!" - GW

A depiction of Jupiter at 1245am ET July 19, 2009. 

NOTE : ADDED 07/24 : We are not claiming to have seen the collision which caused the dark spot.  It may have already been there.  We may have seen a small fragment hit.  It was only a flash.  We are only noting what we did see.  We are not trying to cut into anyone's discovery! We were too stupid to even realize what was going on at the time, but we won't make that mistake again.  - GW