Another Jupiter impact?

[Rick]

In what turns out to be a major coincidence, Anthony Wesley, an amateur astronomer in Australia, is reporting that he recorded another impact on Jupiter! This time he has video of the impact, which he claims was quite bright and lasted about two seconds.

See http://blogs.discovermagazine.com/badastronomy/2010/06/03/breaking-another-jupiter-impact/

[Rick]

BAA electronic bulletin No. 00498 -- http://www.britastro.org/
Bulletin transmitted on Sat Jun 5 11:53:13 BST 2010
(c) 2010 British Astronomical Association

New impact on Jupiter

A new impact has been detected on Jupiter.  This time the impact flash was recorded directly, by two independent amateur observers. It was first reported by Anthony Wesley (Australia) (who discovered the impact last year), and confirmed by Chris Go in a video taken at exactly the same time: 2010 June 3, 20:31:29UTC.  It was a very bright flash lasting about 2 seconds, so there can be no doubt that it was an impact; no internal event in Jupiter would produce such a bright brief flash. It was in the faded South Equatorial Belt, about 50 deg. preceding the central meridian; Wesley's preliminary measurements put it at Longitude L2 = 342.7, L3 = 159.4, Latitude 16.1 deg.S. Nothing further was seen at the impact site in the half-hour before it disappeared round the limb.

When it reappeared, this morning around 03:30 UT , observers in England, France and Italy looked for an impact spot but recorded nothing definite. However, the images were at low resolution (due to the low altitude and bright dawn sky), so the images do not exclude a smaller scar.  Observations of this site over the next few days will be very important. Even if no 'scar' is detected, this would not be surprising. The direct imaging of the SL9 impacts in 1994 by the Galileo spacecraft showed a bright flash a few seconds long like this one even for a small fragment which produced virtually no scar, probably because a small impactor can explode high in the atmosphere.  So, impacts like this could be frequent, but never before recorded, and still consistent with the rarity of larger impacts that leave obvious traces.

By the way:  Uranus is 0.5 degrees north of Jupiter at present: a good opportunity to compare the two giant planets.
______________________________________
John H. Rogers
Jupiter Section Director,
British Astronomical Association.