J. Berthier (BDL Paris); F. Colas (BDL Paris); F. Deladerriere (OMP Pic du Midi
P. Laques (OMP Pic du Midi); J. Lecacheux (DESPA Meudon); S. Pau (DESPA Meudon)
D. Rouan (DESPA Meudon); A. Sanchez-Lavega (UPV Bilbao); D. Tiphene (Despa
Meudon).
We have tracked the spot resulting from impact G which took place just on spot D so now we have a merge of both features. This spot is the larger one with a size of about 15000 km, contains a compact dark nucleus 8500km across and extends towards southern latitudes. Multiwavelength observations from blue to 2.3 microns shows it to be low albedo at continuum wavelengths but very bright under the 890 nm and 2.2 microns methane bands.
We have fully observed the impact H at a wavelength of 2.2 microns. A strong "flash" at 19hr33min04s was preceded by a short tiny flash and by a brightness increase of Io, and followed subsequently by the formation of a bright spot in the limb extending more than 5000 km above it We have monitored subsequently the resulting low albedo cloud (in the continuum) which was similar in color and morphology to previous events.
Approximate longitudes for these features are: G (plus old D): 300dg SYS.II /10dg SYS.III (20h 10min) H : 24dg SYS.II/94dg SYS.III (21h 45min)
The spots are nearly stationnary in Sys. II.
Impact L was impressive with three consecutive flashes at 22:17:35 (UTC)
22:23:30 (UTC) and 22:28:10 (UTC), instead of one as predicted. COntinuous images were taken under the G, H and K infrared bands. The second and third events were the brightest we have observed up to now, being bright not only in the K filter but also in J and H bands. The fireball reached an altitude of a thousand km above the limb.