The constantly changing face of Jupiter

by Jason Hatton

Jupiter has provided quite a show the last few months. I have spent much of my time with the telescope observing the constantly changing Jovian cloud tops & trying to catch the mutual eclipses & occultations of the 4 galilean satellites (these mutual events occur over a period of a few months roughly every six years).

The Great Red Spot (GRS) is now reasonable prominent, appearing visually as pale salmon pink oval. There is a lot of activity around the spot. The portion of the South Equatorial Belt (SEB) following the spot is very turbulent with a lot of small ovals which seem to change shape & form daily. A portion of the South temperate belt (STB) is quite dark & distinct around the longitude of the GRS. On the opposite side of the planet to the red spot there are some dark barges in the North Equatorial Belt (NEB) & some dark belt segments in the northern hemisphere. The equatorial zone is very active, with fine festoons & wisps visible under good seeing conditions. Digital imaging reveals some fine structures including a small jetstream spot which tracked along the southern edge of the SEB until it got to the Great Red Spot hollow in early April, where it skirted around the red spot. In the southern hemisphere there are some nice white ovals in the S. Temperate region which have been changing form & position - these show up well on images, but are tricky to see through the eyepiece.

Since early February I've been regularly imaging Jupiter using a Toucam webcam. I still haven't found time to put together a web page of my Jupiter images, but most of my recent images are now accessible on the International Jupiter Watch page, along with those of other observers.

Here are direct links to some of the better image sequences, which show some of the features described above;

22-23Feb03: GRS & SSTB ovals. Some structure is visible in the Great Red Spot:

27-28Feb03: Ganymede & Ganymede shadow transit. Ganymede is much darker than the other Galilean moons, so it appears quite distinct when crossing the equatorial zone. Again the GRS is well placed on this sequence, along with turbulence / ovals in the SEB following the spot:

21-22Mar03: The portion of the SEB following the Great red spot is more quiescent than in the previous image, but the equatorial zone is very active. Note also the dark belt fragment in the Northern temperate zone:

23-24Mar03: Three of the SSTB ovals ( visible to the south of the Great Red Spot) appear to form a triplet:

29-30Mar03: The opposite side of the planet to the Great Red Spot. Both equatorial belts appear double. In the NEB, a dark barge is visible:

30-31Mar03: The GRS is moving onto the disk & a lot of fine detail is visible, particularly the festoons in the equatorial zone. The Jetstream spot is just visible on the S. edge of the SEB preceeding the red spot, this subsequently passed north of the GRS along the edge of the Red Spot Hollow in mid April.

The main IJW image page is accessible through the following link . There are many excellent images by other observers here, which show far more detail than my own images.