SEB Revival

Started by Martian, 01/28/2003 12:39AM
Posted 01/28/2003 12:39AM Opening Post
Some observers on this forum have mentioned an intensification or fading of certain belts over the disk of Jupiter. This is a phenomena that is cyclic at times, but mostly sporadic. One such example is the South Equatorial Belt (SEB) revival.

There have been 14 SEB revivals between the years 1919 and 1990 according to John Rogers in his encyclopedic work on Jupiter titled "The Giant Planet Jupiter" (recommended for die-hard planetary observers, although a little expensive). The SEB revival occurs when the SEB begins to fade over a period of a few months and remains faint between one to three years. The last SEB revival occurred in 1989 and lasted for approximately one year. The fading of the SEB is not always complete as a remnant of the belt can persist (northern or southern). I was fortunate to witness such a fading using large quality instruments (10" F/15 refractor and C14) between 1989 and 1990. The appearance of the planet for veteran Jupiter observers was very eerie as even small instruments normally show the two major equatorial belts (NEB and SEB). As the SEB begins to fade the Great Red Spot (GRS) intensifies to a dark (or "blood red") color. This gives the planet the appearance of a giant cyclops looking back at us. I have attached an observation of Jupiter made in 1990 showing the SEB fading compared to another observation made in 2001 when the SEB was prominent and the GRS faded.

The question of the fading of the Equatorial Belt (EB, or Band) within the Equatorial Zone (EZ) is a sporadic activity of this region of Jupiter. This belt (band) is usually composed of the southern projections of the blue festoons noted along the southern border of the NEB (NEB-S) combined with fragmentary dark sections within the EZ. The EB is enhanced when bright ovals are visible adjacent to it, especially over the northern half of the EZ. This belt is especially notable when festoon activity over the NEB-N is increased.

I hope that this small lesson helps to better understand the king of the planets.

Carlos

Attached Image:

Martian's attachment for post 3424
Posted 01/28/2003 01:33AM #1
Hi Carlos,

Thanks for the cycle information.

When I got back into astronomy in the 1980s I eventually bought a C8 anf noticed the 1990 SEB fade as you show in your drawing. That's when I thought something was wrong with my scope. smile

Great drawings. I'll be out for Jupiter a little later tonight. If I don't freeze, I'll try for Venus as well.

Thanks, Sol Robbins