GRS observation

by Morris Jones


Late Sunday night, early Monday morning, I saw the most amazing Great Red Spot I've ever seen on Jupiter. It was the last of a series of extraordinary nights in the San Francisco Bay Area.

Jane spent most of the night observing and sketching, and has a report in progress. (Alas she lost much of her write-up in a computer crash last night, so she's understandably a little grouchy! :) )

The red spot transit was at 2:39 a.m. local early Monday morning. I observed it at about 2:15.

The GRS was indeed red. Well, more of a pink. It filled most of the red spot hollow. The really striking observation to me was the difference in color between the GRS and the SEB. The pinkness of the GRS was decidedly different from the rusty reddish brown of the SEB. The color saturation was strong enough to make the difference in hue stand out.

It's certainly the first time in my personal astronomical history that for me the red spot was red. (Sadly I might have to give up the joke I use on the sidewalk in which I refer to the GRS as "the spot formerly known as red.")

But I have to temper that with my inexperience with this observing platform. We didn't have the 180 during the most previous opposition, so I'm comparing views with a 4-inch. I know I'm getting a lot more color saturation with the 7-inch. The other contributing factor could be the use of both eyes with a binoviewer. So I can't report on a trend, only an observation.

Immediately south of the GRS was a rod that appeared like an underscore beneath the storm, beginning and ending, it appeared, not far from the east-west extent of the GRS. Jane says as she watched Jupiter rotate, the "GRS underscore" merged in the east with the SEB.

I had to get some sleep, but Jane stayed up to observe and sketch the long trail of white ovals following the GRS, and several NEB features following.

180mm f/9 refractor, 16 mm orthoscopic eyepieces, with binoviewer, and 3x (total) barlow. Approximately 300x.