At 3:40am, a noticeable blob peaked its way into view moving across Jupiter’s surface. Located where the missing southern cloud belt should have been, it became apparent very quickly that this was something I had wanted to view since childhood. The location and size left no doubt that this was the Great Red Spot (GRS) of Jupiter.
Earlier views of Jupiter around 3:00am had shown the basic cloud belts, but its fast 10 hour rotation (Jupiter day) brought about new features quickly. With a size between two and three times that of Earth, it is the largest storm in the solar system. Over the past couple hundred years the GRS has varied in size and faded in and out but has constantly remained one of the most interesting features to view in the solar system. To help with observing, I found putting half of a polarizing filter on my eyepiece cut down on the glare (I’ve also found that a full polarizing filter works as well and can be adjusted to best effect). This reduction in brightness, brought much needed contrast that allowed another smaller blob to pop into view just to the lower left of the more massive GRS. I’m not sure if this was Red Junior (GRS’ little son) or just a random cloud system near by. Another first, came from noticing the inconsistencies of the cloud belts. What had appeared as straight lines in the past revealed themselves to be imperfect clouds with wrinkles and folds. Finely tuned optics, enough cool down time and waiting for pristine moments of atmospheric conditions will help to reveal details such as these . Excited at seeing this type of detail at 120x magnification, I went inside and brought out a notepad to sketch the features I could make out.
Not every night do I get to view something that I have wanted to see since childhood. Reading books and seeing videos of the Great Red Spot when I was a kid always made me want to view it. Even if it does appear smaller with less detail and color, nothing can replace the feeling of excitement in knowing that you have viewed the largest storm in the solar system with your own eyes.
Star Log: July 15, 2010