Jim Bell, Cornell University

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This page contains a compendium of CCD photographs and drawings obtained in response to the possible Mars dust storm reported from microwave observations by Todd Clancy and colleagues in January 1996.


Posting: January 28, 1996
The two drawings below were made by amateur astronomer Ted Stryk of Tennessee between 20:00 and 20:45 UT on 1996 January 15 and between 20:50 and 21:00 on January 20 using the 6 inch apochromatic refractor at Bays Mountain Observatory in Kingsport, TN (+36 1/2 degrees).

  • JAN15TS.GIF

    Ted writes that "Seeing was not the best, around 5 on a scale of 1 to 10. The mountain was somwhat hazy, hurting contrast. Mars did offer some steady moments, during which I could just make out the dark albedo features in the southern hemisphere, just as Mars normally appears when it is distant, with no hint of obscuration. However, in red light the preceding limb appeared unusually bright. This could be due to a dusty haze. I can not say for sure whether or not there is a large scale dust storm on Mars right now, but the southern albedo features are not significantly obscured if there is one at this time. I couldn't tell if the red brightening on the limb extended on to the disk."

  • JAN20TS.GIF

    Of the second image, Ted writes: "Well, I got another observation in, though the view was not nearly as good as the last one. The sun problem is so bad that despite steady skies, Mars was hard to observe. I question wether I'll be able to find it again. I observed it today between 20:50 and 21:00 UT (such a short time since it took all my time just to find the planet). The image was steady but contrast was poor, and like last time, the dark south of Mars was obvious, but nothing else. If there was a bright limb in red like last time, the contrast was so bad that I probably would have missed it. I didn't see Mare Acidalium, which should have been in view, though this is most likely due to the poor contrast due to the sun and not dust. I will probably attempt one more drawing when the Syrtis Major side is visible just to see if anything looks obscured."


    Posting: January 13, 1996
    The following images were obtained by ALPO Mars recorders Dr. Donald Parker and Carlos Hernandez in Coral Gables, FL, on 10 January 1996. More Spectacular stuff!

  • jan-10.gif


    The above sequences were obtained on UT 10 Jan 1996 in an attempt to try to confirm the microwave observations of Todd Clancy that indicate a possible global dust storm. Mars was only 12 degrees from the Sun and only 4 arcsec in apparent diameter (!!), yet Parker and Hernandez were clearly able to resolve features on the disk.

    The top row of images are the data, massaged through some filtering to bring out details. The bottom row shows a representation of the Viking IRTM albedo map projected at approximately the same geometry as the Parker and Hernandez observations. It is included to help convince you that the features that are seen in the top images are in fact related to Mars surface albedo features.

    Here is what Don wrote about these images:

    In response to the dust storm alert of 5 January, Carlos Hernandez and I made visual red-light observations of Mars on 9 and 10 Jan UT dates. The observations covered the CM range from 95 to 165 degrees. While no great amount of detail was detected, we did independently see the southern maria fairly well. In addition, there was possibly some brightening over Tempe and Candor and Xanthe when these were near the pm limb. Yesterday, 10 January, we obtained a number of CCD images, all taken through a sharp cut on (630 nm) red filter, equivalent to the Wratten 29. The CM's ranges from 138-148 degrees. These images reveal "normal" appearing features in the south, such as Aonius Sinus, M. Sirenum, and M. Cimmerium. The "Chevron" of Titanum S. was imaged and was seen visually. Since the "dull side" of Mars was presented to us, no detail was seen in the north. However, from our observations, it is unlikely that a massive global storm exists at these longitudes. We will continue observations over the next week if possible, or until the prominences interfere...

    Last Modified by Jim Bell on 29 January 1996.
    Mail to: jimbo@cuspif.tn.cornell.edu