Deimos & Mars

June 17th 2001

Deimos moves along its orbit on June 17th 2001. Mars is heavily over-exposed taken at f/18 on a 60cm Cassegrain telescope using an Astrovid 2000 camera. (No occulting disc) Utilizing COAA's AstroVideo software each image is a composite of 150 accumulated real-time video images.

Then equally stretching each resulting image to reveal the subtle presence of Deimos I cropped the frames. Although the COAA software is specifically aimed at deepsky imaging with unintensified video cameras coupled to fast scopes, I was interested in trying the software on the 60cm telescope if a suitable opportunity arose.

Confident I had plenty of good Mars images on tape and disk nearing the end of my run I decided to mount an Astrovid 2000 camera at the telescopes focus with its shutter speed set at 1/25 of a second and maximum signal gain output. The view on the monitor was of course quite noisy however even with the added viewing difficulty of the nearby over saturated glare from of Mars I could just make out what seemed to be an extremely faint star or satellite flickering in and out of view but not always directly. I seized this opportunity to try out the software in order to smooth out the noise and enhance the faint light source.

The final image produced by the software revealed that this flickering point of light was indeed something moving roughly along the plane of Mars' equator. Later stretching the brightness levels further in PhotoShop a checkerboard pattern became apparent (something to do with how the software processes the images). To confirm its identity I took images roughly 10 minutes apart. Later checks using Guide software revealed it was mag 12.6 Deimos. Phobos was in mid transit across the disc of Mars.

I would encourage others with a capture card interface to give this software a try if you haven't already. Although extremely pleased with the images of Mars obtained this year and the performance of the freshly aluminized primary mirror, capturing Deimos was certainly a bonus.