Comet 103P/Hartley Faint comet in Lacerta

Uploaded 9/5/10

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 Screaming across the fall sky, this periodic comet will be making its closest approach to the Earth in centuries in a few months at a minimum distance of 11 million miles. It is currently 32 million miles from earth and closing fast. Even now, this very faint 11.5 magnitude object shows photographic green coloration promising more dramatic gas activity in the months to come! Visually, this object was just barely visible in the 8" at 50x, and no hint of the short fan like tail near the core you see here was evident.

The field of this image is 2.5 degrees, or 5 full moons wide. The comet is already gaining considerable size and should put on a fine show when it swings over to Cassiopeia and onto Auriga in the coming months. For this image, the one hour exposure was stacked by summing such that the nucleus of the comet was in register to track the motion of the comet against the background stars. The stars appear as streaks whizzing by, and this will only accelerate greatly as the comet gets closer. The comet will then be a blur in a short 5 minute sub frame! Ah, the challenges of a comet imager...

Optics: 8" f/4 Newtonian Astrograph w/Baader MPCC Coma Corrector Platform: Astrophysics AP1200 Camera: Hutech Modified Canon XTi @ ISO800 Exposure: 12 x 5m = 1 hour Location: Payson, Arizona Elevation: 5150 ft. Sky: Seeing 7/10, Transparency 9/10 Outside Temperature: 75F Processing Tools: Photoshop CS2, Images Plus 3.82 HOME GALAXIES EMISSION NEBS REFLECTION NEBS COMETS GLOBULARS OPEN CLUST PLANETARIES LINKS