Sunday, 16 September 2012

A new astrophotography challenge

Taken through the 20 inch scope, the ISS (space station) passed first 350 miles from the observatory, then went round the earth and passed 1000 miles from the observatory then faded into the earth's shadow (night). I had to chase it, but I got pics both times round with my Canon. I made them into this mosaic that puts the images much closer together The second time round (bottom), it was at a lower altitude in the sky. It moves at something like 20000 mph! I'm well chuffed just seeing some detail. I guessed an exposure of 1/800" at ISO 1600. Apparently the software we have can be programmed for tracking satellites. Next time the ISS shows its face in the evening, I'd like to give imaging it a proper go. The tracking accuracy involved in getting the ISS on our Imaging source camera's tiny chip with a barlow lens might well out stretch our capabilities.

Season two of the galaxies

In autumn, our planet's orbit takes us into such a position that looking away from the sun is out of the plane of the Milky Way. Spring is the best galaxy season, but season 2 of the galaxies is autumn, when we look out toward the galactic south. The milky way appears to roll around from South-North to East-West for northern hemisphere observers. In this vast blackness, in the constellation Pegasus are galaxies NGC 7479 and NGC 7814. The former is located below the bottom right star of the Square of Pegasus and the latter just inside the Square's lower left corner star. 7479 has amazingly wide spiral arms, and 7814 is as exact and edge on view as I've seen, but it was not possible to see the division visually in the 20" scope. For 7479 I stacked 35 30 second shots and for 7814 I stacked 14.

Palomar 8

Palomar 8 is a globular cluster orbiting our galaxy that we see as its passing through the galactic plane. This means it has lots of dust in the way and consequently its light is quite attenuated. I was browsing through Sagittarius with the 20" telescope and just hopped a bit to the left of open cluster M25 and got a few images of this faint globular.