Thursday, 10 April 2008

Saturn again

Last night, I spent a long time trying images of Saturn. I've got a new motorised focuser, which finally means I can focus in an out with out any perceptible shake of the image. This makes it a little easier getting an image into focuser, although its still a lot of trial and error.

This is the best of the pictures from last night.

Tuesday, 8 April 2008

An iridium flare

Last night was a great night for observing orbital things, in theory. The space shuttle, a number of rocket bits and pieces and various other satellites were all scheduled to pass overhead.
However, that was the theory. In practice there was an awful lot of cloud about. None of that wispy mostly transparent stuff. No, this was thick piled up stuff as dense as you like. But - it wasn't wall to wall, at least not all the time.
Anyway - I went out to try and spot the ISS - although it was a bright pass, the time was not good, as the sky was still a faint bluey colour, the sun not having set very long ago. I could see a couple of the brighter stars after a while and the ISS should be magnitude -1.8 which is brighter than pretty much anything else in the sky other than the moon, but it wasn't looking good for the 3rd magnitude rocket bit that was coming over at the same time. I managed to spot the ISS eventually, but it wasn't the bright object it normally was.

I skipped most of the other passes as they were not very bright and with the large covering of cloud, would be difficult to spot. However there was an iridium flare scheduled for about 5 minutes to 10. The iridium satellites are a whole group of orbiting communication satellites, that have a highly polished panel attached, that if it happens to be in just the right orientation reflects the sun very brightly. There are programs to predict these events, I used the heavens above site.
I set up my point-and-shoot digital camera on video mode on a tripod pointing roughly in the right direction to try and spot it. I waited until about the right time, and then pressed the button and hoped that it was pointing about right, and that nasty bank of cloud would not obscure it.

What do you know, I saw it and caught it too!

It looks better at the original resolution, but you can see a bright dot at least. It is magnitude -7 or so, which is very bright indeed.

Tuesday, 1 April 2008


The ISS is being serviced by the ATV at the moment. They are in about the same orbit, but the ATV is just a little ahead of the ISS. The ISS is very visible at magnitude -2 or better, and the ATV is noticeable as it is leading the ISS. This particular ATV is the Jules Verne and is testing out various things.

Anyway, it was clear last night, but there was high level cloud which made everything a bit fuzzy, and the photos didn't show very much.

Tonight it was a much crisper night, and I tried taking the camera off manual and letting it take different length exposures based on the available light. They varied from about 5 seconds to 10 or 12. One of them actually caught both vehicles and showed them up quite nicely after a bit of rebalancing of levels. You can see the ISS as the main streak, and just to the top of the frame there is a thin streak from the ATV.

Also evident was about 3/4 of the way across the sky it went into shadow and started to fade, which is caught in the last one.