Geostationary Satellite Eclipse - XM-3 and XM-5

For a few weeks around the equinox all geostationary satellites will briefly dip into the shadow of the Earth for around an hour each night. I usually try to photograph this event, but this is my first attempt to watch two satellites with my planetary camera. The benefit of this camera is that it runs on my laptop, so I don’t have to worry about my DSLR running out of batteries or having a remote shutter. The downfall is that this camera has a very high zoom level, which makes it hard to see multiple satellites in a single frame. Thankfully XM-3 and XM-5 are very close together and I could get them in a frame together.

Even though this was supposedly a simpler setup than previous images I had a horrible string of bad luck. The first night I had perfect weather, but a Windows update rebooted my machine in the middle of the night and I missed the eclipse! Another night I set up but forgot to plug the laptop in, so it ran out of batteries before it could catch the eclipse. After nearly a week I FINALLY had a fully clear night that recorded good images the entire time.

I used my 8” dobsonian telescope, ZWO ASI290MC planetary camera, and a new 0.5x focal reducer that I bought specifically for this image. Unfortunately I discovered that the focal reducer doesn’t actually fit the screw threads on my camera, so I had to get creative with duct tape.

It’s not pretty but it worked! Images were captured using FireCapture software where I used 5 second exposures and a gain of 300. Thankfully the Orion nebula went right by the XM-3 and XM-5 satellites each night, so pointing and focus was relatively simple.

Images were very lightly processed. I removed some hot pixels using a python script I wrote, and I did some slight level adjustments in DarkTable. Final annotations and video editing were done in VSDC Video Editor.

The first video is the satellite eclipse itself, around 1:30am EDT.

What surprised me about the entire night of images was that the satellites moved more than I was expecting. I then made a time lapse video of the entire night to watch them moving.

If you take this video a time lapse image you can see the full paths the satellites took, as well as a small gap from when they were in the shadow of the Earth. This picture is very busy, and hard to know what you’re looking at without any explanation, but I thought it was really interesting.

Eclipse season still has another week or two, but I think I’m done photographing these two for now. I’m looking forward to some warmer evenings, bring on Spring! Happy equinox!