ISS and the Crescent Moon


On Friday, Feb 4, the International Space Station transited the crescent moon as seen in the eastern half of San Mateo county.  The event was expected to happen early in the evening and while not as bright as the ISS can get, it would be plenty bright to see in city lights.

I did some quick figuring and decided that I could get this event without having to move a tripod from the back yard.  How lucky!

Once I got home from work, I put the Stellarvue SV4 on the G11 mount, reconnected the 12V, and powered up for the first time since late 2020.

Of course, finding focus after removing the QSI camera was a slight challenge.  The crescent moon was visible in the afternoon sky, making the job much easier.  The feathertouch focuser was complaining about not having enough steps to reach the proper distance which required some additional fiddling.

Connected the ZWO 178C camera and was pleased that the focal length was ideal to image the entire moon plus extra space for the ISS approach.  

Once set up, it was time to wait for the event itself.  I put a timer on my phone and did the rest of the evening's activities.

At 7 pm, I returned outside, recentered the telescope on the moon, refocused, and watched for the proper timing.  I did a few test runs of Firecapture to ensure that the shots looked good.  The system was able to save the video at 17 frames per second.  

While waiting I watched what looked like a small airplane gliding towards the moon, I thought, this might be a good practice shot!  Started the capture and it went well.  It was only after the light passed the moon that I realized I'd just seen the event I was expecting!

Later in the evening, I exported just the frames of the event and made an animated Gif.


And a Youtube video:






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