STScI

ISS in front of the moon

You don’t always have to expose objects thousands of light years away for hours to see interesting objects or events in space – sometimes you can stay in the astronomical front yard, and observe very fast events. On the picture the ISS is to be seen – taken on 13 May at 23:21:31.12 o’clock. The precise time is due to the very short time span it took, only 0.93 seconds until the ISS has sped past in front of the moon from our point of view. Fortunately, with the help of the website transitfinder (https://transit-finder.com/) it is possible to predict precisely where and when such a transit can be observed.

The photo is composed of individual frames of a video, from each frame the ISS was cut out and inserted on a picture at exactly the same place again, so that a kind of trace shows up. On the basis of this path one can reconstruct, where the ISS flew exactly (as seen through our telescope). The photo of the moon was taken only a few minutes after the transit of the ISS, a compositing cannot be avoided because of the different camera settings needed to take either the moon or the ISS in front of the moon.

On the photo one can already see very nicely the characteristic shape of the ISS, left and right with the large solar panels and the habitat in the middle.

Photo and Text: Simon Gier

Add comment