I managed to resolve the ISS "H" with naked eye on a recent pass!


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Mar 8, 2010
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I just wanted to share something really cool because I like to test the limits of my vision with astronomical objects. For instance I have tried for decades to try to resolve at least one moon of Jupiter with my naked eye at opposition. It just isn't possible for me, but Jupiter does go from a point source of light to a tiny "smudge" at opposition and depending on what side of Jupiter Ganymede and Callisto are on can change the shape of the tiny smudge of light giving it a bulge. So while I cannot resolve any moons, if conditions are right I can spot the glow of multiple moons together on the same side of Jupiter.

So I have my email set I get alerts about the ISS passing overhead. I've watched it dozens of times but this one was a little different in that when I checked the orbit track, it was due to literally fly right over my head that night.

So I go out at the appropriate time with my sister and her husband to watch it fly over and I see it appear in the west and lazily make its way closer to me, growing brighter and brighter and brighter. Then when it was almost to the zenith, just for a few seconds, it went from being a dot to the familiar H shape that I have seen tons of times through binoculars. Then faded back into a dot as fast as it had resolved itself.

My mouth dropped because I didn't think it was at all possible to resolve the H shape of the ISS with the naked eye, but I managed it for the briefest of moments, it was pretty cool.

Now surely some of this is simply that looking through telescopes and binoculars has trained me to use my peripheral vision to look at dim objects but that is still pretty amazing that the Mk I Mod 0 Eyeball can see.

You guys ever have moments like that at the telescope or naked eye observing and just catch details that shift into focus and out quickly?