ISS and Atlantis seen in broad daylight!

Contributed by
Jul 18, 2011
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This is pretty amazing: on Sunday, July 17, amateur astronomer Scott Ferguson was able to get video of the Orbiter Atlantis docked to the International Space Station when they passed overhead in broad daylight!

How cool is that?

This looks legit to me. This video was taken about 1.25 hours after the Sun rose! Atlantis is the glowing white object at the top of the ISS. You can clearly see the solar panels on the station, and get a hint of other structures too. The two dark donuts are dust motes on the camera detector; they are out of focus and optical effects make them look like rings -- you see these a lot in astrophotography, but they're generally not noticed because the background is dark. In this case, the morning sky makes them more obvious.

Ferguson used a 20 cm (8 inch) telescope and a video camera optimized for astrophotography. He also used software that predicted the position and path of the two orbiting spacecraft; though the ISS can get about as bright as Venus, it's very hard to see during the day, so having a solid prediction was critical. He used guiding software which he had to assist by hand, which is remarkable. As he told me, he was hoping to get a night-time pass, but there weren't any at his location. Rather than give up, he saw an early morning pass, so gave it a shot... and wound up with this astonishing footage.

It's funny to think of how much detail you can see, but when it passes overhead the ISS is only 350 km (210 miles) or so above you (and even when it's halfway up the sky it's only about 150 km farther away). And since it's 100 meters across, it actually can be easily resolved by binoculars! You won't see much, but it will clearly be an extended object, and not just a dot. Through a telescope, well, you can see that for yourself.

This is quite an accomplishment, and I'm glad someone was able to do it in the final days of the Orbiter's mission. I was actually hoping we'd see something spectacular from this last hurrah, and yeah, I think this qualifies.

Related posts:

- Seriously jaw-dropping pictures of Endeavour and the ISS
- Discovery spacewalk seen from the ground!
- Discovery's last moment in the Sun
- Atlantis goes head over heels