Thierry Legault Meets His Own Challenge: Image an ISS Transit of a Solar Prominence

When you’re Thierry Legault and you want to challenge yourself, the bar is set pretty high.

“This is a challenge I imagined some time ago,” Legault told Universe Today via email, “but I needed all the right conditions.”

The challenge? Capture a transit of the International Space Station of not just the Sun — which he’s done dozens of times — but in front of a solar prominence.

Legault said the transit of the prominence, which he captured on August 21, 2015, lasted 0.8 seconds. His camera was running at 40 frames per second, and he got about 32 shots in that time.

See a video of the transit in real time, and more, below:

We’ve described in our previous articles how Legault determines the exact location where he needs to be to capture the images he wants by considering the width of the visibility path, and trying to be as close to the center of the path as possible. But this challenge was a bit different.

“I took the last transit data from Calsky, the real position of the prominences, and made angles and distances calculations to place my telescope this time not on the central line of the transit but 1 mile north from it,” Legault said, “to have the ISS passing in front of the largest prominence.”

You can see some of Legault’s stunning and sometimes ground-breaking astrophotography here on Universe Today, such as images of the space shuttle or International Space Station crossing the Sun or Moon, or views of spy satellites in orbit.

If you want to try and master the art of astrophotography, you can learn from Legault by reading his book, “Astrophotography,” which is available on Amazon in a large format book or as a Kindle edition for those who might like to have a lit version while out in the field. It is also available at book retailers like Barnes and Noble and Shop Indie bookstores, or from the publisher, Rocky Nook, here.

For additional imagery and information, visit Legualt’s website.