INSANELY awesome solar eclipse picture | Bad Astronomy

04 Jan

Earlier today Europe, Asia, and Africa got to see a nice partial solar eclipse as the Moon passed in front of the Sun, blocking as much as 85% of the solar surface. The extraordinarily talented astrophotographer Thierry Legault traveled from his native France to the Sultanate of Oman to take pictures of the eclipse. Why there, of all places? Heh heh heh. It’ll be more clear when you see this ridiculously awesome picture he took:

Holy solar transits! Click to embiggen, which you really really should do.

Can you see why he traveled so far to get this shot? The silhouette of the Moon taking a dark bite out of the Sun is obvious enough, as are some interesting sunspots on the Sun’s face… but wait a sec… that one spot isn’t a spot at all, it’s the International Space Station! This was a double eclipse!

That’s why Thierry sojourned to Oman; due to the geometry of the ISS orbit, it was from there that he had the best chance of getting a picture of the station as it passed in front of the Sun during the relatively brief duration of the actual solar eclipse. But talk about brief; the ISS was in front of the Sun for less than second, so not only did he have one chance at getting this spectacular once-in-a-lifetime shot, but he had only a fraction of a second to snap it!

To give you an overall idea of what you’re seeing here: the Sun is 147 million kilometers away (less than usual because this eclipse happened, coincidentally, very close to perihelion, when Earth was closest to the Sun). The Moon is 390,000 kilometers away. The Sun is about 400 times bigger than the Moon, but also about 400 times farther away, making them look about the same size in the sky. If you’re still having a hard time picturing the scale, take a look at the dark sunspot in the lower right of the big picture: it’s about twice the size of the Earth!

The space station, on the other hand, is 100 meters across (the size of a football field) and orbits about 350 km (210 miles) above the Earth’s surface. So the Moon was very roughly 1000 times farther away than the ISS when this picture was taken, and the Sun 400,000 times more distant. Yet all three lined up just right to make this extraordinary photograph possible.

Thierry has taken some of the most amazing pictures of the station passing in front of the Sun and Moon I’ve ever seen — his shot of the ISS and the Moon shortly before last week’s lunar eclipse was beautiful — but this one really stands out. It took an extraordinary amount of planning, scheduling, travel, and plain old good thinking to make this picture happen. Congratulations to him for getting it, and I thank him for sending it to me!

[More eclipse pictures can be found linked from Stuart's Astronomy Blog as well as on the BBC's Sky at Night Flickr pool of pictures.]

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- When natural and artificial moons align
- ISS, Shuttle transit the Sun
- Check. This. Out. Amazing photo of the Sun!
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