Astrophysicists at the Massachusetts Institute of Technology have captured footage of Pluto's moon, Charon, blotting out the light from a single star.

The event has only been observed once before, 25 years ago, and then with a single telescope. This time, the researchers trained four telescopes in Chile on the occultation, to capture as much detail as possible including a measure of the roundness of the moon, and its radius.

The data could also reveal whether or not the moon has an atmosphere. Although Charon is very small, and would not have much gravity to hold on to an atmosphere, it is so far from the sun and so cold that the researchers speculate some gases could yet be retained.

"We have been waiting many years for this opportunity. Watching Charon approach the star and then snuff it out was spectacular," said James Elliot, a professor in the Department of Earth, Atmospheric and Planetary Science and the Department of Physics at MIT.

You can check out the footage here. The movie is in QuickTime format. ®

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