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Imagine That! -- "Extrasolar Camera"

Imagine That!
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Imagine That! -- "Extrasolar Camera"

Credit: NSF/Finger Lakes Productions International

Audio Transcript:

If you think digital cameras are cool, get ready for this! There's a camera that takes images of planets in other solar systems!

Imagine That!

This new camera is called the simultaneous differential imager, or SDI. And it's designed to take pictures of something no one's ever seen before: extrasolar planets--planets outside our solar system. Imagine looking at a firefly in front of a huge spotlight. It'd be pretty tough to pick out the little bugger with the much more intense light glaring from behind. Extrasolar planets are the fireflies, and behind them are their enormously bright parent stars, making them virtually invisible.

Up to now, researchers have only identified these planets through the tiny wobble they make in their parent star's orbit. But the SDI takes images using filters to examine the difference in methane content between the star and the planet. We'll let Laird Close, researcher at the University of Arizona explain:

Close: "If we take a picture in the two different filters at once, in both the images, the star looks equally bright. But in one image, the planet's very faint, and in the other image the planet's quite bright. So if we subtract the two images, the star will go away, and the planet will pop up."

Close says some early images have already forced scientists to re-examine their understanding of planets and the solar system. How's that for a big picture? I'm Eric Phillips.

"Imagine That!" covers projects funded by the U.S. government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at

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