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[Music throughout] A coronagraph is a way to see distant

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planets hidden by the glare of the star they orbit.

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The coronagraph reduces the light coming directly from the star to separate it from

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the light reflected by the planet. The Nancy Grace Roman Space

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Telescope's coronagraph doesn’t block the star’s light with an opaque disk

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as a simple coronagraph might. Instead, it uses

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a combination of disks with complex patterns and light-blocking stops

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to create destructive interference with the star’s light,

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effectively making it disappear, while allowing the light from planets to pass through.

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A complicating factor is that the light picks up small

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distortions as it reflects off the telescope’s series of mirrors, and

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these distortions can reduce the effectiveness of the destructive interference.

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Collecting more light increases the image signal, but the planets are still

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hidden under blobs of leftover distorted starlight. To

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remove these blobs, the coronagraph has special deformable mirrors that

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can change shape by using hundreds of tiny pistons. This corrects

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distortions in the light beam. As the mirrors deform, the

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blobs of light slowly begin to disappear, revealing brighter planets.

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Further adjustment brings fainter planets into view.

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Advanced software processes this data, further improving the

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contrast and clarity of the image. This processing makes

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objects more than a billion times fainter than the star visible.

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As a result, the Roman Space Telescope will provide the first look at

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individual planets in star systems that might be similar to our own.

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[Explore: Solar system & beyond]

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[NASA]