Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

January 20, 1999
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Possible Planets And Infrared Dust
Credit: Left- A. Weinberger, E. Becklin (UCLA), G. Schneider (U. Arizona), NASA
Right- B. Smith (U. Hawaii), Glenn Schneider (U. Arizona), NASA

Explanation: These near-infrared Hubble images of dust surrounding young stars offer the latest tantalizing evidence for planets beyond our Solar System. At left, the dark gap seen in the dust disk is reminiscent of a similar large gap in Saturn's rings believed to be sculpted by orbiting moons. By analogy, the gap in the dust disk of HD 141569 may be a larger scale result of unseen orbiting planets. At right is a relatively thin stellar dust ring suggestive of planetary rings held in place by orbiting moons. On a much larger scale this ring around the star HR 4796A could also indicate the presence of orbiting planet-sized bodies too faint to be directly visible. For a distance comparison, the orbit of Neptune is drawn at the lower right of each picture. The overwhelmingly bright starlight at the center has been blocked out to reveal the dim dust features.

Tomorrow's picture: Wide Field

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.