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.

December 5, 1997
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Seeing Through Galaxies
Credit: R. White, W. Keel (U. Alabama), C. Conselice (U. Chicago)

Explanation: In this dramatic picture, spiral galaxy NGC 5091 appears in the foreground. Tilted nearly edge-on, the dust lanes between its spiral arms are clearly visible. The large elliptical galaxy NGC 5090 lies just beyond it - both are about 100 million light years distant in the southern constellation Centaurus. Can you see through the spiral galaxy? The detailed answer to this question has important implications for determining the nature of dark matter and the measurement of star formation rates. Comparing the overlapping and non-overlapping parts of this and other pairs of galaxies offers a neat way to find the answer.

Tomorrow's picture: A Quasar Portrait Gallery

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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