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.

2002 June 3
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Galaxy NGC 4388 Expels Huge Gas Cloud
Credit & Copyright: Suprime-Cam, Subaru Telescope, NAOJ

Explanation: Why are huge clouds of gas billowing from spiral galaxy NGC 4388? The extent of the gas clouds, over 100,000 light-years, was unexpected before the Subaru Telescope took the above image. NGC 4388 has a bright energetic nucleus and so is classified as an active galaxy. The spiral, relatively close by at 60 million light years, is a member of the nearest major cluster of galaxies: the Virgo Cluster. One hypothesis holds that the gas was stripped away as NGC 4388 made its way through the intergalactic medium of the Virgo Cluster. A competing hypothesis holds that the gas is all that remains of a smaller galaxy that was gravitationally deconstructed by the larger NGC 4388. Further observations may better determine NGC 4388's past and likely contribute to a better understanding of how galaxies evolve inside massive clusters.

Tomorrow's picture: A Martian Metamorphosis

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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.