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.

July 9, 1996

M74: A Grand Design Spiral Galaxy
Credit: NASA, UIT

Explanation: M74 is about the same size as our own Milky Way Galaxy. Like our Milky Way, M74 is classified a spiral galaxy. M74's sweeping lanes of stars and dust combined with its small nucleus make it a classic Grand Design Spiral. On the Hubble Sequence of Galaxies, M74 is listed as "Sc". In the above picture, visible light is shown in red and ultraviolet light superposed in blue. In general, older stars are more red and younger stars are blue. Studies with the Ultraviolet Imaging Telescope show that the disk of M74 has undergone significant star formation in just the past 500 million years.

Tomorrow's picture: Galileo Photographs Ganymede

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