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 6, 1997

Blue Sun Glaring
Credit: EIT, SOHO, ESA, NASA

Explanation: The Sun is a bubbling ball of extremely hot gas. In this false-colour picture, light blue regions are extremely hot - over 1 million degrees, while dark blue regions are slightly cooler. The camera filter used was highly sensitive to the emission of highly charged iron ions, which trace the magnetic field of the Sun. The rich structure of the image shows the great complexity of the Sun's inner corona. A small active region can be seen just to the right and above centre. This picture was taken in ultraviolet (extremely blue) light by the Extreme-ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO) spacecraft, which is orbiting the Sun just ahead of the Earth, at the L1 point. SOHO was launched in 1995 and will continually monitor the Sun for several years.

Tomorrow's picture: Red Sun Streaming


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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.