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.

August 13, 1995

The Sun Flares
Credit: NASA, Skylab

Explanation: The sun was captured in 1973 throwing one of the largest flares ever recorded. Sol, our sun, is a normal star. It formed about 5 billion years ago, and will last about another 5 billion years. The sun will never explode, and a solar flare will never destroy the earth. Eventually the sun will become a white dwarf star. The sun is made of mostly hydrogen and helium. The sun's centre is so hot that when hydrogen nuclei collide, they stick together and release energy - a process called nuclear fusion No one knows why the centre of the sun emits so few neutrinos.

Tomorrow's picture: Mercury: Closest Planet to the Sun

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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.