April 30, 2008
Our listeners ask: Will the sun ever burn itself out?
BOB HIRSHON (host):
The sun’s expiration date. I’m Bob Hirshon and this is Science Update.
Students in Jenneva Schumacher’s 8th grade class at North Royalton Middle School in Ohio wrote to ask whether the sun will ever burn itself out. We turned to Terry Kucera, a solar physicist at NASA’s Goddard Spaceflight Center in Greenbelt, Maryland.
TERRY KUCERA (NASA Goddard Spaceflight Center):
The sun will eventually burn out. It’ll put on a really big show before that though.
After it uses up all the hydrogen in its core, it will start to burn the outer shell.
We expect in about 7 billion years, the sun will have become a red giant star.
This will cause it to expand and possibly even burn up the earth. After that, it will start burning helium, shrink, and then expand again. Eventually, it will lose its outer atmosphere and shrink into a white dwarf, slowly fading out. I’m Bob Hirshon for AAAS, the Science society.