More Axions

StarDate: May 22, 2009

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialize correctly.

audio/mpeg icon

The particles known as axions are enigmatic.

Massive amounts of them may have been created in the Big Bang. They may outweigh all other forms of matter in the universe. And trillions of them may zip through your body every second. Yet no one has ever seen one -- and they may not even exist. But their discovery would go a long way to confirming that axions make up most of the matter in the universe -- the mysterious dark matter.

Dark matter produces no detectable energy, but it exerts a gravitational pull on the visible matter around it. There seems to be several times more dark matter than normal matter.

Texas astronomer Don Winget is leading a team that's looking for evidence of axions in white dwarfs -- the hot, dense "corpses" of stars that were once like the Sun.

Many of these stars "tick" like a finely tuned clock -- any change is caused by a change in the star itself.

Theory says that axions are created deep inside these stars, then zip out into space. As they do so, they carry away energy, causing the star to cool and its ticking to slow down.

So the Texas astronomers are carefully timing changes in these stars. They'll compare what they see with models of how the timing should change if the stars are producing axions. If the "ticking" slows down by the right amount, it means the stars are producing axions -- and the mystery of dark matter will be closer to a solution.

Script by Damond Benningfield, Copyright 2009

For more skywatching tips, astronomy news, and much more, read StarDate magazine.

The one constant in the Universe: StarDate magazine


©2014 The University of Texas McDonald Observatory