TOP 10 THINGS YOU DIDN'T KNOW ABOUT ANTIMATTER

Reaching For The Stars

antimatter anti matter galaxy star milky way

Is this galaxy made of regular matter, or antimatter? We may never be entirely certain one way or the other. Credit: NASA/Goddard Space Flight Center

1. Antimatter Stars and Galaxies

We may not fully understand the reasons for a universe lopsided in favor of regular ol' matter, but it's the reason matter won out at the dawn of time -- and antimatter was reduced to its current, meager role in the observable universe.

But this mystery begs the question: Could there be whole stars out there somewhere composed of antimatter? Or even a galaxy in which anti-atoms are the status quo?

An antimatter star may not differ that much from a typical star. Its light would be indistinguishable as the same physical properties apply -- it's merely the material involved that is different. Of course, a theoretical anti-sun would have to exist beyond the reach of matter -- as in, it would have had to have survived all the collisions and mingling of dusts and bodies that birthed the observable universe. Likewise, an antimatter galaxy would have to exist far from those composed of regular matter.

When you get right down to it, the Milky Way is the only galaxy we're 100 percent certain is made of matter! The chance is extraordinarily slim, but any of the 2 million galactic superclusters out there could be pure antimatter. The light that reaches our little world would be indistinguishable, either way.

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