YZ Canis Minoris
Procyon, the brightest star of Canis Minor, the little dog, trots high across the south this evening. It's one of the brightest stars in all the night sky. It's to the lower right of the Moon at nightfall, and tags along beside the Moon during the night.
Just to the south of Procyon is a star that's so faint you need a telescope to see it, but so cantankerous that astronomers have spent decades studying it.
The star is YZ Canis Minoris. It's just 19 light-years away. And like most of the stars in the galaxy, YZ Canis is a red dwarf -- a star that's much fainter, cooler, and smaller than the Sun.
What makes YZ Canis so interesting is that it spews large flares of radiation and charged particles into space. In fact, it's one of the most active red-dwarf flare stars in the galaxy.
Strong magnetic fields create the flares. The flares are so intense that they can outshine the rest of the star, sometimes more than doubling its brightness. And the flares are so frequent that astronomers often see several during a single night.
The flares produce not just visible light, but also deadly ultraviolet radiation and X-rays. If YZ Canis has planets, the radiation may pose a challenge for anything that lives there. Perhaps, when a flare erupts, life takes shelter in caves. Or maybe life resides beneath lakes and oceans. Or possibly, unlike life on Earth, living beings actually thrive in the radiation-strewn environment around YZ Canis Minoris.
Script by Ken Croswell, Copyright 2007
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