The glowing arch of the Milky Way is a beautiful sight -- but sometimes it gets in the way of other cosmic beauties. That's the case for two nearby galaxies in Cassiopeia, a W-shaped constellation that soars high overhead on November evenings.
In 1968, Italian astronomer Paolo Maffei was studying young stars in Cassiopeia. He noticed two fuzzy blobs in his pictures. He didn't know what they were, but two years later other astronomers concluded that both were nearby galaxies.
Now named Maffei 1 and 2, the galaxies are only 10 million light-years away -- quite close on the galactic distance scale.
Maffei 1 is a giant elliptical galaxy, so it looks like a fat, fuzzy football. Maffei 2 is a giant spiral galaxy, like our own Milky Way.
Because they're so close, Maffei 1 and Maffei 2 should be two of the brightest galaxies in the sky. But something else is in the way: the Milky Way.
The stars of Cassiopeia are all in the Milky Way, so they're between us and the more-distant galaxies. Worse, the constellation also contains lots of gas and dust, which block all but about one percent of the galaxies' visible light. So even though they're close and bright, the two galaxies were discovered just 40 years ago.
But infrared energy does penetrate the gas and dust. So in recent years, astronomers have used infrared data to learn more about both galaxies -- two hidden giants, lurking close to the Milky Way.
Script by Ken Croswell, Copyright 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine.
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