People near Iowa City planning to watch tonight’s super-lunar eclipse, are invited to the roof of Van Allen Hall at the University of Iowa. A group of UI astronomers is holding a public viewing of the phenomena which occurs once perhaps only two or three decades.
Like a lunar eclipse, a super-lunar eclipse occurs when the earth is between the sun and a full moon, with the moon completely covered by the earth’s umbra, or shadow. What makes a super-lunar lunar eclipse so rare, is that the eclipse coincides with when the moon is at perigee, its closest point to earth.
"It's interesting because you'll see the earth is round, you can see the curvature of the earth right on that shadow," says UI astronomer Robert Mutel. "It will be a very, very distinctly coppery or reddish-orange-reddish color."
The coloring is due to the fact the earth's shadow isn't black, but rather reddish. Sunlight scattered through the earth's atmosphere creates the unique color. In addition to coppery-red, the moon will also appear about 25 percent brighter and 14 percent larger than normal due to it's proximity to earth.
The last time a super-lunar eclipse occurred was in 1982. Astronomers say earth won't see another for 18 years.
The Ames Area Amateur Astronomers is having a Blood Moon Lunar Eclipse Party at the observatory in McFarland Park. The Drake Municipal Observatory and the Eastern Iowa Observatory and Learning Center will also be open for those wanting a clearer view of the eclipse.
The eclipse should start around 8:10 p.m. central time Sunday.