On Wednesday night, stargazers lined up at Northwestern’s Dearborn Observatory hoping to catch a glimpse of a lunar eclipse – an astronomical event that has inspired awe throughout recorded history.
The observatory was open between 8 p.m. and 10 p.m. to all people interested in viewing the event, and by 9 p.m., the line was out the door.
“There’s nothing particularly special about (a lunar eclipse), but the alignment has to be just right,” said Michael Smutko, a senior lecturer of physics and astronomy at NU and astronomer at Adler Planetarium.
A lunar eclipse occurs when the moon passes through the shadow of the Earth, which happens on a regular basis, he said.
The eclipses are predictable, but the time spacing between lunar eclipses is irregular because the orbits of moons and planets are ellipses, not circles, Smutko said. Lunar eclipses can be predicted years in advance down to a fraction of a second. He added that the Inca, Greeks and other ancient cultures used them to learn about the universe.
“Today, they’re mostly just a fun event to watch,” he said.
According to NASA’s Web site, the moon was in totality – when the Earth’s shadow completely covers the moon – for 50 minutes. During an eclipse, the moon changes color from grey to red or orange.
The last lunar eclipse visible from the Chicago area occurred in August 2007, and the next will not happen until December 2010.
Observatory events can sometimes draw crowds, but the weather can be a determining factor of both visibility and turnout, Smutko said. He described Wednesday’s eclipse as a “prime time” event.
The observatory is open every Friday between 8 p.m. and 10 p.m.
“Sometimes people ask us: ‘Why don’t you get a new (telescope)?'” he said. “This thing is so old. But it’s the same reason why you wouldn’t replace a Stradivarius with something from Yamaha … it is a classic instrument.”
