By
Sara Bruestle
April 4, 2008
I am an amateur stargazer.
I can usually point out the Big Dipper, and sometimes I’ll find Cassiopeia or Orion. Maybe I’ll manage to spot Polaris and the Little Dipper, but that’s about it as far as stars and constellations go.
Often I’ve looked up at the night sky and wished I could play connect-the-dots with the stars, but couldn’t. I’m sure others have felt the same way.
I turned to the Department of Astronomy at the UW to answer questions a beginner stargazer might ask. Namely, what does a stargazer need to observe the night sky?
Ana Larson, a UW senior lecturer of astronomy, said the most important thing amateur stargazers need, in order to get the most out of their stargazing experience, is a desire to look at and learn about the stars.
“[They need] wonderment, desire to learn more about what they’re looking at — an interest to find out what all [is] out there instead of just white twinkly things,” Larson said. “They’ve got to ask themselves questions: Why are some stars brighter? Why are some stars different colors? Why do stars die out? Why are they born?”
Larson recommends stargazers get a star map or a star finder.
“Take it with [you] at night, and then dial up what to look for in the sky,” she said.
Stargazers will also need to bring a flashlight. However, the flashlight should be dim or red. Bright, white light will ruin the eyes’ sensitivity to light and make it harder to see stars. StarDate Online, a stargazing Web site provided by the University of Texas McDonald Observatory, suggests taping red cellophane over a flashlight.
Stargazers will also need to go to a site that has a clear view of the sky, away from city lights. Larson said the closest, easiest and darkest place is Rattlesnake Lake, just south of North Bend, Wash. She said the view from the parking lot works fine.
“[Go] whenever it’s clear,” she said. “We have so few clear nights that you really want to get out there any time you can in the year.”
Larson also recommends bringing a pair of binoculars, for those who wish to see farther than the naked eye. She said a high-power pair of binoculars isn’t necessary, nor is a telescope.
“It’s a costly investment,” she said.
Even when equipped with all stargazing necessities, an amateur stargazer still needs guidance on how to make the most of a starry night.
What other stargazing tips should stargazers follow?
Matt Davis, a UW astronomy graduate student, said it’s important for a stargazer using a star map or a star chart to determine which way is north and to get oriented with the night sky.
“The best way to do that is to find Polaris, the North Star,” he said.
Davis said the easiest way to find the North Star is to first find the Big Dipper, which isn’t really a constellation but an asterism, an easily identified grouping of stars not included in the 88 constellations officially recognized by astronomers. Draw an imaginary line from the two stars that make up the edge of its bowl, called the pointers, because they roughly point to the North Star. An added bonus, the North Star is the tip of the handle to another asterism called the Little Dipper.
Not only does the Big Dipper make spotting the North Star easier, it also acts as a signpost to other asterisms and stars. Stargazers should try visually extending the arc formed by the stars of the handle of the Big Dipper to find the orange star Arcturus in the constellation Boötes, according to the textbook Pathways to Astronomy.
Davis also suggests stargazers use their hands to measure distances to get a better idea of the location of stars and constellations.
“The sky is broken up into degrees, so if you want to measure how many degrees something is from the horizon, you can either use a fancy instrument or you can use your fists,” he said. “There are a bunch of different tools you can use; your hand spread at arm’s length covers an angular size of about 20 degrees, your fist is about 10 degrees, your thumbnail is about two degrees and your pinky fingernail is about one degree.”
Stargazers can also use the hand-measuring method to find the latitude, he added.
“If you want to know your latitude, go outside, find the North Star and find a way to measure how far the North Star is away from the horizon — [that’s] your latitude,” Davis said. “Just start stacking fists.”
Should stargazers have any difficulties seeing a faint star, Davis advises them to use their peripheral vision to look at the star instead of looking directly at it.
“When you look straight at something you’re using the color-sensitive parts of your eye,” he said. “At night you start to lose the ability to see colors. At night everything looks gray, so we sort of switch to using the light-sensitive parts of our eyes. Your peripheral vision is most sensitive to light and dark.”
What about meteor showers?
Phil Rosenfield, another UW astronomy graduate student, has a line of advice for stargazers who have never watched a meteor shower: Don’t set your hopes up too high.
“Meteor showers are hard to catch,” Rosenfield said. “They are hit-and-miss. Stargazers new to meteor showers can be let down, because they expect to see something amazing but then only see two or three [meteors].”
But that doesn’t mean meteors are impossible to spot.
“We’re constantly being bombarded by dust, by meteors,” Rosenfield said. “Sometimes I’ll see five in one night in a dark sky just while I’m walking around.”
Meteor showers are best seen between midnight and dawn, because that’s when the Earth is rotating directly into the oncoming stream of debris, according to a science editorial on msnbc.com. The best time to look for “Earthgrazers” — seldom spotted but long-lasting meteor showers that the article reported appear near the horizon — is between sunset and midnight. Another bonus is that meteor counts tend to rise as the night wears on.
But even after taking into account all these recommendations, how should an amateur stargazer go about stargazing?
“Actually, what I do is what so many astronomers do: I just look up and see what’s around,” Larson said. “It’s comforting to me to know that the stars are still out there. I can always just look up at the stars.”
[Reach reporter Sara Bruestle at features@thedaily.washington.edu.]
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