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Finding your way around the southwestern Minnesota night sky can be really intimidating, especially if you're new to stargazing. The best way to learn the constellations is to use the ones you can recognize to help you find the ones you're not familiar with and the ones that aren't as quite as bright. Another fun way to learn to navigate the sky is star hopping, traveling from one star to another across the celestial dome with your eyes rather than a space ship. It really works well!
Our starting point is going to be very easy to find, the Big Dipper, the rear end and tail of the constellation Ursa Major, the Big Bear. We won't worry about the rest of the Big Bear right now, we'll just concentrate on the Big Dipper, which is hanging upside down in the early evening April sky. The first thing we want to do is face north and look up at the two stars on the left side of the pot opposite the handle. Shoot a line downward from those two stars, Merak and Dubhe, and you'll run right into Polaris, otherwise known as the North Star. If you extend a clenched fist at arm's length, three of those fist widths will get you from Dubhe to Polaris. Polaris is the brightest star in the much fainter Little Dipper, and Polaris is positioned at the end of the handle.
Next, face due east as best you can. From that vantage point the Big Dipper will appear to be standing on its handle. Extend the arced line of the principle handle stars Alioth, Mizar, and Alkaid beyond the handle and you arch yourself directly to the very bright and orange-hued star Arcturus. This famous star hopping tip is called "arc to Arcturus."
Arcturus is one of the brightest stars in the spring, and serves as the brightest star in the constellation Bootes the Herdsman or Farmer. Facing to the east, Bootes actually looks much more like a big sideways kite pointing to the left or north, with Arcturus serving as the tail of the kite. Some folks see Bootes as a one scoop ice cream cone lying on its side.
Astronomically, Arcturus is considered a bloated red giant star nearing the end of its life. It's over 21 million miles in diameter, which is about 25 times the diameter of the sun. It used to be about the same size as our sun, but crazy helium fusion has caused it to rapidly expand. Arcturus lies about 37 light- years from Earth, with just one light- year equaling nearly 6 trillion miles! The light we see from Arcturus tonight originally left that great star when Jimmy Carter was still our president in 1980.
Arc to Arcturus isn't the end of the arc though. Continue the arc and you'll eventually run into a bright star with a slighty blue hue. That's Spica, in the low southeast heavens. I've also heard the adage "arc to Arcturus and then spike to Spica." Actually, it's more like an arc to Spica rather than a spike.
Spica, about 250 light years away and nearly eight times the diameter of our sun, is the brightest star in the very large but very faint constellation Virgo the Virgin. Spica is close by one of my favorite constellations, Corvus the Crow. If you're still facing east look for a lopsided trapezoid to the right or south of Spica. That trapezoid is supposed to be a crow? Good luck seeing that!
For extra credit look for an extremely bright star very close to the horizon, a little below and to the left of Spica. That's no star, that's the largest planet in our solar system, Jupiter! At 88,000 miles in diameter, about 1,200 Earths could fit inside of Jupiter, if it was hollow of course!
There you have it, a classic example of star hopping in the sky. With any star map you discover other star hopping tricks to travel all around the great celestial dome, making the stars your old friends!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is also the author of "Stars: a Month by Month Tour of the Constellations," published by Adventure Publications and available at bookstores and at adventurepublications.net. Contact Mike Lynch at mikewlynch@comcast.net.