Our Milky Way Galaxy provides plenty of cool sights
There’s still a lot of great stargazing you can do even if you live in an urban-suburban setting, but unfortunately the street lights, strip malls and more have cast a permanent luminance across our formerly dark night skies.
One of the celestial victims is the Milky Way, that magical ribbon of light that runs through the summer skies. It has vanished.
Head out to the countryside, though, and you can recapture its magnificence. It’s well worth at least one trip in the late summer or early fall.
Once you’re out there under the starry canopy, the great white river will be waiting for you. It arches across the high eastern sky, meeting the horizon in the northeast and southwest.
By 10 p.m. the arch rises high enough to bisect the sky. You’re witnessing the billions of stars that make up the thickest part of the disk of stars we call our home galaxy, the Milky Way.
The diameter of the Milky Way spans an incredible 100,000 light years, with just one light-year equivalent to nearly six trillion miles. There are so many stars in our line of sight in the Milky Way band that it appears as a milky ribbon in the sky. That’s how the galaxy got its name, long before us Earthlings knew what we were really looking at.
Along the starry river of the Milky Way are some prominent constellations. On the northeast side is Cassiopeia the Queen, the one that looks like a sideways letter W. According to Greek mythology, the W depicts Cassiopeia, the queen of mythological Ethiopia.
The very vain queen got in trouble with Hera, the queen of the gods of Mount Olympus. Cassiopeia claimed she was beautiful, in fact even more beautiful than Hera. This made Hera so angry that she swooped down from Olympus, tied Cassiopeia up in her throne and pitched her up in the sky so she could show the entire world how beautiful she is. Cassiopeia’s been marooned up there ever since.
About halfway across the Milky Way, high in the eastern sky, look for three bright stars, the brightest ones in that area. They form what’s known as the Summer Triangle. While it’s not an official constellation, it’s a great tool. The triangle will help you find three constellations, since those three stars are the brightest in their respective constellations: Lyra the Harp, Aquila the Eagle, and Cygnus the Swan.
Cygnus is nicknamed the Northern Cross since that’s what it actually looks like. It’s brightest star is Deneb, which doubles as the top of the cross and tail of the swan. Cygnus as the Northern Cross lies horizontally in the river of the Milky Way. Cygnus as a swan appears to be flying through the stream of stars.
On the southwest end of the Milky Way, near the horizon, is the zodiac constellation Sagittarius, the archer, that looks a heck of a lot more like a teapot than a half-man, half-horse creature shooting an arrow at a scorpion. This is the most significant section of the Milky Way river since it’s towards the center of our galaxy.
That part of the Milky Way band would be a whole lot brighter, except there’s a lot of opaque interstellar gas and dust. If it weren’t for that, it’s believed that this part of the Milky Way would be as bright as a full moon. Astronomers know what’s behind those clouds because they’ve looked into the Milky Way with infrared and X-ray telescopes that can see past the clouds to get a better idea of what’s going on.
At the heart of the Milky Way lies a massive black hole that may be more than 14 million miles in diameter. Our own sun is less than a million miles in diameter. It’s also believed to be around four million times the mass of our sun. It’s thought by many astronomers that the gargantuan central black hole is the collective remains of gigantic stars that died a long time ago. There’s a lot going on behind those clouds!
You probably don’t have an X-ray or infrared telescope or space probe, but with just a small telescope or decent pair of binoculars you can have a lot of fun.
You’ll also discover quite a few celestial treasures like bright nebulae clouds where stars are being born, dark rifts of hydrogen gas, and clusters of young stars. You might even see a few manmade satellites rolling across the heavens.
Lie back on the ground and roll your eyes across the sky and especially around the Milky Way band.
This week is actually a pretty good time to plan such an adventure because the moon doesn’t rise until well after midnight.
I guarantee that this will be a treat that you’ll remember for a long time, no matter if you’re by yourself or with family or friends.
Celestial hugging
The waning crescent moon will be hanging out with the planets Venus and Mars this week in the pretwilight eastern sky.
On Thursday morning the moon will be just to the lower left of Venus and a little to the right of Mars. With a small telescope or even a pair of binoculars you’ll see that Venus is crescent shaped just like the moon.
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul and is author of the book, “Stars, a Month by Month Tour of the Constellations” published by Adventure Publications and available at bookstores and at www.adventurepublications.net.
