Discover celestial treasures overhead
This week in Starwatch I want to go sky high to reveal some of the great visual treasures waiting for your eyes.
And now that it gets darker a lot sooner in the evening it’s easier to get out there and stargaze before the sandman starts working on your eyelids. You can spend a lot more time with your telescope.
There are a lot of celestial treasures among the constellations in the late summer sky. Star clusters, nebulae, double stars and even whole other galaxies outside our Milky Way are hidden from the naked eye, but with a little patience and optical aid you can dig them out.
Three of the nicest jewels of the Butler heavens right now are nearly overhead at the end of evening twilight, around 9 p.m. The easiest one to see is the star Albireo, the second brightest star in the constellation Cygnus the Swan, otherwise known as the Northern Cross.
The best way to find it is to face south and look directly overhead. The brightest star you see is Vega, the brightest star in the constellation Lyra the Lyre (or Harp).
Make a fist and extend your clenched fist at arm’s length. About two fists at arm’s length to the left of Vega look for the Northern Cross. The moderately bright star at the foot of the cross is Albireo.
To the naked eye, Albireo looks like any other star in the sky, but with even a pair of binoculars, you can see that not only is Albireo a double star, but a colorful pair. One star has a golden hue and the other is distinctly blue. I guarantee you’ll love what you see.
The double stars of Albireo are considered a binary star system, almost 400 light years away, with just 1 light-year equaling nearly 6 trillion miles. The latest information indicates that the two gravitationally bound stars are separated by more than 400 billion miles and orbit each other once every hundred thousand years.
The next celestial treasure to search for is more elusive and you’ll need at least a small to moderate telescope. It’s the Ring Nebula. More formally known as Messier object 57, or M57.
It really looks like a ring and with its slightly bluish tint it reminds me of a little cosmic smoke ring. The Ring Nebula is in the constellation Lyra the Harp, between two of the four stars that make a little parallelogram allegedly outlining the little celestial harp.
Just keep scanning between the two stars that make up the end of the parallelogram opposite the bright star Vega. At first the Ring Nebula looks like a faint blurry star, but if your scope is powerful enough you may be able to resolve the ring.
M57 is what astronomers call a planetary nebula, a dying star shedding off the last of its hydrogen gas as it collapses into a white dwarf star, about the size of our Earth. Our own sun is headed for this fate in about 5 billion to 6 billion years.
The final celestial treasure I have for you is the most challenging. It’s the Dumbbell Nebula, more formally known as Messier Object 27, or M27. It’s also a planetary nebula that actually looks like a giant dumbbell weight.
With a really good pair of binoculars or a small telescope with a low magnification, scan about half a fist width at arm’s length to the lower left of Albireo, looking for a ghostly patch of white. If you’re out of heavy city lighting and your optics are good enough you should see the dumbbell shape.
While you’re out under those great countryside skies you can’t help but see the ribbon of white that stretches across the top of the sky from the northern to southern horizons.
It’s the Milky Way band. Our sun and all the stars in the celestial dome are members of our home Milky Way galaxy. The ghostly band we see is the combined light of billions and billions of stars that make the thickest part of galactic home.
Celestial hugging
During the early morning twilight about an hour before sunrise the planets Venus, Mars and Mercury are in a fairly tight cluster in the low eastern.
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 available at bookstores at www.adventurepublications.net
