Distances boggle the mind
Whenever I’m scanning the night skies with my telescope, I often have a hard enough time getting my mind wrapped around the distances to neighboring planets in our solar system, and when it comes to stellar and galactic distances, I often get brain overload!
The planet Saturn, for example, is around 800 million miles away, so far away that the light we see from it takes well over an hour just to reach our eyes.
By the way, do whatever you can to catch a view through a telescope of Saturn. It’s one of the best celestial jewels in the sky. I know I mention Saturn a lot in this column, but it’s something you just have to see, and right now you can see it early in the evening in the southern sky.
Just look for two fairly bright stars shining close together less than five degrees apart. That’s about the width of four of your fingers held together at arm’s length.
The star on the upper left is actually not a star but the wonderful planet Saturn.
The star on the lower right is Spica, the brightest star in the large but faint constellation Virgo the Virgin.
You better have a full tank if you’re headed to that star, as it’s more than 1,500 trillion miles away! Believe me though, that’s chump change compared to the distance of many other stars, even ones we can clearly see with our naked eye.
When it comes to stellar distance, you really need to express the distances in light-years or your head is bound to explode! One light-year equals just less than six trillion miles, which is the distance a beam of light travels in one year’s time.
Spica is about 263 light-years away, so the light we see tonight from the brightest star in Leo the Lion left that star in 1749, 77 years before the Declaration of Independence.
Mission impossible for me is trying to honestly comprehend the distance to other galaxies. All of the stars we see in our sky tonight are part of our Milky Way Galaxy, home to possibly more than a half a trillion stars including our home star, the sun.
This time of year in the southwestern evening skies not far from Spica and Virgo, it’s possible to see other galaxies with a telescope.
Just to the lower left of the distinct triangle that makes up the hind quarters and tail of Leo the Lion is the Virgo Cluster of Galaxies, part of the local group of galaxies that includes our own Milky Way galaxy.
Without a doubt you’ll need something a little beyond a starter telescope.
Even if that’s all you have, slowly scan that part of the sky with a low magnification eyepiece. See if you can spot fuzzy patches of light. There are well more than a dozen relatively bright galaxies, and if you manage to capture a glimpse of one or more of them I don’t think you’ll be doing back flips over the view.
Keep in mind: These less than impressive looking fuzz balls are other galaxies, some of which are much, much larger than our Milky Way and 60 million light-years away!
The galaxies that make up the Virgo cluster are truly, truly far away places!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and is author of the book, “Pennsylvania Starwatch,” available at bookstores and at www.lynchandthestars.com.
