When my mother and father were school kids, there weren’t any galaxies besides our own Milky Way. Today, we know there are billions of them in a universe that spans billions of light years. Where did they all come from? Did they spring suddenly into existence? Of course not. They have been there for billions of years, but it wasn’t until Edwin Hubble’s astonishing announcement in 1925 that anyone knew the universe was more than the Milky Way.
Many stars aren’t stars at all
I can still clearly remember my mother’s befuddlement when I told her that many of the “stars” she sees in the night sky aren’t stars at all, but distant galaxies of millions or billions of stars. Because she had gone to school before Hubble’s discovery, she struggled to comprehend the concept that enormous galaxies are so incomprehensibly distant from us that they appear to be only tiny dots of light and seem to be just other stars.
This is no criticism of my mom. After all, having endured the Great Depression, World War II and raising four kids, her attention and concerns were understandably earth-bound. And I’m grateful to her that they were. Galaxies that are billions of light years from our little Albany home had absolutely no effect on her pinching pennies to clothe her family and put meals on our table. Nor do they affect those things today.
Nevertheless, while stars, planets and galaxies have no relevance on our mortgage payments or car maintenance bills, their wonder and mystery retain a fascination that has endured since our predecessors first walked upright. And today, we know so much more about them and the rest of the cosmos. No longer do we imagine the world as a flat plate borne on the back of a tortoise or on an elephant. The Milky Way is no longer viewed as a river of milk spilt by Hera as she nursed Heracles. Stars are not holes in black fabric and formations on Mars are not canals.
But humans, being the extremely curious creatures that we are, can’t help but to ask questions — to wonder to explore, to solve mysteries, to understand the inexplicable, to seek answers to those big questions. And so, 400 years ago in 1609 (the same year Henrik Hudson first explored the river that bears his name), Galileo turned his telescope heavenward and discovered the first four moons of Jupiter, mountains and craters on the moon and sunspots (which can affect daily life). Perhaps his most significant observation was of the phases of Venus which led him to support Copernicus’s treatise that the sun, not the earth, is the center of the solar system. This view ultimately sent him to trial by the Inquisition which sentenced him to house arrest for the rest of his life.
Our curiosity grows
As is so often the case, the more we learn, the more questions we uncover and the more curious we become. Galileo observes spots on the sun. Immediately we want to know “What are they?” “What causes them?” “Can they affect us?” Edwin Hubble observes that the more distant galaxies are racing away faster than nearby galaxies and that universe is expanding. Immediately, scientists wonder, “Will it ever stop expanding?” “Why is it expanding?” “When did it start expanding?”
These ever-curious humans build bigger telescopes; they build radio telescopes; they send the Hubble telescope into orbit; they send probes to nearby planets; they send orbiters and landers chock full of instruments to Venus, Mars, Jupiter, Saturn. They send men to walk on the moon and carry home rocks for analysis. They send Spirit and Opportunity to roam around Mars for three months and the valiant little explorers photograph and dig and analyze for five years and counting.
And the curious humans learn more, and the more they learn the more they want to know. So they launch telescopes to observe the universe beyond the visible spectrum: Chandra to view the cosmos by X-rays, Spitzer to look at the infrared and FUSE the ultraviolet. But our home world is not neglected. Dozens of satellites orbit our planet constantly, monitoring weather, climate, carbon, water, atmosphere, radiation and conveying communications, and GPS to help us to not get lost.
Get out there and see what’s out there
We all can play, and winter is a great time to join in the fun. Because cold winter air is often exceptionally clear, the heavens can sparkle with rare clarity. Here are some of the “naked eye” astronomical highlights in February 2010.
1. The planet Mars is in opposition and will shine beautifully through February 19 as one of the brightest objects in the night sky. Imagine the rovers, Spirit and Opportunity, busily at work up there!
2. The Orion Nebula is the closest birthplace of stars to Earth. Find the middle “star” in sword hanging from the belt of the Orion constellation.
3. From February 4-6 and 21-23, the Sun will be at an angle to the Moon to best reveal terrain. The new moon is February 14, which is the best time to view stars and planets.
4. To find out when you can spot the International Space Station passing over, go to www.jsc.nasa.gov/sightings/ (not only in February, but any time).
Ed. Lange writes “Guy Stuff” monthly for Capital Region Living. He may be reached at firstname.lastname@example.org.