Facts of the Matter
Two weeks ago in the western sky, the lingering glow of dusk gave way to an unusual heavenly display as five of the nine planets lined up in a show that had people looking at the sky in record numbers.
Brighter than anything except the sun and moon, the visible planets have fascinated mankind from earliest times. Planets are 'wanderers,' roaming around against the fixed background of stars, and have aroused curiosity, wonder and mythology around the world.
The ancient and occult art of astrology arose from mythology thousands of years ago as people tried to predict human affairs from the mysterious movements of the planet.
Events such as the recent planetary alignment happen every three or four decades and have been looked upon as portending some significant earthly catastrophe, or the end of the world, in virtually every case since the beginning of time.
None of the dire predictions have come true, and there is no known scientific basis for the claims. The fact that such fears linger is a testament to the deep-rooted relationship that we have with the sky and its starry inhabitants.
More common but equally striking celestial light shows are planetary conjunctions, when two planets appear extremely close to one another in the sky. The most famous conjunction occurred on the night of June 17, 2 B.C., when Venus and Jupiter were so close that they appeared to be an extremely bright single object. These are the two brightest planets, and astronomers have speculated that this could have been the "Star of Bethlehem" described in the New Testament.
A conjunction of these same two planets will be clearly visible in the sky tonight and tomorrow just above where the sun sets, from 7:30 to 9 p.m. Although not as spectacular as the conjunction 2,000 years ago, it is worth a look.
Since Venus moves against the star background rapidly, its motion is easily noticeable from one night to the next, especially when it is close to another planet. If you watch for a few nights, you will see the two planets separate as Venus is lost in the glow of the setting sun.
Although it appears that the planets are close together, this is just an illusion. In reality, Venus and Jupiter will be nearly 450 million miles apart at conjunction, so they can't collide now, or ever, no matter how close they appear to pass. The vastness of interplanetary space destroys any three-dimensional effects.
We are not great observers of the sky compared with our ancestors. Bright city lights and air pollution have reduced the visibility so much that most of us don't know what the sky really looks like, and we spend most of our time indoors. Our ancient ancestors were diligent and skilled observers but lacked our modern knowledge of the structure of our solar system, the Milky Way galaxy and the infinite universe of which we are a part.
To many of us the sky is just "there," but now and then the heavens put on a show that has a serene beauty as well as a calming sense of order. Take a look at this planetary dance when you get a chance. These balmy spring evenings are as good a time as any to experience the wonder and beauty of the nighttime sky that has stirred the hearts of mankind for millennia.
We could all be a little smarter, no? Richard Brill picks up
where your high school science teacher left off. He is a professor of science
at Honolulu Community College, where he teaches earth and physical
science and investigates life and the universe.
He can be contacted by e-mail at firstname.lastname@example.org