Double Treat for Early Risers
Observing >
There is an aesthetically pleasing phenomenon occurring this week, one that happens often, but is always beautiful to look at nonetheless. And this one is promised to the people who awaken early, those who sometimes miss the late night starry happenings because of their schedule.
In the east, for the hour before sunrise on the mornings of both Thursday the 4th and Friday the 5th, you will see two bright star-like lights, nearly touching. These two are the planets Venus and Jupiter.
Venus is the brighter one, not certainly because it is bigger --- it is smaller by plenty --- but because it is so much closer. And its permanent cloud shroud allows it to reflect a lot of light. Jupiter, although it appears to be dancing a little too close to the seductive Venus, is actually over 460 million miles farther away in this celestial optical illusion.
It is these two planets that played a major role in overturning the ancient view of the heavens over 400 years ago. And they changed it just by being seen!
It was believed for thousands of years that the earth was the center of the universe. It is easy to see why this belief was held. For one thing, everything appears to be going around us: the sun, the stars, and those crazy "wandering stars" with minds all their own, which we now call planets. And of course the earth doesn't feel like it's moving. It feels like we're just sitting here, doesn't it?
But no matter how hard early mathematicians and astronomers tried to force a model of the universe with the earth at center, it never quite worked perfectly. The planets and sun and moon seemed to want to do things differently. But why didn't they obey?
Could
it be that their nonconformist ways were due to the fact that they were
not going around the earth, but around the sun?! Some, most famously
a Polish monk named Copernicus, believed so.
During the 1500's some radical new thinkers tried to prove a model that had the sun as center. This proved very difficult. A lack of high-tech equipment assured that neither the sun nor earth could be absolutely established as the center, and the Copernican view just kind of sat there for a while, waiting for help.
Then the telescope was invented and a scientist named Galileo got a hold of one and pointed it to the skies.
The famously intelligent and infamously arrogant Galileo, a committed believer in the Copernican idea, made a new and improved telescope which had the amazing magnifying power of almost 9 times! But though the instrument was primitive by our standards, it was a colossal step forward for science four centuries ago. Why?
With it Galileo could look at our two planets, those same two rising together in the east this week, and see things there that literally no human eye had ever seen before.
In the winter of 1609 he spotted what looked like tiny stars around Jupiter. Were they just stars, or something brand new? Careful observing showed that night after night these little critters would seem to move around Jupiter as if in orbit about it.
One problem. Everything was supposed to go round the earth only, and nothing else. Going around Jupiter was against the old laws! Hmmm ...
Just
a short time later Galileo focused his telescope on brilliant Venus.
No tiny stars circling about here, but something just as important.
Imagine a universe with the earth as center and Venus flying around us. Beyond Venus the sun is circling us, as well. If that is so, if the sun is always farther than Venus, then Venus will only reveal to us a mostly shadowed version of itself when near the sun. We could never see a fully or near fully lit Venus since it can't get to the other side of the sun.
You'll never guess what Galileo saw. Of course he observed Venus in all its glorious phases, just as one would if Venus were traveling about the sun!
Slam dunk for the Copernican view? Not quite. There were still some details to be worked out, and old established ways are very difficult to give up, but Galileo had slammed two big nails into the earth-centered coffin: one nail named Jupiter, the other Venus.
And as the paradigm gradually shifted to the sun-centered view, modern astronomy was born.
As you look up to the double diamond later this week, think of what a profound impact these two points of light had --- just be being seen.
Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com.
Posted by Administrator at 2004.10.30 12:01 PM | Comments (0)
