Herb Palmer: Powerful telescopes seek new worlds in the skies
As we gaze at the moon on a chilly, clear night and the millions of flickering stars in the heavens, glittering from horizon to horizon, it appears to be just natural that we should wonder whether there are other planets like ours populated by pe...
As we gaze at the moon on a chilly, clear night and the millions of flickering stars in the heavens, glittering from horizon to horizon, it appears to be just natural that we should wonder whether there are other planets like ours populated by people just like us. A planet like Earth where life may have begun.
Do these planets have oceans and mountains, fish and fowl, farms and cities, just like we have here?
We are getting closer and closer to knowing, as a team of astronomers led by Geoffrey Marcy and Paul Butler has announced a new solar system more like our own than any other to date. It appears to be a system with two planets that orbit their sun -- the star 47 Ursae Majoris -- in almost circular orbits.
If you doubt that a system like ours with continents and oceans and maybe life could exist, there are teams of scientists determined to find the answers. Since 1991, more than 70 new planets have been identified circling other suns in the vastness of just our own solar system.
If you happen to think that we are alone in this great vastness, it's time to rethink your position. For example, from 1930, when Pluto was discovered, to 1991, we knew of no new worlds anywhere. Since then, the known roster of other planets in our galaxy has grown considerably, with 70 at last count. However, most of those found to date do not resemble the planets of our own solar system.
Lumbering around a star in our constellation Serpens, for example, is a planet 17 times the mass of our largest planet, Jupiter. Most of the newly discovered worlds tend to circle their suns in greatly elliptical orbits, rushing out to great distances, then closing in on them. If our solar system had planets like them, the Earth would have been destroyed long ago in a collision with one of them.
But the two worlds of 47 Urasae Majoris move in circular orbits much like Jupiter and Saturn, leaving plenty of room for other, smaller worlds that could have life. This is the type of peaceful system astronomers may have been looking for.
In the search for new worlds, scientists have found that through a telescope Pluto appears as a faint object 10,000 times dimmer than the faintest star visible to the unaided eye on a clear night. These new planets are billions of times fainter than Pluto. Even through the eye of the Hubble space telescope, orbiting 370 miles above Earth, they cannot be seen. The fact that theyhave been detected at all is the result of a strategy of searching and deduction that would make Sherlock Holmes proud.
In 1985, when they joined forces to begin the search, Marcy and Butler faced a daunting task on how to detect the presence of worlds too faint to be viewed directly. In the autumn of 1995, Marcy and Butler made their first discovery: a planet three times the mass of Jupiter orbiting the star of 47 Ursae Majoris. There were some beautiful and unexpected things about the orbit of this new planet. The star showed an apparent wobble, indicating that a planet was orbiting once every three Earth years in a nearly circular orbit.
Of all the Marcy-Butler discoveries, one made in 1999 was especially important. Originally, the searchers never expected to find even one planet around a star. To find a system of two planets would have been extraordinary. But the first system found around Upsilon and Andromedae had three. Imagine what lies ahead? With larger, more powerful instruments, we may be able to see into the future.
(Editor's Note: Material in this column was obtained from a news feature in Parade Magazine written by David H. Levy entitled "The Search for Other Worlds.")
On the lighter side . . .
I wish I had said that:
* Isn't it a bit unnerving that doctors call what they do "practice?"
* Where do forest rangers go to "get away from it all?"
* If a parsley farmer is sued, can they garnish his wages?
* Why do they lock gas station bathrooms? Are they afraid someone will clean them?
* Can vegetarians eat animal crackers?
* Why do they put Braille on the drive-through bank machines?
* What was the best thing before sliced bread?
A tall young man entered the bus with a very long pole. After much maneuvering, he sat down next to an elderly man.
"Are you a pole vaulter?" asked the man.
"Vell, no. I am not a Pole. I am a Norvegian. But how did yew know my name is Vaulter?'