In a Big Year for Telescopes, Much Peering Into Wallets

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Golden Year for Astronomy

After its invention more than 400 years ago, telescopes are still recognized as the greatest marvels of civilization. This year, the U.S. plans to launch new telescopes and maintain older ones in hopes of discovering a larger Multiverse.

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Galileo "wouldn't have had the cultural reference frame to appreciate or understand all this stuff," opines Andrea Prestwich, an astronomer with the Harvard-Smithsonian Center for Astrophysics. "First of all, he'd get stuck on the scale of the universe."

While cosmologists hash out the biggest questions, astronomers are taking on something slightly simpler and closer to home: How big is our Milky Way galaxy?

Astronomer Mark J. Reid, also with the Center for Astrophysics, tried to answer that question by using 10 telescopes spread across the continental United States, Hawaii and the Caribbean. The Very Long Baseline Array, as it is known, functions in certain respects like a single instrument with nearly the diameter of Earth.

Recently, the operators of the VLBA learned how to take into account such subtle, data-skewing effects as continental drift. The array is now so powerful, Reid said, that it would be able to read his PowerPoint slides from the moon.

By studying individual stars and calculating their speed and distance, Reid discovered that the Milky Way galaxy is rotating faster than scientists had thought and is half again more massive. That means it is not the little sister of the nearby, supposedly larger Andromeda Galaxy, but more like a fraternal twin. It's also more likely to collide with Andromeda in a few billion years.

"It's not going to be a hard collision," Reid said. "The galaxies are mostly empty. The distances between stars is big. We're not going to feel it."

But the gravitational chaos of two galaxies colliding could conceivably hurl Earth into the intergalactic void.

"Then we could look back and see what the Milky Way looks like," he said, putting a happy spin on the prospect of being exiled into intergalactic nothingness.

A Small Place for Life

Despite all that's been discovered, the universe remains deeply enigmatic. Astronomers want to get a handle on the unseen dark matter, the existence of which is inferred from the motion of galaxies. They'd like to understand that dark-energy stuff -- what is it, exactly? They'd like to know how galaxies formed, and why they tend to have black holes at their centers.

And, of course, the astronomers are hungry to find new planets. They have found more than 300 in the past decade -- new worlds orbiting distant stars. Almost all are gas giants, very hot, even larger than Jupiter. The next great leap will be the discovery of small, rocky, Earth-like planets.

Eventually, said John Mather, a Nobel-laureate NASA scientist who has worked on the Webb telescope, "we will find planets, around other stars, that are alive."

A constant in the history of the telescope is that new instruments inevitably change our view of the cosmos. Another constant is that the Copernican model, in all its significance, continues to hold. There does not appear to be anything particularly special about our place in the universe.

"Life is sort of a small fraction of what the universe is about -- depending on your perspective," said Adam Burrows, a Princeton astronomer. "If you look out in the universe, it's a pretty dead place. . . . Anyone coming from [Galileo's] time would be shocked by the diminution of mankind in the context of the universe."

But, he added, "Galileo would be less shocked than most."