FARMINGTON – Is the earth in danger from asteroids? Could reality match the action of “Armageddon,” the Bruce Willis blockbuster tale about an asteroid hurtling toward Earth?

Local associate professor of physics Christopher Magri doesn’t think we ought to put too much stock in that stereotypical solution, explaining Wednesday why rockets and bombs would probably not be capable of stopping an asteroid from hitting Earth.

Magri, a Cornell graduate who teaches at the University of Maine at Farmington, is one of about a half-dozen astronomers in the world who do radar studies of asteroids and is among those whose asteroid work is featured in the Nov. 24 issue of Science Magazine. (Go to www.sciencemag.org for details of the group’s findings.)

As part of a group headed by astronomer Steve Ostro, of the National Aeronautics and Space Administration’s Jet Propulsion Lab, Magri participated in an in-depth radar study of asteroid 1999 KW4, trying to understand what makes objects like it tick.

Magri’s role in the study – working with the complex computer programs used to read the data – was much more creative than it might sound. Once, he said, the program read the data in such a way that it depicted KW4 with long spikes coming out all over – much like a sea urchin. While that’s not impossible, it is highly, highly unlikely, Magri said. So he went in and worked with the code in the program to come up with a more realistic version of the asteroid

KW4, as the asteroid now known, was discovered in 1999 and classified as potentially hazardous because future changes in its orbit could eventually bring it it into contact with Earth – but not for at least 1,000 years, Magri said.

Because even if KW4 never approaches hitting Earth, another asteroid like it probably will.

With funding from NASA and the National Science Foundation, the group learned about KW4’s orbit when it passed especially close to the Earth in 2001.

They also found out some potentially terrifying facts. Because they’re binary – or two-part – asteroids, KW4 and other similar asteroids would be extremely hard to stop, if they were on a collision course with Earth.

That’s a big deal.

Congress asked astronomers to search out at least 90 percent of all potentially hazardous asteroids big enough to do serious damage to the Earth, Magri said, because it’s virtually certain that one will hit, eventually.

“We know that big things have hit the Earth, and we know the day is going to come when it gets hit again,” Magri said. “If they hit the Earth, you get global devastation. It’s a bad day for everyone.”

Traditionally, scientists have discussed three possibilities for altering the course of an asteroid that will hit the Earth, Magri said. “What do you do – Bruce Willis style,” he asked. “You blow it up.” That’s method number one, he said.

“That would be really hard to do on an object like KW4.” Made up of two porous amalgamations of rock that orbit each other, both with extremely weak gravitational fields, it would not only be nearly impossible to land a spacecraft on a KW4-like asteroid – it would also be hard to get anything to stay on. “Stuff there is just barely attached,” he said. It might be possible anyway, he said. A little movement over a period of 20 years or so could do the trick.

The third idea, according to Magri, involves having a spacecraft hover close to an asteroid for a long time, exerting a slight gravitational tug that gradually pulls the asteroid onto a changed course that misses Earth. Since the gravitational force between spacecraft and asteroid has nothing to do with whether or not the asteroid is porous, this method could work for an object like KW4.

Its a good thing scientists are learning about these problems now, Magri said, because finding a solution takes decades, if not more.

“By learning more about this object which we can study well, it helps us understand what such objects are like, so we can do something about it when we find one that is going to hit us,” he said.

On another hot topic, nearly all astrophysicists believe there is life on other planets or moons, Magri said. What they disagree on, he said, is whether there is intelligent life. Magri himself thinks there probably is. But nearly all astronomers – Magri included – believe aliens have not, indeed, landed on the Earth at this point. There is no real evidence for that, he said.