SAN JOSE, Calif. (AP)--Two independent astronomy teams have confirmed for the first time the apparent existence of a planet orbiting a sun-like star outside the solar system.

Swiss astronomers Michel Mayor and Dider Queloz first announced on Oct. 6 that they had found a planet half the mass of Jupiter, orbiting a star named 51 Pegasus, about 40 light-years from Earth.

San Francisco State University astronomer Geoffrey Marcy said Tuesday that he has confirmed that the planet apparently exist.

The planet can't be seen because the nearby star's light drowns it out. After spending four nights using a powerful telescope at Lick Observatory in the mountains east of San Jose, Marcy detected a slight wobble in the star's movement. That would suggest a gravitational tug of a planet.

We've explored all sorts of alternative explanations and we've had the greatest minds in astronomy chiming in," he said. "The bottom line is nothing (else) explains what we see."

Astronomers previously had used similar evidence to show that at least two planets orbit a collapsed star known as a pulsar. Some scientists remain skeptical of the new discovery.

"I'd like to yell, 'Yes!' But I've seen these things fall by the wayside," George Gatewood of the University of Pittsburgh told the San Jose Mercury News. "The byways are littered with the corpses of (alleged) planetary systems."

Gatewood and others say the planet would be so close to 51 Pegasus, which is similar to our sun, it would be difficult for it to survive. And it wouldn't be the type of place to harbor life as we know it.

The Swiss astronomers said the planet's surface temperatures probably hover around 1,800 degrees because it's only about 5 million miles from its star. Earth is 93 million miles from the sun.

"I think it's still up in the air exactly what this beast is. Whatever it is, it's obviously an extremely exciting and interesting object," said David Black, director of Houston's Lunar and Planetary Institute.