Washington, D.C. Two independent groups have simultaneously made the first-ever ground-based detection of extrasolar planets thermal emissions. Until now, virtually everything known about atmospheres of planets orbiting other stars in the Milky Way has come from space-based observations.

Three undergraduate students, from Leiden University in the Netherlands, have discovered an extrasolar planet. The extraordinary find, which turned up during their research project, is about five times as massive as Jupiter. This is also the first planet discovered orbiting a fast-rotating hot star.

An international team of astronomers has discovered the largest-radius and lowest-density exoplanet of all those whose mass and radius are known. It is a gas-giant planet about twice the size of Jupiter, and is likely to have a curved cometlike tail. It has been named TrES-4, to indicate that it is the fourth planet detected by the Trans-atlantic Exoplanet Survey (TrES) network of telescopes.

Astronomers say they have found the first conclusive evidence of water outside our own solar system. The scientists say they have found evidence of water vapor in the atmosphere of a giant planet, called HD 18933b, more than 60 light-years away.

Astronomers who used powerful telescopes in Arizona and Chile in a survey for planets around nearby stars have discovered that extrasolar planets more massive than Jupiter are extremely rare in other outer solar systems.

Observing the image of a faint object that lies close to a star is a demanding task as the object is generally hidden in the glare of the star. Characterising this object, by taking spectra, is an even harder challenge. Still, thanks to ingenious scientists and a new ESO imaging spectrograph, this is now feasible, paving the way to an eldorado of many new thrilling discoveries.

The world is abuzz with the discovery of an extrasolar, Earth-like planet around the star Gliese 581 that is relatively close to our Earth at 20 light years away in the constellation Libra.

When we think of extrasolar Earth-like planets, the first tendency is to imagine weird creatures like Jar Jar Binks, Chewbacca, and, if those are not bizarre enough, maybe even the pointy-eared Vulcan, Spock, of Star Trek fame.

"HD 149026b is simply the most exotic, bizarre planet," Harrington said. "It's pretty small, really dense, and now we find that it's extremely hot."

Astronomers have found the most Earth-like planet outside our Solar System to date, a world which could have water running on its surface. Scientists say the benign temperatures on the planet mean any water there could exist in liquid form, and this raises the chances it could also harbour life.

ESA's Darwin mission will look for extrasolar planets and signs of life. The Agency's Technology Research Programme has sponsored the development of critical optical components whose frictionless mechanism can respond to the touch of a feather.