Astronomers discover first potentially life-sustaining planet

A team of planet hunting scientists on Wednesday announced the discovery of a planet with three times the mass of Earth orbiting in the habitable zone of a nearby star.

The research was funded by the National Aeronautics and Space Administration (NASA) and conducted by investigators from the University of California (UC) Santa Cruz and the Carnegie Institution of Washington.

The discovery was a result of eleven years of observations of the red dwarf star Gliese 581 using the W.M. Keck Observatory in Hawaii, one of the world's largest optical telescopes. The planet is located in an area where liquid water could exist on its surface.

"Our findings offer a very compelling case for a potentially habitable planet. The fact that we were able to detect this planet so quickly and so nearby tells us that planets like this must be really common," said Steven Vogt, co-leader of the investigation.

The discovery, if confirmed, would be the most Earth-like exoplanet found so far, and the first strong case for a potentially habitable planet. According to astronomers, a potentially habitable planet is the one that could sustain life, not necessarily human life. Investigators used the HIRES spectrometer on the Keck I Telescope for precise measurements of a star's radial velocity which is its motion along the line of sight from Earth. By analyzing the star's radial velocity, astronomers are able to reveal the presence of planets.

The gravitational tug of an orbiting planet causes periodic changes in the radial velocity of the host star. Multiple planets induce complex wobbles in the star's motion, and astronomers use sophisticated analyses to detect planets and determine their orbits and masses.

"Keck's long-term observations of the wobble of nearby stars enabled the detection of this multi-planetary system. Keck is once again proving itself an amazing tool for scientific research," said Mario R. Perez, Keck program scientist.

The new planet designated Gliese 581g has a mass three to four times that of Earth and orbits its star in just under 37 days. It is believed to be a rocky planet with enough gravity to hold on to an atmosphere.

Gliese 581g lies right in the middle of the habitable zone, the specific distance from the sun that allows a life-sustaining habitat to evolve. The planet is tidally locked to the star, which means that one side is always facing the star and basking in perpetual daylight, while the side facing away from the star is in perpetual darkness. The habitable zone would probably be line between light and darkness.

Source: Bnonews.com