ASTRONOMERS have discovered a planet that may be capable of supporting human life, and it's right at Earth's front door.

"It's not just in our backyard, it's right in our face," lead researcher Professor Steven Vogt said.



The planet is 22 light years away, previously thought to be 20 light years, and is formally known as Gliese 581g, but Professor Vogt told news.com.au that he has since named it after his wife.



"I called it 'Zarmina's world'," Professor Vogt said.



While his claims have been previously reported, a new study, released to News.com.au this week, dismisses calls of balderdash by the international science community.



The study - by astronomers at the University of California, Santa Cruz, and the Carnegie Institution of Washington - shows the "super Earth" is more than twice the size of Earth and is better able to hold on to its gassy atmosphere ,which increases its chances of retaining liquid.



"Having more mass makes for more gravity at the surface, making it more likely to be able to hold the atmosphere in place against evaporation from the planet," Prof Vogt said.



Whether this liquid is frozen and stored under the surface or flowing freely across the planet, the researchers can't say.



The scientist from the University of California said that the planet has "churchly weather".



"From the energy bounds, known brightness and temperature of the star, together with the known size of the planet's orbit and the estimated reflectance of the planet, we can compute the planet's temperature," Prof Vogt said.



"Surface temperatures over large regions of the tidally-locked planet would be just about right to be able to stand at the surface and feel the warmth of an alien Sun on your face, like standing in the park in Sydney."



However the researchers were unable to determine what the surface of the planet is like, Professor Vogt said.



The planet orbits in a region known as the Goldilocks Zone around the star. That region is where a planet's surface temperature is neither too hot, nor too cold for water to exist in liquid form- an essential ingredient for life as we know it.



Prof Vogt said Gliese was the most interesting planet for alien contact because of the relatively short delay times in interstellar communication.



"If you get lucky and find civilisations, you'd be able to have a two-way conversation within a human life-time," he said. "You don't want to have to spend 1000 years waiting to hear 'wazzup', and then another 1000 years before they get to hear not much, and you?'."



The researcher said after making first contact, scientists may receive an answer within 20 years.



"Using pulsed nuclear drive technology (basically dropping nuclear warheads out the back of your spacecraft and detonating them for propulsion), a ship carrying the equivalent of a super-sophisticated iPhone or Droid cell phone could reach this system in only a few hundred years and be able to send back picture postcards of its surface, sample its atmosphere for biomarkers, and listen for technological activity," he said.



"There is something out there."



These findings are not without controversy, however.



This isn't the first time Professor Vogt has claimed the existence of a habitable planet. His findings back in 2010 sparked a scientific cat fight between the US researchers and a rival team of Swiss astronomers. The team published research saying it had found four planets that orbited the same star as Gliese 581g (which at the time had not yet been confirmed).



Prof. Vogt's team added a large set of their own data to the Swiss team's data to confirm these four planets and uncovered two more planets in the system, including Gliese 581g, which orbitied in the star's habitable zone. Their work was published in the U.S.'s Astrophysical Journal.



The Swiss team almost immediately claimed that Vogt's research was nonsense, creating waves in the scientific community.



The international media then seized on both team's data, reporting problems with their research.



Prof Vogt said the international media took the Swiss team at its word.



"No one ever demanded that the Swiss produce data to back up their rebuttal," he said. "Even now, almost two years later, data to support their rebuttal has yet to appear in the peer-reviewed literature."



A year later the Swiss team released expanded data on its findings confirming the existence of four planets but not Vogt's extra two.



Vogts' team analysed the Swiss team's data set and found serious flaws with the Swiss analysis.



Prof. Vogt told news.com.au that they discovered that the Swiss had apparently omitted five key data points that simply did not fit their model of the system. These data points contained evidence for one or more planets in the system beyond the 4 confirmed ones. Vogt's team's analysis revealed that their model was highly unstable, with some planets colliding in as few as 15 years.



"You're basically deliberately deleting information in your data that's telling you there's more in the system than you're telling people about. You're hiding that stuff,” he told News.com.au.



Prof Vogt said the models were "completely unphysical" and could not be taken seriously. He also claimed the Swiss team set some of their orbits as circular while letting others remain "eccentric" or oval in shape, making their model unstable.



“Such setting of eccentricities introduces biases and personal choices into the model that inappropriately affect the resulting solution,” Prof Vogt wrote in the study, which was provided to News.com.au.



"One cannot in such modelling pick and choose which orbits to be eccentric or circular, " he told News.com.au.