During a talk today, Nasa announced that humanity will encounterextra-terrestrials within a decade. 'I believe we are going to have strongindications of life beyond Earth in the next decade and definitive evidence inthe next 10 to 20 years,' said Ellen Stofan, chief scientist for Nasa,(pictured) at a Washington panel discussion
'We know where to look, we know how to look, and in most cases we have thetechnology.'
Jeffery Newmark, interim director of heliophysics at the agency, added:'It's definitely not an if, it's a when.'
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'We are not talking about little green men,' Stofan said.'We are talking about little microbes.'
The announcement has been prompted by the recent discovery of water byNasa in surprising places.
Jim Green, director of planetary science at Nasa, noted that a recentstudy of the Martian atmosphere found 50 per cent ofthe planet's northern hemisphere once had oceans a mile deep.
NASA's Head Scientist says don't expectlittle green men!
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Scientists using the Hubble recently provided powerful evidence thatJupiter's moon Ganymede (pictured) has a saltwater, sub-surface ocean, likelysandwiched between two layers of ice
The same study found that water had been present on the red planet for upto 1.2 billion year.
'We think that long period of time is necessary for life to get morecomplex,' Stofan said.
Nasa associate administrator John Grunsfeld said he is excited aboutseeing what form life beyond Earth may take.
BILLIONS OFEXOPLANETS ARE MORE EARTH-LIKE THAN THOUGHT
Intheir hunt for alien life, astronomers have so far focused on looking forEarth-like planets around smaller, cooler suns.
Butthese exoplanets - despite having a chance of holding water - are believed tobe locked in a rotation around their sun which causes only one side of theirsurface face the star.
Nowastronomers claim that such exoplanets actually rotate around their stars, andspin at such a speed that they exhibit a day-night cycle similar to Earth –increasing the chance of finding alien life.
Planetswith potential oceans could have a climate that is much more similar to Earth'sthan previously expected,' said Jérémy Leconte, a postdoctoral fellow at theCanadian Institute for Theoretical Astrophysics (CITA) at the University ofToronto.
'Ifwe are correct, there is no permanent, cold night side on exoplanets causingwater to remain trapped in a gigantic ice sheet,' he said.
'Whetherthis new understanding of exoplanets' climate increases the ability of these planets todevelop life remains an open question.'
'Once we get beyond Mars, which formed from the same stuff as Earth, thelikelihood that life is similar to what we find on this planet is very low,' hesaid.
'I think we're one generation away in our solar system, whether it's on anicy moon or on Mars, and one generation [away] on a planet around a nearbystar.
Scientists using the Hubble recently provided powerful evidence thatJupiter's moon Ganymede has a saltwater, sub-surface ocean, likely sandwichedbetween two layers of ice.
Jupiter's moon Europa and Saturn's satellite Enceladus are also thought tohave an ocean of liquid water beneath their surface in contact with mineral-rich rock.
This, according to Nasa, means they may have the three ingredients neededfor life as we know it.
'The science community is making enormous progress,' said Green.
'And I've told my team I'm planning to be the director of planetaryscience when we discover life in the solar system.
At the same conference last year, Nasa Administrator Charles Bolden made amore conservative estimate.
He claimed that we will find life within the next 20 years - with a highchance it will be outside our solar system.
Nasa next Mars rover, scheduled to launch in 2020, will search for signsof past life and bring samples for a possible return to Earth for analysis.
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New Horizons took this image of the icy moon Europa rising above Jupiter'scloud tops. The space agency is planning a mission to Europa, which maylaunch as early as 2022, to find out whether the moon is habitable
Aliens: What are the odds of actuallyfinding them?
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Nasa also hopes to land astronauts on Mars in the 2030s, which Stofan saysis crucial key to the search for Mars life.
'I'm a field geologist; I go out and break open rocks and look forfossils,' Stofan said. 'Those are hard to find.
'So I have a bias that it's eventually going to take humans on the surfaceof Mars — field geologists, astrobiologists, chemists — actually out there lookingfor that good evidence of life that we can bring back to Earth for all thescientists to argue about.'
The space agency is also planning a mission to Europa, which may launch asearly as 2022. It hopes to find out whether the icy moon is habitable.
Meanwhile, the agency's James Webb Space Telescope (JWST), will launch in2018 to scope out the atmospheres of nearby 'super-Earth' alien planets.
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