Are You There, Life In Space?

Former astronaut John Grunsfeld has concluded that aliens may spot humans from afar due to the changes we've made to the earth's environment., according to dailymail.

"We put atmospheric signatures that guarantee someone with a large telescope 20 light years away could detect us," said Grunsfeld at the Astrobiology Science Conference in Chicago. "If there is life out there, intelligent life, they'll know we're here."

The associate administrator for Nasa's Science Mission Directorate, added: "'Are we alone?' is the biggest driving question.'"

Earlier this year, Nasa's chief scientist Ellen Stofan could even find evidence of extraterrestrial life in the next 20 to 30 years. "We know where to look, we know how to look, and in most cases we have the technology," he said.

Jeffery Newmark, interim director of heliophysics at the agency, added: "It's definitely not an if, it's a when."

"We are not talking about little green men," Stofan said. "We are talking about little microbes."

Recently, water was discovered by Nasa in some strange places. Jim Green, director of planetary science at Nasa, found in a recent study of the Martian atmosphere, that there were 50 per cent of the planet's northern hemisphere, which once had mile-deep oceans. Moreover, the Red Planet had water for 1.2 billion years.

"We think that long period of time is necessary for life to get more complex," said Stofan.

Astronomers at the time examined smaller, cooler suns, which they called exoplanets, in spite of their possibility of holding water. They tend to be locked in a rotation around their sun, which caused just one side of their surface to face the star.

Now astronomers claim that such exoplanets do rotate around their stars at a speed similar to the earth's day-night cycle.

"Planets with potential oceans could have a climate that is much more similar to Earth's than previously expected," said Jérémy Leconte, a postdoctoral fellow at the Canadian Institute for Theoretical Astrophysics (CITA) at the University of Toronto. "If we are correct, there is no permanent, cold night side on exoplanets causing water to remain trapped in a gigantic ice sheet," he said. "Whether this new understanding of exoplanets' climate increases the ability of these planets to develop life remains an open question."

"Once we get beyond Mars, which is formed from the same stuff as Earth, the likelihood that life is similar to what we find on this planet is very low," he added. "I think we're one generation away in our solar system, whether it's on an icy moon or on Mars, and one generation [away] on a planet around a nearby star."

Nasa Administrator Charles Bolden claimed that life can be found in the next 20 years---but it will not be in the solar system.