September 19, 2013
NEW DELHI: Planet Earth will be able to support life for at least another 1.75 billion years – according to astrobiologists at the University of East Anglia. After that, the Sun's heat will become too much and water will no longer remain liquid on Earth.
September 19, 2013
NEW DELHI: Planet Earth will be able to support life for at least another 1.75 billion years – according to astrobiologists at the University of East Anglia. After that, the Sun's heat will become too much and water will no longer remain liquid on Earth.
Earth will remain habitable for at least another 1.75 billion years, a new study suggests.
"We used stellar evolution models to estimate the end of a planet's habitable lifetime by determining when it will no longer be in the habitable zone. We estimate that Earth will cease to be habitable somewhere between 1.75 and 3.25 billion years from now. After this point, Earth will be in the 'hot zone' of the sun, with temperatures so high that the seas would evaporate. We would see a catastrophic and terminal extinction event for all life. said Andrew Rushby, who led the research published in the scientific journal Astrobiology.
Actually, life as we know it will be over much before this deadline because of steadily increasing temperatures and consequent changes.
Does that mean that the great human civilization will perish? There is hope, the researchers point out. Our neighboring planet Mars, further away from the Sun, will become habitable as Earth becomes a cauldron. So Mars could be a place where humans can escape to. There is no atmosphere on Mars and any human colonization will have to build controlled climate units to live in.
"If we ever needed to move to another planet, Mars is probably our best bet. It's very close and will remain in the habitable zone until the end of the Sun's lifetime – six billion years from now," the scientists said.
Almost 1,000 planets outside our solar system have been identified by astronomers. The research team looked at some of these as examples, and studied the evolving nature of planetary habitability over astronomical and geological time.
"We compared Earth to eight planets which are currently in their habitable phase, including Mars. We found that planets orbiting smaller mass stars tend to have longer habitable zone lifetimes," the scientists write in their paper.
One of the exoplanets that they applied the model to was Kepler 22b, which has a habitable lifetime of 4.3 to 6.1 billion years. Another exoplanet, Gliese 581d has a massive habitable lifetime of between 42.4 to 54.7 billion years. It may be warm and pleasant for 10 times the entire time that our solar system has existed.
"To date, no true Earth analogue planet has been detected. But it is possible that there will be a habitable, Earth-like planet within 10 light-years, which is very close in astronomical terms. However reaching it would take hundreds of thousands of years with our current technology," say the researchers.
Courtesy: Astrobiology Scientific Journal
