For years, scientists have been trying hard to find existence of earth-like planets in our solar system.
And now, researchers at the University of Auckland in New Zealand have come up with a new method for finding planets similar to Earth in Milky Way galaxy and believe that there could be as many as 100 billion of them.
Lead author of the planet search Dr. Phil Yock from the University of Auckland's Department of Physics said his team's strategy is to use a gravitational microlensing technique, currently used by a Japan-New Zealand collaboration called MOA (Microlensing Observations in Astrophysics) at New Zealand's Mt John Observatory. He detailed that the work will require a combination of data from microlensing and the NASA Kepler space telescope.
Kepler spacecraft looks for distant planets by measuring the loss of light from a star when a planet orbits between the earth and the star, whereas microlensing measures the deflection of light from a distant star that passes through a planetary system en route to Earth. This effect was predicted by Albert Einstein in 1936 and has been used successfully to find exoplanets.
"Kepler finds Earth-sized planets that are quite close to parent stars, and it estimates that there are 17 billion such planets in the Milky Way. These planets are generally hotter than Earth," he said, "Our proposal is to measure the number of Earth-mass planets orbiting stars at distances typically twice the Sun-Earth distance. Our planets will therefore be cooler than the Earth."
"By interpolating between the Kepler and microlensing observation results, we should get a good estimate of the number of Earthlike, habitable planets in the Galaxy," he added.
"We anticipate a number in the order of 100 billion. Of course, it will be a long way from measuring this number to actually finding inhabited planets, but it will be a step along the way," he said.
Yock claimed that earth-sized planets could be detected more easily if a worldwide network of moderate-sized, robotic telescopes was available to monitor them.
The work has been published in Monthly Notices of the Royal Astronomical Society.