Earth-Like Planets May Be Common in Our Galaxy

According to astronomers working with NASA’s Spitzer Space Telescope , terrestrial planets may have formed around many of the sun-like stars in the Milky Way Galaxy. University of Arizona, Tucson, astronomer Michael Meyer and his colleagues used NASA’s Spitzer Space Telescope to determine whether planetary systems like ours are common or rare in our Milky Way galaxy. They found that at least 20 percent, and possibly as many as 60 percent, of stars similar to the sun are candidates for forming rocky planets. The astronomers used Spitzer to survey six sets of stars, grouped depending on their age, with masses comparable to our sun. The sun is about 4.6 billion years old. “We wanted to study the evolution of the gas and dust around stars similar to the sun and compare the results with what we think the solar system looked like at earlier stages during its evolution,” Meyer said.