Last Updated Jun 19, 2017 1:27 PM EDT
A detailed analysis of data collected by NASA’s Kepler space telescope has revealed an additional 219 possibleorbiting distant suns, including 10 roughly Earth-size worlds in the habitable zones of their host stars, researchers said Monday.
The analysis pushes Kepler’s tally to 4,034 planet candidates overall, of which 2,335 have been confirmed through additional observation and analysis. More than 30 of 49 terrestrial candidates have been confirmed orbiting in habitable zones where water can exist as a liquid and life as it’s known on Earth could, in theory, exist.
The new Kepler analysis also indicates extra-solar planets form in three general sizes, not two as previously thought. At one extreme are huge-class gas giants. In the middle are roughly Neptune-size worlds and at the other end of the scale are smaller .
“Kepler planets had appeared to span all sizes between one and four times the size of Earth, but when measured precisely, small planets (fall) into two distinct size groups,” said Benjamin Fulton, a researcher at the University of Hawaii and the California Institute of Technology.
“Most of the planets in the first group may be akin to the Earth, with rocky surfaces and little to no atmospheres. Planets in the second group are probably like cousins of Neptune with thick atmospheres and no surface to speak of. Intermediate-size planets between these two size groups are relatively rare.”
The data indicate “a major new division in the family tree of exoplanets,” he said, “somewhat analogous to the discovery that mammals and lizards are separate branches on the tree of life.”
Launched in March 2009,used a…