|Photo: Randy Shore|
At least a dozen “Goldilocks” planets have already been identified, worlds that are neither too hot, nor too cold, but just right for liquid oceans and to support life as we understand it.
But deciding whether a planet is likely to support life depends on the properties of the star that it orbits. Knowing its surface gravity reveals its size, energy output and the size of the planets in its system.
|Photo: Jaymie Mark Matthews|
Remember the fable The Boy Who Cried Wolf? No astronomer wants to be The Boy Who Cried Earth and later has to say ‘Never mind. My bad.’”
Scientists can use established methods to measure surface gravity of bright stars that are relatively close by, but that leaves out about a billion trillion stars and their planets.
“Whether we first find life on a planet 50 light years away or 5,000 light years away, the distance of the planet will be a footnote in the history books,” said Matthews. “The headline will be ‘We found life!’”
Matthews and study co-author Thomas Kallinger have found a way to use the subtle variations in the brightness of distant stars caused by convection and surface turbulence — like a boiling pot of soup — to calculate surface gravity...
The details of the autocorrelation time scale technique appear in the journal Science Advances.
Science Advances 01 Jan 2016:
Vol. 2, no. 1, e1500654
Source: Vancouver Sun