When scientists examine distant stars with planets in their orbit, determining the pull of gravity at the surface of the star is one of the key factors that can help them determine whether these planets possess the potential for life. Now, researchers from The University of British Columbia have found a way to measure this gravitational pull, opening up the potential to more easily determine the chance for thriving life on extraterrestrial planets.
The new method explored in the paper allows scientists to determine the surface gravity of a star with an accuracy of approximately four percent for stars that are too distant to be measured by currently available techniques. The surface gravity of a star is essentially the value of your weight if you were standing on the star, if stars possessed solid surfaces that allowed for it. However, your weight would change depending on the mass and radius of the star.
The new technique, referred to as the autocorrelation function timescale technique, will allow astronomers to better measure the masses and sizes of stars in distant galaxies and will help scientists better understand their basic properties.
"If you don't know the star, you don't know the planet," Jaymie Matthews, co-author of the study, said in a press release. "The size of an exoplanet is measured relative to the size of its parent star. If you find a planet around a star that you think is sun-like but is actually a giant, you may have fooled yourself into thinking you've found a habitable Earth-sized world. Our technique can tell you how big and bright is the star, and if a planet around it is the right size and temperature to have water oceans, and maybe life."
Future space missions will require the most accurate information regarding exoplanet stars that they can get and this new technique will likely play a huge role in gathering this information and effectively uncovering the characteristics of new planets.
"The timescale technique is a simple but powerful tool that can be applied to the data from these searches to help understand the nature of stars like our sun and to help find other planets like our Earth," said Thomas Kallinger, lead author of the study.
The findings were published in the Jan. 1 issue of Science Advances.
