As a new step towards finding the fact whether the planets revolving around in the universe are capable of supporting life or not, scientists have been able to found a new way to measure gravitational pull of distant stars. The new technique, dubbed as the autocorrelation function timescale technique, would have implications in findings habitable planets beyond our solar system. Measuring surface gravity means to determine how much weight a person carries on a star and it varies from star to star. Scientists said that a person weighs 20 times more on the sun compared to his weight on Earth.
The new technique takes into account the variations in brightness of distant stars which are observed through satellites like MOST and NASA’s Kepler Space Telescope. Thomas Kallinger, from University of Vienna, said the timescale technique could help understand the nature of stars like our sun and to help find other planets like our Earth. The interesting thing to note is that new technique can help measure surface gravity of distant planets up to 4% accuracy. Surface gravity of a star depends on it mass and radius like our weight on Earth is determined by the mass and radius of Earth. It is usually calculated by measuring a star's light or brightness, but this only works well for the closest, brightest stars.
Jaymie Mathews, from University of British Colombia, said “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-size world”. Jaymie said that the autocorrelation function timescale technique can tell for how big and bright the star is. Moreover, the technique can also help scientists to determine that whether a planet around is the right size and temperature to have oceans and maybe life. The study published in the Journal Science Advances stress the advancement in the astronomy that will help scientists to measure the pull of gravity on a distant star.
In a statement provided to Astronomy, the new method is described in a study published today in Science Advances. The research was led by University of Vienna's Thomas Kallinger and involved UBC Professor Jaymie Matthews as well as astronomers from Germany, France and Australia.
Knowing the surface gravity of a star is essentially knowing how much you would weigh on that star. If stars had solid surfaces on which you could stand, then your weight would change from star to star. The Sun is hotter than a sauna, but don't expect to lose weight there. You'd weigh 20 times more than on Earth. A red giant star (the far-future fate of our Sun) has a much weaker pull at its surface, so you'd be 50 times lighter.
FinancialExpress report said, since surface gravity depends on the star’s mass and radius (just as your weight on Earth depends on its mass and radius), this technique will enable astronomers to better gauge the masses and sizes of distant stars.
“If you don’t know the star, you don’t know the planet. The size of an exoplanet is measured relative to the size of its parent star,” said study co-author and professor Jaymie Matthews from University of British Columbia.
In a statement provided to BGR, in a bid to determine whether distant stars with planets orbiting them can harbour life, a global team of astronomers has discovered a new way to measure the pull of gravity at the surface of distant stars.
Knowing the surface gravity of a star is essentially knowing how much you would weigh on that star. If stars had solid surfaces on which you could stand, then your weight would change from star to star. The new method allows scientists to measure surface gravity with an accuracy of about four percent, for stars too distant and too faint to apply current techniques.