Led by a team at the University of Vienna, an international team of astronomers and astrophysicists have devised a way to measure the surface gravity of far-away stars that would help them identify planets that could likely support life.
Stars’ surface gravity determines the “Goldilocks Zone”
Unlike that precocious children’s book character who destroyed the bears home, astronomers view Goldilocks as a positive. I’m sorry if I fail to find the good in someone who breaks into your house on a Sunday morning while you’re out with your family, breaks a bit of furniture, and then eats your food. Astronomers however use Goldilocks as synonymous with “not to hot, not to cold” to determine whether a planet could play host to life, or perhaps more importantly, surface water that would make life a possibility.
In a report published on Jan 1, 2016 in the journal Science Advances, the team explained the technique they are calling autocorrelation function timescale technique. In layman’s terms, that mouthful of a technique takes data recorded by NASA‘s Kepler satellites and Canada’s MOST satellite to look for subtle variations in the brightness of distant stars that evade other techniques. This data allows astronomers to understand the surface gravity of the stars studied in order to determine if planets orbiting said stars could support life.
Why is surface gravity important in determining suitability for life?
When you know the surface gravity of a star you essentially learn what you would weigh on that star assuming there was a solid surface on which you could stand. The new technique that is being used to measure the surface area of stars way beyond present current techniques has an accuracy withing 4% according to the team.
“If you don’t know the star, you don’t know the planet,” said study co-author, University of British Columbia Professor Jaymie Matthews. “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. 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. 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.”
This technique has already been used by the researchers to find over a dozen planets in the Goldilocks Zone. That, however, does not mean life is present.
New technique will allow for the study of billions of trillions of stars
Without a proper survey, it’s very difficult to say how many astronomers went into the field in order to be the person or persons who discover life on a new planet, but I’m sure there are a fair number and Dr. Mattews certainly sounds like one of them.
That heading is not inaccurate, this new technique could allow for the study of billions of trillions of stars located beyond the present techniques for measuring surface area and Mathews believes that this will lead to the discovery of life on an exo-planet.
“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!’”
“I expect someone will announce the discovery of life on an exoplanet within about 20 years,” he said. “Microbes may not be Vulcans, but finding life beyond Earth will be one of the most profound milestones in the history of science, philosophy, theology and human culture.”
If you ever doubt this belief, at least in astronomers, re-watch Steven Spielberg’s “E.T” and try to remember how you felt if you we’re lucking enough to have seen it for the first time when you were a child.