Researchers put the date of the universe at 13.8 billion years. Astronomers going over four years of data from NASA’s Kepler spacecraft have found that planetary formation didn’t take long after that to get started.
An ancient star has been discovered with at least five Earth-size planets. According to the team of astronomers led by Tiago Campante (University of Birmingham in the UK), the system is 11.2 billion years old.
“We thus show that Earth-size planets have formed throughout most of the Universe’s 13.8 billion-year history, leaving open the possibility for the existence of ancient life in the Galaxy,” reads a part of the published paper.
Kepler-444 sits 117 light years from Earth. But, don’t expect life around the five known planets orbiting the star.
Kepler-444 is 25% smaller than our own sun. And, the planets are generally between Mercury and Venus in size. There’s just one problem. They orbit too close. The five planets complete their orbits around the star in less than 10 days. That would make them hotter than Mercury and not habitable.
While Kepler-444 isn’t the answer for life outside Earth, it does show planetary formation began very soon after the Universe formed.
“This is one of the oldest systems in the galaxy,” says co-author Steve Kawaler, an Iowa State University professor of physics and astronomy.
“Kepler-444 came from the first generation of stars. This system tells us that planets were forming around stars nearly 7 billion years before our own solar system.”
How Kepler Works
Kepler takes extremely precise measurements of changes in brightness. To find planets, astronomers are basically waiting for a long-distance eclipse. We can’t see the planets from these distant star systems unless the planet crosses in front of the star from our view on Earth.
As the planet blocks some of the star’s brightness, astronomers are able to tell how big it is. How long this transit takes tells them how long its orbit is, and its orbit size.
Astronomers used astroseismology to tell how old Kepler-444 is. They studied sound waves from within the star. The changes in the pulsating of the sound waves help tell them the star’s diameter, mass and even age.
The implications of the discovery are pretty big. Just imagine, the planets around Kepler-444 were already as old as Earth is today when Earth first formed. If planets have been around this long, why can’t we find life?
As is the case with Kepler-444, maybe we just aren’t looking in the right place.