Does life exist anywhere other than Earth? Scientists aren’t yet certain. But they seem to be on the verge of finding out for sure. The likely answer: Yes.
That’s what is significant about their discovery of the first “Goldilocks” planet, a remote world somewhat like our own circling a dim star in the Libra constellation.
There conditions have been determined to be not too hot, not too cold, but just right to possibly support life.
Known as Gliese 581g, the rocky orb - which is also the right size to have the gravity needed to retain an atmosphere - is the first to be discovered beyond our solar system with the potential to host living organisms.
The unseen planet was located indirectly through telescopic measurements of wobbles in the rotation of its star. Calculations show that it’s a world where there could be liquid water, which is something considered to be necessary for the existence of life.
Temperatures on Gliese 581g can be as hot as 160 degrees Fahrenheit or as cold as 25 degrees below zero. For lack of rotation, one side remains in the light, the other in the dark. At the edges on those two zones, it should be “shirtsleeve weather,” says co-discoverer Steven Vogt.
On the surface of the orb, which is three-to-four times the size of Earth, astronauts could easily walk.
But it’s not as if humans will pay a visit anytime soon to the neighborhood of Gliese 581, the name of the star, or to its g planet, the sixth orbiting in that system.
They are about 20 light years (that is, 118 trillion miles) from Earth. If a spaceship could travel in the far distant future at even one-tenth the speed of light, it would take 200 years to get there.
Yet the discovery of the first Goldilocks planet is Earth-shaking, so to speak.
In terms of astronomy, Gliese 581 is very close to us in the Milky Way and it’s only been 15 years since the first confirmation of any planet beyond our solar system.
The latest discovery leads many scientists to believe that our universe must be teeming with life.
Finding a habitable world in another solar system so near to us and so early in the search indicates that planets like Earth are probably not rare. In fact, it’s estimated that as many as one out of every five-to-10 stars in the universe could have Earth-sized planets in the habitable zone. In just our Milky Way, that would mean perhaps 40 billion planets with the potential for life.
What’s next is actually finding proof of a living organism at any stage of evolution anywhere else - evidence that we are not alone. It’s expected to happen sooner rather than later.