Seems like there's more speculation than science.
Our governemnt has been lying for decades about UFO’s. You can’t trust anything NASA says.
John
There could be a good basis for these things. We roughly know what mass the star is since we know it’s luminosity and its distance. In turn, we can tell what the planet’s mass is by the motion of Gleise around their mutual centers of gravity. The orbital period is simply the time it takes for the star to make a single complete “wobble.”
This takes a bit of computation since the wobble we want to measure has to be sifted out from the larger effects of the larger Neptune class planet, but it can be done without too much hassle. Since we know the distance from the star, the star’s energy output, and the planet’s mass, we can say whether or not the world lies in the “habitable zone” wherein liquid water can exist in an equilibrium environment.
The presence of water is suspected on account of current models of the growth and evolution of planetary systems. We won’t know for sure until one of the proposed next-generation spectrometers is launched, but that seems more likely now that we have a definite target, and one that’s pretty close by to boot!