I've been sitting this one out until today. They first saw this signal in Proxima's light curve in 2000 and had trouble verifying it. It looks like the ESO guys are also being cautious with their wording so I shall also be EXTREMELY cautious and careful with my words here.

POTENTIAL.

Say that with me again. OK? Cool. now let's look at what this discovery is, and how I as an amateur astronomer who does outreach will cover the topic. First, let's talk about Proxima Centauri.

Proxima is a red dwarf, about 12% the mass and size of our sun. It is very dim... in the visible light spectrum. Proxima pumps out as much x-ray radiation as the sun does. It is also a flare star. Every once in a while, the whole surface of Proxima will explode as magnetic lines of force connect and disconnect rapidly. This generates a massive short lived burst of x-rays that can be 100x the normal whole output of the Sun, a star much, much bigger. Think of a coronal mass ejection, only on steroids, multivitamins, herbal supplements and Ovaltine. We are only within the last 10-15 years been able to get a handle on what a red dwarf star is, how they act and evolve, how they bun their fuel, etc. So IF this turns out to be real, that planet is in for some interesting times. Proxima is also an older star that has an age of roughly 5 billion years, or about 10% older than our solar system.

The planet is also very close to the star, 10x closer than Mercury is. Yet this gives it roughly the orbital characteristics of Callisto, the outermost of Jupiter's big moons. So the planet will almost certainly be tidally locked. This means that like our moon has a side that always faces the earth, one side of this planet will always face the star. The only reason we know that this thing exists (POTENTIALLY!) is because we can measure a fluctuation in the light coming from Proxima... this fluctuation is every 11.2 earth days. So if our new neighbor is real, a year on this place will be less than two of our weeks. The 2000 data was also 10.5 days or so. They also think there is another body that has a period of 50 days but they cannot confirm it.

So Ok, let's play the guessing and imagination games.

This planet is slightly bigger than the earth in mass. It is too small to be a "Neptune" sized body, and too small and too hot to be a giant ball of gas. That means we are dealing with a terrestrial world made of metal and rocks. OK, so far I like this. IF this world has a molten core, which at this weight it should, then there is a potential for a magnetic field that might protect the planet from all that x-ray radiation, and may help retain an atmosphere. OK, cool. But at that close, in that environment, water will be broken down and the hydrogen will escape over time. How does that fare for water? Nobody really knows, and until we get the James Webb Telescope up and looking at this thing we don't know. All we have is a sample size of 1 (Our Solar system) to go on. Still a neat find if it can be found with other gear and in other telescopes.

Expect there to be more and more calls for Stephen Hawking's interplanetary probe, though. I hope that gets traction as if they launch it in the next 10 years or so I may live long enough to see at least some of the data from it.