The star Proxima Centauri is invisible to the naked eye, yet it is from this day indelibly associated with the most visible constellation in our skies, the Southern Cross.
Find the two bright pointer stars in the constellation of Centaurus, which point to the stars of the Crux constellation, and the yellow star Alpha Centauri and bright silver star Beta Centauri are obvious.
Yet from today we know that in the apparent void between the pointers, there is a newly discovered planet not much larger than our home planet Earth, orbiting a much dimmer red dwarf star called Proxima Centauri.
As the European team that found the planet carefully makes clear, it isn’t known with certainty if Proxima Centauri is really gravitationally a part of the bright, easily seen yellow star Alpha Centauri, or just drifting past that double star system in a cosmically close encounter.
One of the closely bound stars in Alpha Centauri is similar in size and nature to our solo yellow Sun, while the other is a slightly smaller, more orange-hued star, and they merge at more than four light years’ distance into the single bright star we see as the yellow pointer to the Southern Cross.
If there are planets around either or both of the Alpha Centauri stars, Proxima Centauri is still so distant and dim that it would be just another star in their night skies and much less obvious than our own Sun.
As for the planet, Proxima b, what is it like? We really don’t know. It orbits its red dwarf star at very close range, closer than Mercury is to our Sun, but it would receive enough radiant energy to put it within the so called Goldilocks Zone, where liquid water could exist on its surface.
Depending on whether the planet rotates faster on its axis than it rotates around the red dwarf, any seas might be swept by massive tides, but there are so many potential factors or moving parts in such visualisations that almost anything is possible.
It might be a barren rocky planet, or a water world, or anything in between, or beyond our imaginings, given there is so little hard information at hand. Since red dwarf stars can turn “angry” and throw off massive energetic flares, it might not even have a long-term atmosphere, since such eruptions could blast it away at geological intervals.
Life as we know it might flourish below its surface or in the depths of any seas. Or it might have never originated under the destructive anvil of an angry red dwarf.
Will we ever know the answers to some of these questions or possibilities? That’s highly likely as new generations of space telescopes allow the detection of any atmosphere around such “exoplanets” (of which thousands have now been discovered) and find any signs of biological activity.
Our species might even see Proxima b and other exoplanets and their stars close up, if new laser-based technologies allow clouds of “starchips” to be sent at fractions of the speed of light to stars in our galactic neighborhood.
No one who reads this story will live long enough to know. But our children and their children may well find out, if we manage our tenure on planet Earth more wisely than we have.