Proxima Centauri Just Became Our Gateway to the Cosmos

Astrogeology, Asteroids, Robots, Space Flight & Extraterrestrial Matters

Date posted: 09/03/16

Dr. Scharf opines that when astronomers obtain convincing evidence of a potentially habitable world around our nearest neighboring star, this could change everything. In this golden age of exoplanetary science, the announcement of a planet 30% more massive than the Earth, in an 11.2 day orbit around a low-mass star with a luminosity 0.15% of the Sun would usually elicit little more than a raised eyebrow. Except for the fact that this world orbits the nearest star to ours ... Proxima Centauri. It means that at a cosmically trifling 24 trillion miles (4.243 light years) from where you are at this instant is an alien system with a planet that could conceivably harbor life as we know it. That planet is estimated to be around 4.9 billion years old, it receives about 65% of the Earth stellar irradiation, and its skies, whatever else is in them, are bathed in the red-hued rays of a diminutive star only 12% the mass of our Sun. Planets have been upending our preconceptions about the nature of the universe for a long time. Over the centuries, as science and western culture came to accept a heliocentric solar system governed solely by physics, we have also (mostly) accepted a larger and larger version of reality, of which we are a smaller and smaller part. Although this expanding view of an expanding cosmos has led to speculations about who or what else might be out there in the surrounding universe, most of us have also been remarkably good at pushing these questions to the back of our minds. As a species, we have had plenty of other pressing things to worry about. We are also still hominids that like lower hanging fruit, be they edible or intellectual. The fact that it was not until the 1990s that we finally confirmed the existence of planets around other stars is evidence for that tendency (or at least evidence that most scientists only jump onto bandwagons once they are comfortably rolling).