Proxima Centauri b Proxima Centauri b Proxima Centauri b (also called Proxima b or Alpha Centauri Cb) is an exoplanet orbiting in the habitable zone of the red dwarf star Proxima Centauri, which is the closest star to the Sun and part of a triple star system. It is located about 4.2 light-years (1.3 parsecs, 40 trillion km, or 25 trillion miles) from Earth in the constellation of Centaurus, making it the closest known exoplanet to the Solar System. Proxima Centauri b orbits the star at a distance of roughly with an orbital period of approximately 11.2 Earth days, and has an estimated
Expansion of the universe an observer it appears that space is expanding and all but the nearest galaxies are receding into the distance. During the inflationary epoch about 10 of a second after the Big Bang, the universe suddenly expanded, and its volume increased by a factor of at least 10 (an expansion of distance by a factor of at least 10 in each of the three dimensions), equivalent to expanding an object 1 nanometer (10 m, about half the width of a molecule of DNA) in length to one approximately 10.6 light years (about 10 m or 62 trillion miles) long. A much