Short answers, pulled from the story.
Proxima Centauri is 4.2465 light-years from the Sun, based on a parallax of 768.0665 published in 2020 in Gaia Data Release 3. It is the nearest star to Earth after the Sun, located in the southern constellation of Centaurus.
Proxima Centauri was discovered in 1915 by Robert Innes, a Scottish astronomer and director of the Union Observatory in Johannesburg, South Africa. He identified it by noticing that the faint star shared the same proper motion across the sky as Alpha Centauri.
As of 2025, Proxima Centauri has two confirmed planets and one candidate. Proxima Centauri b, confirmed in 2016 and orbiting every 11.2 Earth days, sits inside the habitable zone with a minimum mass of at least 1.07 times Earth's. Proxima d, a sub-Earth with a 5.1-day orbit, was independently confirmed by the NIRPS spectrograph in July 2025. A third candidate, Proxima c, remains disputed.
Proxima Centauri b orbits within its star's habitable zone, where liquid water could theoretically exist on its surface. However, habitability is highly uncertain because Proxima is a flare star whose radiation outbursts could erode a planetary atmosphere, and the planet is likely tidally locked, keeping one hemisphere in permanent daylight and the other in permanent night.
Proxima Centauri's interior is completely convective, meaning plasma physically circulates from core to surface, generating a strong magnetic field. Energy from that field is released at the surface as stellar flares. A 2016 superflare increased the star's optical brightness by a factor of 68 times, and a flare on the 6th of May 2019 became the brightest stellar flare ever detected.
Proxima Centauri will remain on the main sequence for roughly four trillion years, far longer than the current age of the universe. Its deep convection allows it to burn nearly all of its hydrogen fuel before eventually evolving into a helium white dwarf, bypassing the red-giant phase.