The closest exoplanet is Proxima Centauri b — just four and a quarter light-years away. Its parent star, Proxima Centauri, is less than one percent as bright as the Sun. Every once in a while, though, it unleashes a huge outburst of energy and particles. And more than two years ago, astronomers saw the most powerful one yet.
Such “superflares” should happen several times a year. And that’s bad news for the planet. If it has an atmosphere, the flares could strip away any ozone atop it, bathing the planet in deadly ultraviolet light. They might even strip away the atmosphere itself.
The flare was observed with Evryscope — a set of a couple of dozen small telescopes in Chile. They’re combined into a single unit that looks like the top of a Star Wars droid.
The system takes a picture of the entire southern sky every two minutes. That allows it to monitor millions of stars. It looks for the stars to flare up. It also searches for exoplanets — looking for a star to grow a tad fainter as a planet passes in front of it.
Many of Evryscope’s target stars also are targets for TESS, NASA’s latest planet-hunting satellite. Astronomers compare results from them to see if a star with planets emits big flares — outbursts that could sterilize the planets.
Project scientists are installing a second cluster of telescopes in California. That’ll allow them to watch the entire night sky.
We’ll talk about another new telescope project tomorrow.
Script by Damond Benningfield