Free Astronomy Magazine May-June 2025

MAY-JUNE 2025 ing observations with the Atacama Large Millimeter/submillimeter Ar- ray (ALMA) highlights this star’s ex- treme activity in radio and millime- ter wavelengths, offering exciting insights about the nature of these flares as well as potential impacts on the livability of its terrestrial, habit- able-zone planets. Known to host a potentially habit- able planet, the star exhibits very ac- tive flare activity in optical wave- lengths. Like flares on our Sun, these outbursts release light energy across the electromagnetic spectrum and bursts of particles known as stellar energetic particles. Depending on the energy and frequency of these flares, nearby planets in the habit- able zone might be rendered unin- habitable as the flares strip plan- etary atmospheres of necessary in- gredients such as ozone and water. A scientific team led by Kiana Bur- ton of the University of Colorado and Meredith MacGregor of Johns Hopkins University utilized archival data and new ALMA observations ALMA unveils new details of the flares of Proxima Centauri A t just over four light years, Proxima Centauri is our near- est stellar neighbor known to be a very active M dwarf star. Its flare activity has been well known to astronomers using visible wave- lengths of light. Still, a new study us- by ALMA Observatory Nicolás Lira Bárbara Ferreira