Astronomers Get to the Heart of Mira A’s Latest Outburst

Just a few hundred light-years from Earth, the famous variable star Mira A is huffing and puffing its outer layers to space. Its most recent mass-loss event ejected more material at higher velocity than in past events. A team of astronomers led by Theo Khouri, Chalmers University in Sweden discovered two large clouds of material expanding away from Mira A in observations done by the Very Large Telescope and ALMA telescopes in South America in 2015 and 2023. Those clouds form two lobes of a cosmic “heart” shape surrounding the star. That structure is basically a cloud of dust at the edges, filled by gas from the star.