Aging Star Sends Out a Cosmic Valentine

In a cosmic twist, a star has been caught sending out a heart-shaped cloud of dust and gas. This star, Mira A, is not just any star. It's a red giant, and it's part of a binary system with a white dwarf called Mira B. Both stars are located in the constellation Cetus, about 300 light-years from Earth. Mira A is a variable star, meaning its brightness changes over time. Stars like Mira A are known as "Mira variables. " Astronomers have known about Mira A for over 400 years, but recent observations have revealed something unexpected. Between 2015 and 2023, data from the European Southern Observatory's Very Large Telescope and the Atacama Large Millimeter/submillimeter Array showed that Mira A was ejecting material at an astonishing rate. The volume of material released was around 100 times more than expected. This is equivalent to seven times the mass of Earth.The ejected material formed a heart-shaped cloud. Observations in visible light and infrared revealed that two plumes created this cloud. The cloud is filled with gas, but dust is concentrated along its outer edges. Astronomers were surprised by the sheer volume of material released and the speed at which it happened. They also noticed that the star's illumination of the surrounding dust varies in an unexpected way. This makes the star act like a lighthouse, illuminating its environment unevenly. The expanding cloud around Mira A is becoming so large that it may start to affect its companion star, Mira B. Mira B is already gathering some of the material ejected by Mira A. Understanding how Mira A is losing mass provides new insights into how aging stars evolve. This process can shed material that later becomes the building blocks of new star systems.