ALMA Captures New Images of Betelgeuse’s Turbulent Surface Hot Spots

Astronomers using the Atacama Large Millimeter/submillimeter Array have released striking new images of the surface of Betelgeuse, the bright red supergiant in Orion. The pictures reveal a complex pattern of long-lived hot spots and cooler regions across the star’s outer atmosphere.

Betelgeuse has fascinated observers for decades because of its irregular brightness changes and its relatively nearby location—about 650 light-years from Earth. Earlier observations already showed that the star’s surface is not smooth but covered in enormous convective cells. The latest ALMA data resolve these features with unprecedented clarity at millimetre wavelengths.

The hot spots appear to persist longer than simple models of convection predicted. Researchers say the images will help refine simulations of how massive stars lose mass in their final stages and how that material enriches the surrounding interstellar medium. Betelgeuse is expected to end its life as a supernova, though the timing remains uncertain by centuries or more.

The new views arrive as astronomers continue to monitor the star after its dramatic dimming episode in 2019–2020, which was later attributed to a large dust ejection. ALMA’s ability to peer through dust makes it especially well suited to tracking the star’s surface activity over time.

Results such as these remind us that even the brightest naked-eye stars still hold surprises when examined with the right instruments.