Astronomers have achieved a groundbreaking first: capturing breathtaking footage of a star other than our Sun, revealing giant, boiling bubbles on its surface. Using the powerful Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile, scientists tracked the bubbling gas on R Doradus, a red giant star 180 light-years away. The video shows colossal gas bubbles—some 75 times the size of our Sun—bubbling up, cooling, and sinking back down in a mesmerizing dance that’s happening much faster than scientists ever thought possible.
The research team, led by Wouter Vlemmings from Sweden’s Chalmers University of Technology, describes this achievement as a game-changer in understanding stars. “This is the first time the bubbling surface of a real star can be shown in such a way,” Vlemmings said. The team didn’t expect such incredible detail, which allowed them to watch the star’s convection in action—something previously only seen in the Sun.
Stars like R Doradus are like cosmic lava lamps. Energy created deep within their cores bubbles up to the surface in the form of superheated gas. As these massive bubbles cool down, they sink, carrying vital elements like carbon and nitrogen along with them. This process, called convection, plays a key role in distributing heavy elements throughout the star and eventually out into the universe, where they help form new stars, planets, and even life itself.
Until now, observing such convection in stars other than the Sun was impossible. But ALMA’s high-resolution images have changed that. R Doradus, with its size 350 times that of the Sun, is an ideal candidate for such observations. The star’s massive and strangely fast-moving bubbles cycle on a one-month rhythm—much quicker than expected based on how the Sun behaves. Why this is happening remains a mystery. “We don’t yet know what is the reason for the difference. It seems that convection changes as a star gets older in ways that we don’t yet understand,” Vlemmings noted.
The findings don’t just reveal a dramatic spectacle; they offer a glimpse into our own future. R Doradus’s mass is similar to that of our Sun, giving astronomers a peek at what our own star might look like in about five billion years when it swells into a red giant. “Convection creates the beautiful granular structure seen on the surface of our Sun, but it is hard to see on other stars,” said Theo Khouri, a co-author of the study. Now, with ALMA, the once-unseen motions of these giant convective cells are coming into focus, moving in ways never before observed.
The study, published in Nature, opens up new questions about how stars evolve and why they behave differently as they age. It’s a stunning reminder of the complexity and dynamism of the universe—one that we’re only just beginning to explore.
