For years, astronomers have observed the stars, wondering whether storms as violent as those that shake the Sun could erupt elsewhere in the universe. The Sun often hurls gigantic clouds of plasma into space — known as coronal mass ejections (CMEs) — capable of disrupting space weather, creating dazzling auroras, or rattling the satellites orbiting Earth. But beyond the Sun, no one had ever observed another celestial body doing the same… until now. An international team of astronomers, combining the sharp vision of the LOFAR radio telescope with the European Space Agency’s (ESA) XMM-Newton space observatory, has for the first time detected a massive stellar explosion on a star outside our cosmic neighborhood, the solar system.
The star at the center of this event is a red dwarf named StKM 1-1262, located about 40 light-years from Earth, according to a new study published Wednesday in Nature. Smaller and cooler than the Sun, the star unleashed an eruption consisting of a burst of radio waves — essentially extremely powerful and brief energy flashes — that traveled across space, indicating that a colossal magnetized plasma ejection had erupted from its surface.
“The magnetic explosion occurred in 1883, and the light from that event only reached us in 2016, when we detected it,” Cyril Tasse, a researcher at the Paris Observatory in France and co-author of the discovery, told EL PAÍS.
The study covered the northern hemisphere sky, and analyzed each region for eight continuous hours. When a stellar CME moves from the corona (the outermost layer of its atmosphere) into space, it generates a shock wave. The recent research indicates that the explosion was so violent that any nearby planet would likely have lost its entire atmosphere. Tasse recalls that the ejection lasted about a minute.
“The star was in that position, so there wasn’t really much discussion. We knew it was an explosion,” he adds.
The discovery was not a matter of luck. Behind that lone burst lies years of meticulous work and advanced technology. It was precisely the plasma’s “cry” that LOFAR, the network of antennas spread across Europe designed to capture the lowest frequencies of the sky, ultimately detected. According to scientists, a signal like this would not exist unless the material had been completely ejected from the star’s magnetic bubble.
To estimate the phenomenon’s magnitude, the researchers applied models similar to those used to study the Sun, but adapted to the conditions of this red dwarf. They developed a technique to study all the stars in the field of view simultaneously, which Tasse compares to casting a fishing net into the sea “to try to catch as many fish as possible.” Measurements revealed that the expelled plasma traveled at about 2,400 kilometers per second. Without this data analysis technique, developed at the Paris Observatory, it would have been impossible to detect the star.
Such speeds — unthinkable for most solar eruptions — are only seen in the Sun’s most extreme events, though a shock of this type has never occurred. If it did, humanity would be in serious danger. Despite the red dwarf having roughly half the Sun’s mass, rotating 20 times faster, and possessing a magnetic field 300 times stronger, events in this type of star can be far more frequent and intense.
Most known exoplanets orbit stars like StKM 1-1262, making these findings crucial for understanding our galaxy. Benjamín Montesinos, an astrophysicist at Spain’s Center for Astrobiology (CSIC), notes that red dwarfs were already known to have strong magnetic activity, especially when young. “Until now, flares had been observed in X-ray, ultraviolet, and optical wavelengths. The novelty is the detection in radio, which complements those observations and allows direct comparison with solar phenomena,” says Montesinos, who was not involved in the study.
A magnetic monster
The discovery raises serious questions about the habitability of worlds orbiting red dwarfs, the most common stars in the Milky Way and hosts to most known exoplanets. A planet constantly bombarded by powerful CMEs could lose its entire atmosphere, and be reduced to a barren, uninhabitable rock. Cyril Tasse explains: “For liquid water to exist on a planet’s surface, the temperature must remain suitable, and that depends on the greenhouse effect. This happens when the atmosphere traps some of the energy from the star.”
But receiving the right amount of light is not enough; an atmosphere that retains heat is also necessary. “The holy grail for researchers now is to find Earth-like planets orbiting stars similar to the Sun,” adds Montesinos.
The new study also expands understanding of space weather in general, a research area the European Space Agency has followed for decades. Launched in 1999, XMM-Newton has been key for studying the universe’s extreme environments — from galactic cores to radiation bursts from distant stars and galaxies. Tasse revealed that his team has detected other types of signals: “We believe we are seeing auroras on exoplanets, in radio waves, which is interesting.”
It is not just the Sun that hurls fire into the void. Other stars do it too. And this discovery, more than a mere astronomical observation, opens a new window for understanding how life on surrounding worlds is forged — and how it might be simultaneously extinguished.
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