A New Telescope Still Under Construction Accidentally Reveals How a Dying Star Returns Matter to Space

Researchers captured an unprecedented image of the stellar recycling process while calibrating a Chile-based instrument called MOTHRA, which is expected to be complete by the end of 2026

Sara Hashemi | Daily Correspondent

August 26, 2026 10:00 a.m.

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A partially built telescope in the Chilean Andes has captured an unprecedented image of a dying star shedding its remains and returning them into the galaxy.

Astronomers have long known that when stars die, they release the carbon, oxygen, nitrogen and other elements they’ve made into space. That material then goes on to form new stars, planets and other objects, including us. But actually seeing the expelled star stuff disperse and mix with surrounding interstellar gas proved difficult—until now. 

The observation, described in the journal Nature on August 12, happened by accident. Scientists were calibrating the Modular Optical Telephoto Hyperspectral Robotic Array, or MOTHRA, telescope in November 2025. They pointed it towards the Helix Nebula, a dying star located roughly 650 light-years from Earth, which was an ideal target because it’s large, bright and has been extensively studied.

“We thought we were taking a calibration image of one of the best-known nebulae in the sky,” says study co-author Roberto Abraham, an astronomer at Canada’s University of Toronto, in a statement. “Instead, we found this extraordinary network of bow-shaped structures. It was immediately clear that the faint outer Helix was telling us a story that had largely been missed.”

The image shows 22 complete or partial glowing arcs on the eastern outskirts of the nebula called bow shocks, similar to those that form in the water in front of a moving boat. The ones in space mark where clumps of stellar debris, flung from the star at an estimated 90,000 miles per hour, collided with the surrounding gas and dust of space. The arcs appear only on one side of the astronomical object because the entire structure is traveling at roughly 100,000 miles per hour, the researchers calculated.

The bow shocks closer to the nebula’s faint outer ring—an expelled shell of gas called a halo—are large and sharply defined, while those farther away look fuzzier. That’s probably because the clumps of star material erode and dissolve into the interstellar medium as they travel outward, a process that the team estimates takes about 10,000 years.

“The details of the halo shown in the image are impressive,” says Sun Kwok, an astronomer at the University of British Columbia in Canada who was not involved in the work, to Daniel Clery at Science. Researchers have previously spotted some large bow shocks around the Helix Nebula, he adds, but “these new observations give us insights into the interaction between stellar mass loss and the interstellar medium.”

The new observation offers just a taste of what MOTHRA is capable of. It was captured using fewer than 200 of the planned 1,140 high-end telephoto lenses. Once completed, slated to happen by the end of the year, it’ll use that array of lenses and specialized filters to photograph the faint glow of gas across huge patches of the sky. The researchers tell Mary Randolph at Scientific American that they want to use the instrument to understand how stellar recycling happens for other stars, including our own sun, which is expected to start dying in roughly five billion years.

However, finding similar bow shocks around other nebulae might be challenging, says Kazimierz Borkowski, an astrophysicist at North Carolina State University who was not involved in the study, to Monica Young at Sky & Telescope. The speed at which the Helix Nebula is moving relative to the gas around it means that conditions are favorable for creating visible bow shocks—which might not be happening elsewhere, he explains.

Still, MOTHRA is expected to reveal several surprises about our universe. “This thing is so stupidly powerful that even when you’re building it, all you have to do is point it at anything, and cool things are going to emerge,” Abraham tells K. R. Callaway at the New York Times.

“But we didn’t build this to take pretty pictures. We built it to try and understand how galaxies form and evolve.”

Sara Hashemi is a science writer and fact-checker currently based in New York City. Her work has appeared in Sierra, The Body, Maisonneuve magazine and more.