NASA Discovers Possible ‘Sibling’ Supernova Remnants From Rare Double Stellar Explosion

NASA scientists say they may have found the first known example of two supernova remnants left behind by stars that once orbited each other, offering new clues about how massive binary star systems evolve and explode.

The findings, presented Wednesday at the 248th meeting of the American Astronomical Society in Pasadena, suggest that two stellar companions ended their lives in separate supernova explosions thousands of years apart, leaving behind overlapping remnants now visible in space.

Researchers used 16 years of observations from NASA’s Fermi Gamma-ray Space Telescope to study a faint supernova remnant known as G189.6+3.3 and its brighter neighbor, the Jellyfish Nebula (IC 443), located about 6,000 light-years from Earth in the constellation Gemini.

Fermi Data Reveals Hidden Supernova Remnant

Lead researcher Miltiadis Michailidis, a postdoctoral fellow in Stanford University’s physics department, said the team found evidence of gamma rays coming from a previously overlooked remnant hidden by the Jellyfish Nebula’s intense emissions.

“Using 16 years of data from NASA’s Fermi Gamma-ray Space Telescope, our analysis uncovered gamma rays associated with a supernova remnant that was hidden in the glare of its neighbor, the Jellyfish Nebula, one of the brightest gamma-ray-emitting supernova remnants known,” Michailidis said.

“There are so many striking connections between the two remnants that we conclude they’re likely related, giving us the first known example of a binary system where both stars have undergone supernova explosions,” he added. The research will be published in a future edition of Nature Communications.

Evidence Points to Exploding Stellar Siblings

Scientists believe the older remnant, G189.6+3.3, exploded first, sending its companion star hurtling through space. Thousands of years later, that surviving star also exploded, creating the Jellyfish Nebula.

The team found several clues linking the two remnants, including overlapping X-ray emissions and a filament of gas connecting them. Researchers say both remnants appear to be interacting with the same molecular cloud system.

“A bright filament of gas lies between the overlapping remnants,” NASA said in a statement. “New observations of this feature reveal that the shock wave from G189.6+3.3 slammed into dense interstellar gas there and dramatically slowed.” The discovery strengthens the case that both remnants came from stars in the same binary system.

Gamma Rays Offer Clues to Cosmic-Ray Acceleration

The study also sheds light on how supernova remnants accelerate particles to nearly the speed of light.

Fermi’s Large Area Telescope detected gamma-ray emissions produced when fast-moving cosmic-ray protons collide with interstellar gas, creating short-lived particles called neutral pions that quickly decay into gamma rays.

Co-author Marianne Lemoine-Goumard of France’s National Centre for Scientific Research said the observations helped establish a physical connection between the remnants.”With Fermi’s LAT instrument, we found gamma-ray emission associated with accelerated protons in the northern part of the fainter remnant,” Lemoine-Goumard said. “If both remnants are interacting with the same structure, then they must share a common distance from us,” she added.

Rare Laboratory for Studying Stellar Evolution

Researchers estimate the Jellyfish Nebula is about 8,000 to 9,000 years old, while G189.6+3.3 could be between 20,000 and 110,000 years old.

Computer simulations involving one million massive binary star systems showed that close stellar pairs can produce dual supernova explosions separated by similar distances and time intervals. The team calculated that the chance of the observed alignment happening by coincidence is less than 1%, further supporting the idea that the remnants are physically related.

“The evidence we’ve compiled, including observations across the spectrum, the chemical and physical properties of the remnants, simulations, and more, paints a compelling picture of a dual supernova event,” Michailidis said. Scientists believe the original stars were at least 20 times more massive than the Sun.

New Insights Into the Lives of Massive Stars

Astronomers say the discovery offers a rare chance to study how massive binary stars exchange matter, evolve, and eventually explode. The Jellyfish Nebula is also considered a candidate “PeVatron,” a natural cosmic accelerator capable of boosting particles to energies high enough to nearly escape the Milky Way galaxy.

NASA Fermi project scientist Elizabeth Hays said the discovery highlights the mission’s ability to uncover the hidden histories of stars. “Fermi’s gamma-ray observations of supernova remnants continue to reveal the dynamic lives of stars,” Hays said. “We can now connect the glowing remains of two massive stars to a powerful pair that evolved together over thousands of years,” she added.

Scientists say the unusual Jellyfish Nebula-G189.6+3.3 system could become an important laboratory for studying particle acceleration, gamma-ray production, and the evolution of massive binary stars long after their explosive deaths.