The cosmic explosion that marks the end of a star’s life has long been a topic of fascination for astronomers. For the first time, scientists have captured visual evidence of a star meeting its end by detonating twice. The remains of supernova SNR 0509-67.5, studied with the European Southern Observatory’s Very Large Telescope (ESO’s VLT), show patterns that confirm its star suffered a pair of explosive blasts.

The explosions of white dwarfs play a crucial role in astronomy. Much of our knowledge of how the Universe expands rests on Type Ia supernovae, and they are also the primary source of iron on our planet, including the iron in our blood. However, despite their importance, the exact mechanism triggering these explosions remains unsolved.

All models that explain Type Ia supernovae begin with a white dwarf in a pair of stars. If it orbits close enough to the other star in this pair, the dwarf can steal material from its partner. In the most established theory behind Type Ia supernovae, the white dwarf accumulates matter from its companion until it reaches a critical mass, at which point it undergoes a single explosion.

However, recent studies have hinted that at least some Type Ia supernovae could be better explained by a double explosion triggered before the star reached this critical mass. This alternative model suggests that the white dwarf forms a blanket of stolen helium around itself, which can become unstable and ignite. This first explosion generates a shockwave that travels around the white dwarf and inwards, triggering a second detonation in the core of the star — ultimately creating the supernova.

Until now, there had been no clear, visual evidence of a white dwarf undergoing a double detonation. Recently, astronomers have predicted that this process would create a distinctive pattern or fingerprint in the supernova’s still-glowing remains, visible long after the initial explosion. Research suggests that remnants of such a supernova would contain two separate shells of calcium.

Astronomers have now found this fingerprint in a supernova’s remains. Ivo Seitenzahl, who led the observations and was at Germany’s Heidelberg Institute for Theoretical Studies when the study was conducted, says these results show “a clear indication that white dwarfs can explode well before they reach the famous Chandrasekhar mass limit, and that the ‘double-detonation’ mechanism does indeed occur in nature.”

The team were able to detect these calcium layers (in blue in the image) in the supernova remnant SNR 0509-67.5 by observing it with the Multi Unit Spectroscopic Explorer (MUSE) on ESO’s VLT. This provides strong evidence that a Type Ia supernova can occur before its parent white dwarf reaches a critical mass.

Type Ia supernovae are key to our understanding of the Universe. They behave in very consistent ways, and their brightness allows them to be seen from vast distances. By studying these cosmic events, scientists gain insights into the life cycles of stars and the evolution of the cosmos itself.

The discovery of a double-detonation mechanism in Type Ia supernovae has significant implications for our understanding of the Universe. It suggests that these explosions can occur at different stages of a star’s life, potentially leading to new observations and a deeper understanding of the cosmic web.

As scientists continue to study the remnants of supernova SNR 0509-67.5, they may uncover more secrets about the double-detonation mechanism and its role in shaping the Universe. The findings of this research have far-reaching implications for our understanding of the cosmos and the life cycles of stars.

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In the vast expanse of space, Earth’s limitations no longer apply. That’s exactly where University of Florida (UF) engineering associate professor Victoria Miller, Ph.D., and her students are pushing the boundaries of what’s possible.

In partnership with the Defense Advanced Research Projects Agency (DARPA) and NASA’s Marshall Space Flight Center, UF’s engineering team is exploring how to manufacture precision metal structures in orbit using laser technology. The project, called NOM4D – Novel Orbital and Moon Manufacturing, Materials, and Mass-efficient Design – seeks to transform how people think about space infrastructure development.

“We want to build big things in space,” said Miller. “To build big things in space, you must start manufacturing things in space. This is an exciting new frontier.”

Imagine constructing massive structures like satellite antennas, solar panels, or even parts of space stations directly in orbit. That’s exactly what Miller’s team aims to achieve with their pioneering research.

UF received a $1.1 million DARPA contract to carry out this work over three phases. While other universities explore various aspects of space manufacturing, UF is the only one specifically focused on laser forming for space applications, according to Miller.

A major challenge of the NOM4D project is overcoming the size and weight limitations of rocket cargo. To address these concerns, Miller’s team is developing laser-forming technology to bend metals into precise shapes without human touch. This process involves tracing patterns on metals with a laser beam, which heats and bends them into shape.

“With this technology, we can build structures in space far more efficiently than launching them fully assembled from Earth,” said team member Nathan Fripp, also a third-year Ph.D. student studying materials science and engineering. “This opens up a wide range of new possibilities for space exploration, satellite systems, and even future habitats.”

However, the challenge doesn’t stop at shaping metals; Miller’s students are also working to ensure that material properties remain good or improve during the laser-forming process.

“The challenge is ensuring that the material properties stay good or improve during the laser-forming process,” said Miller. “Can we ensure when we bend this sheet metal that bent regions still have really good properties and are strong and tough with the right flexibility?”

To analyze the materials, students ran controlled tests on aluminum, ceramics, and stainless steel, assessing how variables like laser input, heat, and gravity affect how materials bend and behave.

“We run many controlled tests and collect detailed data on how different metals respond to laser energy: how much they bend, how much they heat up, how the heat affects them, and more,” said team member Tianchen Wei, a third-year Ph.D. student in materials science and engineering. “We have also developed models to predict the temperature and the amount of bending based on the material properties and laser energy input.”

The research has made significant progress since 2021, but the technology must be further developed before it’s ready for use in space. Collaboration with NASA Marshall Space Center is critical, enabling researchers to test laser forming in space-like conditions inside a thermal vacuum chamber provided by NASA.

As the project enters its final year, finishing in June of 2026, questions remain around maintaining material integrity during the laser-forming process. Still, Miller’s team remains optimistic that UF moves one step closer to a new era of construction with each simulation and laser test.

“It’s great to be a part of a team pushing the boundaries of what’s possible in manufacturing, not just on Earth, but beyond,” said Wei.

The article highlights the groundbreaking discovery made by citizen scientists participating in the Kilonova Seekers project. This initiative allows members of the public to analyze near-real-time data collected from the Gravitational-wave Optical Transient Observer (GOTO) project, which involves two arrays of telescopes located on opposite sides of the planet.

The team, led by Dr. Tom Killestein and Dr. Lisa Kelsey, was able to identify a bright exploding star, dubbed GOTO0650, after public volunteers flagged it as an object of interest within 3.5 hours of the image being taken. The quick response enabled the team to gather an unusually complete dataset on the star, including spectroscopy, X-ray, and UV measurements.

The discovery was made possible by the involvement of citizen scientists from around the world, who were able to analyze images and data in real-time. One volunteer, Svetoslav Alexandrov, recalled his excitement when he saw that he would be a co-author on the research paper, while another, Cledison Marcos da Silva, credited the project with distracting him from a serious health problem.

The article concludes by emphasizing the importance of citizen science in making novel serendipitous discoveries in vast datasets. The Kilonova Seekers project is approaching its two-year anniversary and has provided over 3,500 members of the public with the opportunity to discover supernovae and variable stars using real data.

In summary, the article showcases the power of collaborative efforts between scientists and citizens, highlighting the potential for groundbreaking discoveries in real-time. The image prompt complements the article by visually representing the excitement and wonder of uncovering a rare exploding star, surrounded by the diverse group of scientists working together to understand this phenomenon.