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    In a first, an image shows a dying star exploded twice to become a supernova 

    For the first time, astronomers have spotted a star that exploded not once, but twice. A new image of a roughly 300-year-old supernova provides visual evidence that some dying stars undergo a double explosion, researchers report July 2 in Nature Astronomy.

    Supernovas usually mark the death of massive stars. But medium-sized ones, like the sun, can also go out with a bang. When midsize stars exhaust their hydrogen fuel, they shed everything but their core, leaving behind small inert objects called white dwarfs. These incredibly dense remnants are about the size of Earth with roughly the mass of the sun. More

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    A newly discovered interstellar object might predate the solar system

    The solar system’s newest visitor, 3I/ATLAS, may be 3 billion years older than the sun and its planets.

    First discovered on July 1, 3I/ATLAS is a rare interstellar object — only the third ever spotted. Since then, astronomers have been racing to uncover its origins. A new calculation predicts that 3I/ATLAS originated from a part of the Milky Way called the thick disk. If so, there’s a two-thirds chance that it’s a comet over 7 billion years old. That would make it the oldest comet known, researchers reported July 11 at the Royal Astronomical Society’s National Astronomy Meeting 2025 in Durham, England. More

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    A third visitor from another star is hurtling through the solar system

    For only the third time in history, astronomers have detected a new interstellar visitor — an object from another star — blitzing into our solar system.

    First named A11pl3Z and now designated as 3I/ATLAS , the comet was spotted by a survey telescope in Chile on July 1 and confirmed by the International Astronomical Union’s Minor Planet Center the same day. To piece together its trajectory, astronomers dug through older sky surveys and found its position as early as mid-June. More

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    A barrage of radiation couldn’t kill this hardy life-form

    An unassuming lichen harbors a hidden superpower: It’s remarkably resistant to ultraviolet radiation. New experiments on the hardy organism call into question the long-held belief that alien planets bathed in ultraviolet light must be sterile worlds, researchers report June 12 in Astrobiology. The discovery may open up more options in the search for life elsewhere in the universe.

    Thousands of exoplanets have been discovered to date, but many of them orbit a type of small, highly active star apt to send off blasts of energetic particles and radiation. And unlike our planet, those worlds likely don’t have ozone in their atmospheres. Ozone is formed from compounds produced by photosynthesis, and researchers haven’t found any evidence of such a process occurring on an exoplanet. More