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    In a first, the Webb telescope found a planet by actually ‘seeing’ it

    For the first time ever, the James Webb Space Telescope has discovered an exoplanet by directly imaging it. The newfound world has a mass roughly similar to Saturn and orbits inside the debris disk surrounding a young star named TWA 7, researchers report June 25 in Nature.

    JWST has previously discovered more than 100 planets, mostly through the transit method, in which the telescope watches an exoplanet pass in front of its parent star, causing a brief dimming in the star’s light. Direct imaging — capturing a photo of a star-orbiting exoplanet — is a far more challenging task. More

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    A dwarf galaxy just might upend the Milky Way’s predicated demise

    It may come down to a coin toss as to whether the Milky Way collides with the Andromeda Galaxy within 10 billion years.

    While scientists have previously reported that a convergence was certain, an analysis of the latest data suggests the odds are only about 50 percent, researchers report June 2 in Nature Astronomy. The Milky Way’s largest satellite system — the Large Magellanic Cloud — may be our galaxy’s saving grace, the study shows. More

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    Venus’ tectonics may be actively reshaping its surface

    Things may be moving on Venus’ surface.

    In 1983, researchers discovered that the planet’s surface was speckled with strange, circular landforms. These rounded mountain belts, known as coronae, have no known Earthly counterparts, and they’ve remained enigmatic for decades. But hot plumes of rock upwelling from Venus’ mantle are shaping the mysterious landforms, a new analysis suggests. If true, that mean that Venus’ surface is tectonically active, and not merely a stagnant layer, researchers report May 14 in Science Advances. More

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    A passing star could fling Earth out of orbit

    Bad news, earthlings. Computer simulations of the solar system’s future reveal a new risk facing us all: The gravitational tug of a passing star could either cause another planet to smack into Earth or else fling our planet into the sun or far away from it, where any inhabitants would freeze.

    Blame Mercury. Astronomers have long known that the innermost planet’s orbit, which is fairly oval-shaped, can become even more elliptical due to gravitational jiggles from Jupiter. Passing stars exacerbate this danger, Nathan Kaib, an astronomer at the Planetary Science Institute who is based in Iowa, and Sean Raymond, an astronomer at the University of Bordeaux in France, report in work submitted to arXiv.org May 7. More

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    Perseverance takes the first picture of a visible Martian aurora

    On some Martian nights, a subtle, green glow hangs low in the sky, wreathing the horizon in every direction.

    A visible Martian aurora has finally been observed for the first time, researchers report May 14 in Science Advances. The observation, made March 18, 2024, by the Perseverance rover, is also the first of an aurora from the surface of a planet that isn’t Earth. Moreover, it suggests future astronauts may witness ethereal Martian auroras with their own eyes. “It would be a dull or dim green glow to astronauts’ eyes,” says Roger Wiens, a planetary scientist at Purdue University in Lafayette, Ind.

    Auroras can appear when charged particles from space interact with a planet’s atmosphere. They’ve already been spotted on Mercury, Jupiter and every other non-Earth planet in our solar system, but only from orbit. And in Mars’ sky, scientists had only been able to detect auroral wavelengths of light invisible to the naked eye, using instruments. So it wasn’t clear how Martian auroras would appear to future, landed astronauts.

    On March 18, 2024, instruments aboard the Perseverance rover captured an image of a Martian aurora. Though relatively faint, the aurora’s green hues (left) can be made out by comparing the image with one of the typical inky Martian night (right). Due to the phenomenon’s subtle nature, the rover’s instruments were pointed at a low angle over the horizon to peer through a thick layer of the atmosphere. E.W. Knutsen et al/Science Advances 2025

    Compared to many Earthly aurora photos, the new image from Mars is fuzzy. There are a couple reasons for that. First, Perseverance’s cameras perform less well at night, Wiens says. “The instruments aren’t tremendously more sensitive than human eyes,” he says.

    And second, Mars doesn’t have a global magnetic field that concentrates auroras near its poles like Earth does. Instead, its crust is magnetized in patches. That means auroras can appear all over the planet, but they’re relatively dim. More