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Extrasolar planet
An extrasolar planet, or exoplanet, is a planet beyond the Solar System. As of 11 November 2006, 209 extrasolar planets have been discovered.
Known exoplanets are members of planetary systems that orbit a star. There have also been unconfirmed reports of free-floating planetary-mass objects (that is, ones that do not orbit any star). For centuries, extrasolar planets were a subject of speculation. Astronomers generally supposed that some existed, but it was a mystery how common they were and how similar they were to the planets of the Solar System. The first confirmed detections were finally made in the 1990s. Since 2002, more than twenty have been discovered every year. It is now estimated that at least 10% of sunlike stars have planets, and the true proportion may be much higher. The discovery of extrasolar planets raises the question of whether some might support extraterrestrial life.
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Space & Time News
March 10, 2026
Feb. 24, 2026 Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already ...
Feb. 2, 2026 NASA’s Perseverance rover has just made history by driving across Mars using routes planned by artificial intelligence instead of human operators. A vision-capable AI analyzed the same images and terrain data normally used by rover planners, ...
Feb. 2, 2026 Hidden lava tunnels on the Moon and Mars could one day shelter human explorers, offering natural protection from radiation and space debris. A European research team has unveiled a bold new mission concept that uses three different robots working ...
Jan. 28, 2026 Low-Earth orbit is more crowded—and fragile—than it looks. Satellites constantly weave past each other, burning fuel and making dozens of evasive maneuvers every year just to stay safe. A major solar storm could disable navigation and ...
Jan. 19, 2026 Physicists have unveiled a new way to simulate a mysterious form of dark matter that can collide with itself but not with normal matter. This self-interacting dark matter may trigger a dramatic collapse inside dark matter halos, heating and ...
Jan. 18, 2026 When scientists sent bacteria-infecting viruses to the International Space Station, the microbes did not behave the same way they do on Earth. In microgravity, infections still occurred, but both viruses and bacteria evolved differently over time. ...
Jan. 8, 2026 A team of physicists has discovered a surprisingly simple way to build nuclear clocks using tiny amounts of rare thorium. By electroplating thorium onto steel, they achieved the same results as years of work with delicate crystals — but far more ...
Jan. 8, 2026 Nearly everything in the universe is made of mysterious dark matter and dark energy, yet we can’t see either of them directly. Scientists are developing detectors so sensitive they can spot particle interactions that might occur once in years or ...
Jan. 6, 2026 A distant pulsar’s radio signal flickers as it passes through space, much like stars twinkle in Earth’s atmosphere. By monitoring this effect for 10 months, researchers watched the pattern slowly evolve as gas, Earth, and the pulsar all moved. ...
Jan. 6, 2026 Mars looks familiar from afar, but surviving there means creating a protective oasis in a hostile world. Instead of shipping construction materials from Earth, researchers are exploring how to use Martian soil as the raw ingredient. Two tough ...
Jan. 2, 2026 A physicist has proposed a bold experiment that could allow gravitational waves to be manipulated using laser light. By transferring minute amounts of energy between light and gravity, the ...
Dec. 31, 2025 As we age, our immune system quietly loses its edge, and scientists have uncovered a surprising reason why. A protein called platelet factor 4 naturally declines over time, allowing blood stem cells to multiply too freely and drift toward unhealthy, ...
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Mar. 10, 2026 Scientists studying Mars may have uncovered a brand-new mineral hidden in the planet’s ancient sulfate deposits. By combining laboratory experiments with orbital data, researchers identified an ...
Mar. 10, 2026 Cosmic voids may seem like the emptiest places in the universe, stripped of matter, radiation, and even dark matter. But they’re far from nothing. Even in these vast empty regions, the fundamental ...
Mar. 9, 2026 When NASA’s DART spacecraft deliberately crashed into the asteroid moonlet Dimorphos, it did more than change the asteroid’s local orbit — it slightly shifted the path of the entire asteroid ...
Mar. 9, 2026 Astronomers have created the largest and most detailed 3D map yet of a glowing signal from the early universe, revealing hidden galaxies and gas from ...
Mar. 9, 2026 Physicists have long struggled to unite quantum mechanics—the theory governing tiny particles—with Einstein’s theory of gravity, which explains the behavior of stars, planets, and the structure ...
Mar. 8, 2026 Asteroids with tiny moons may be quietly trading material across space. Images from NASA’s DART mission revealed faint streaks on the moon ...
Mar. 6, 2026 For decades, astronomers wondered why most nearby galaxies are speeding away from the Milky Way instead of being pulled in by its gravity. New simulations reveal the answer: our galaxy sits in a ...
Mar. 5, 2026 A sweeping new ALMA image has peeled back the veil on the Milky Way’s core, exposing a dense network of cold gas filaments near the central black ...
Mar. 3, 2026 An international team combining two major neutrino experiments has uncovered stronger evidence that neutrinos and antimatter don’t behave as perfect mirror images. That subtle difference may hold ...
Mar. 3, 2026 A famously resilient bacterium may be tough enough to survive one of the most violent events imaginable on Mars. In laboratory experiments designed to mimic the crushing shock of a massive asteroid ...