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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
February 27, 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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Feb. 26, 2026 Scientists at the University of Oxford have finally settled a decades-long mystery about the Moon’s magnetic field — and it turns out both sides were right. By reanalyzing Apollo mission rocks, ...
Feb. 25, 2026 Mars’ frozen ice caps may be time capsules for ancient life. Lab experiments show that key building blocks of proteins can survive tens of millions of years in pure ice, even under relentless ...
Feb. 24, 2026 Deep inside the Milky Way, an invisible force is quietly holding everything together — its magnetic field. Now, researchers have created one of the most detailed maps ever of this hidden structure, ...
Feb. 23, 2026 Far beyond Neptune, in the frozen depths of the Kuiper Belt, many ancient objects oddly resemble giant snowmen made of ice and rock. For years, scientists wondered how these delicate two-lobed shapes ...
Feb. 23, 2026 A Martian volcano once thought to be the result of a single eruption turns out to have a much more complex past. Orbital imaging and mineral data show it developed through multiple eruptive phases, ...
Feb. 21, 2026 For the first time, scientists have mapped Uranus’s upper atmosphere in three dimensions, tracking temperatures and charged particles up to 5,000 kilometers above the clouds. Webb’s sharp vision ...
Feb. 21, 2026 Astronomers have uncovered one of the most mysterious galaxies ever found — a dim, ghostly object called CDG-2 that is almost entirely made of dark ...
Feb. 18, 2026 Researchers have uncovered more than a thousand previously unknown tectonic ridges across the Moon’s dark plains, showing the Moon is still contracting and reshaping itself. These features are ...
Feb. 17, 2026 Scientists scanning the heart of the Milky Way have spotted a tantalizing signal: a possible ultra-fast pulsar spinning every 8.19 milliseconds near Sagittarius A*, the supermassive black hole at our ...
Feb. 16, 2026 New data from major dark-energy observatories suggest the universe may not expand forever after all. A Cornell physicist calculates that the cosmos is heading toward a dramatic reversal: after ...