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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
October 18, 2026
Oct. 17, 2026 NASA’s Nancy Grace Roman Space Telescope has exceeded expectations after engineers made incredibly tiny adjustments to sharpen its view of the universe. By moving a mirror just one-sixteenth the width of a human hair, the team helped bring its ...
Oct. 16, 2026 SpaceX just delivered some surprisingly strange cargo to the International Space Station, including tiny brain models, 3D heart tissue, and technology for making artificial retinas in space. ...
Oct. 12, 2026 Europe's Sentinel-3C satellite has returned breathtaking images of Earth just two weeks after launch, revealing the snowy Alps, frozen Arctic islands, and brilliant turquoise Caribbean waters. Its ...
Oct. 10, 2026 Scientists in Vienna have achieved a major breakthrough in timekeeping by creating the world’s first self-stabilizing nuclear clock, a technology that could eventually surpass even the most precise atomic clocks. Instead of relying on electrons in ...
Oct. 8, 2026 NASA is preparing for humanity’s first Moon base with three investigations that will hunt for underground shelters, uncover hidden ice, and track dangerous conditions on the lunar surface. The findings could reveal how astronauts can survive and ...
Oct. 7, 2026 Earth’s center of mass is constantly on the move, shifting by a few millimeters as enormous amounts of water, ice, and even air migrate around the planet with the seasons. NASA scientists have developed a more precise way to track these tiny ...
Oct. 5, 2026 NASA has selected the GIMLI project to investigate whether the Marius Hill Pit opens into a vast underground cave or lava tube. Using radar, seismic sensors, gravity measurements, and cameras, researchers will search beneath the lunar surface and ...
Oct. 4, 2026 A meteor crater buried beneath Oklahoma has turned out to be nearly 100 million years younger than scientists thought. Zircon crystals show the Ames impact occurred about 370 million years ago, meaning it was not part of the mysterious Ordovician ...
Oct. 3, 2026 Ultra-detailed simulations are showing how the first stars lit up the dark Universe and seeded space with elements such as carbon, oxygen, and iron. The MEGATRON project could bridge JWST observations of the earliest galaxies with chemical clues ...
Oct. 2, 2026 NASA’s Roman Space Telescope has demonstrated remarkable pointing stability and given its powerful planet-imaging coronagraph its first look at the cosmos. The telescope can already stay locked on a target with precision comparable to aiming a ...
Sep. 28, 2026 CosmoCube will use the far side of the Moon as a shield from Earth’s radio noise to search for a faint signal from the universe before the first stars existed. The suitcase-sized satellite could reveal how the cosmic dark ages ended and how dark ...
Sep. 28, 2026 Spaceflight may dramatically change the gut within weeks, causing bacteria to break down more protein as food moves more slowly through the intestines. The shift could help explain astronaut constipation and may have wider effects on health, making ...
Latest Headlines
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Oct. 18, 2026 Astronomers have uncovered compelling evidence of two supermassive black holes spiraling toward a potentially spectacular collision at the center of galaxy Mrk 501. A previously unseen jet of ...
Oct. 17, 2026 A SpaceX Falcon 9 rocket created a dazzling, jellyfish-shaped glow across the eastern United States as sunlight illuminated its exhaust during an early morning launch. The mission delivered equipment ...
Oct. 17, 2026 NASA’s James Webb Space Telescope has revealed that a turbulent world 20 light-years away has a surprisingly orderly weather system, with three ...
Oct. 16, 2026 Astronomers using the James Webb Space Telescope have discovered that a distant alien planet's atmosphere is surprisingly lopsided. Located 1,300 light-years away, the scorching gas giant WASP-17b ...
Oct. 16, 2026 Scientists have discovered that black holes of vastly different sizes appear to launch powerful jets according to the same universal rule. The breakthrough could explain why some black holes suddenly ...
Oct. 14, 2026 Scientists may have solved a long-standing mystery about why the Moon’s two sides are so different, using samples collected from its farside for the first time. Their findings suggest that uneven ...
Oct. 13, 2026 Astronomers have discovered that a scorching-hot planet 320 light-years away shares a striking chemical similarity with its host star, providing the first direct evidence for a fundamental assumption ...
Oct. 13, 2026 NASA’s James Webb Space Telescope has revealed an ancient galaxy cluster with an unexpectedly dense concentration of dark matter, challenging ...
Oct. 11, 2026 An astronaut aboard the International Space Station photographed a remarkable formation in Madagascar that looks surprisingly similar to the Moon’s bright highlands. Made of anorthosite, a rock ...
Oct. 10, 2026 Astronomers have discovered a bizarre star system about 300 light-years from Earth where a small star is slowly devouring a nearby brown dwarf, an object too massive to be a planet but too small to ...