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Mercury (planet)
Mercury is the innermost and smallest planet in the solar system, orbiting the Sun once every 88 days. It ranges in brightness from about −2.0 to 5.5 in apparent magnitude, but is not easily seen; its greatest angular separation from the Sun (greatest elongation) is only 28.3° (it can only be seen in twilight). Comparatively little is known about the planet: the only spacecraft to approach Mercury was Mariner 10 from 1974 to 1975, which mapped only 40 to 45 percent of the planet's surface.
Physically, Mercury is similar in appearance to the Moon as it is heavily cratered. It has no natural satellites and no substantial atmosphere. The planet has a large iron core which generates a magnetic field about 1 percent as strong as that of the Earth. Surface temperatures on Mercury range from about 90 to 700 K (-180 to 430°C) , with the subsolar point being the hottest and the bottoms of craters near the poles being the coldest.
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Space & Time News
September 12, 2025
Sep. 11, 2025 — NASA’s Magnetospheric Multiscale Mission has uncovered surprising behavior of pickup ions drifting through the solar wind near Earth. These particles, once thought to be minor players, appear capable of generating waves and influencing how the ...
Sep. 10, 2025 — Physicists have unveiled a new superconducting detector sensitive enough to hunt dark matter particles smaller than electrons. By capturing faint photon signals, the device pushes the search into uncharted ...
Sep. 9, 2025 — Scientists caution that asteroid deflection must be precise, as striking the wrong spot risks sending it through a gravitational keyhole that sets up a future collision with Earth. Using lessons from NASA’s DART mission, researchers are developing ...
Aug. 25, 2025 — Scientists using Google’s quantum processor have taken a major step toward unraveling the deepest mysteries of the universe. By simulating fundamental interactions described by gauge theories, the ...
Aug. 22, 2025 — Astronomers using AI have captured a once-in-a-lifetime cosmic event: a massive star’s violent death triggered by its black hole companion. The explosion, known as SN 2023zkd, not only produced a brilliant supernova but also shocked scientists by ...
Aug. 18, 2025 — NASA and ISRO s NISAR satellite has just reached a major milestone: the successful deployment of its enormous 39-foot antenna reflector in orbit. Folded up like an umbrella during launch, the reflector is now fully extended and ready to support ...
Aug. 18, 2025 — With its two tiny CubeSats, NASA’s PREFIRE mission is capturing invisible heat escaping from Earth, offering clues to how ice, clouds, and storms influence the climate system. The insights could lead to better weather forecasts and a deeper ...
Aug. 17, 2025 — Rising CO₂ levels will make the upper atmosphere colder and thinner, altering how geomagnetic storms impact satellites. Future storms could cause sharper density spikes despite lower overall density, increasing drag-related ...
Aug. 14, 2025 — Thirteen years after landing on Mars, NASA’s Curiosity rover is running smarter and more efficiently than ever. With new autonomy and multitasking capabilities, it’s maximizing the output from its long-lasting nuclear power source while ...
July 27, 2025 — Engineers at the University of Wisconsin-Madison uncovered a critical flaw in how lunar and Martian rovers are tested on Earth. Simulations revealed that test results have been misleading for decades because researchers only adjusted rover weight to ...
July 2, 2025 — UF engineers, backed by DARPA and NASA, are perfecting laser-forming techniques that let metal sheets fold themselves into giant solar arrays, antennas, and even space-station parts right in ...
June 27, 2025 — The LSST camera at the Vera C. Rubin Observatory has released its jaw-dropping first images, each capturing 45 times the area of the full moon in one shot. Over the next ten years, this cosmic giant will scan the southern sky in ultra-HD, helping ...
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Sep. 12, 2025 — Gravitational-wave astronomy has exploded since 2015, capturing hundreds of black hole and neutron star collisions. With ever-clearer signals, researchers are testing Einstein’s relativity and ...
Sep. 11, 2025 — Astronomers have uncovered the violent secret of V Sagittae, a white dwarf star consuming its companion in a spectacular feeding frenzy. This cosmic dance not only makes the system burn with unusual ...
Sep. 11, 2025 — Physicists may soon witness a cosmic fireworks show: the explosive death of a primordial black hole. Once thought to be unimaginably rare, new research suggests there’s up to a 90% chance of ...
Sep. 11, 2025 — Hubble’s latest image captures a glittering star cluster inside the Large Magellanic Cloud, a dwarf galaxy about 160,000 light-years from Earth. This region, known as N11, is one of the galaxy’s ...
Sep. 10, 2025 — Hubble has uncovered a rare ultra-massive white dwarf created in a violent star merger. Once thought to be ordinary, the star’s ultraviolet signature revealed its explosive history and hinted that ...
Sep. 10, 2025 — Astronomers studying an oddball brown dwarf called “The Accident” have finally spotted silane, a long-predicted silicon molecule missing from Jupiter and Saturn’s skies. Its ancient, ...
Sep. 10, 2025 — NASA’s Perseverance rover has discovered mudstones in Mars’ Jezero Crater that contain organic carbon and unusual textures hinting at possible biosignatures. These findings suggest that ancient ...
Sep. 9, 2025 — Saturn’s icy moon Enceladus has long fascinated scientists with its spectacular water plumes, which NASA’s Cassini spacecraft once revealed to contain organic molecules. Many hoped these ...
Sep. 9, 2025 — Astronomers have directly spotted a rare young planet, WISPIT 2b, still forming within the gap of a dusty ringed disk around a star like our sun—something long theorized but never observed until ...
Sep. 7, 2025 — Physicists at the University of Colorado Boulder have created the first time crystal that humans can actually see, using liquid crystals that swirl into never-ending patterns when illuminated by ...