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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
November 25, 2025
Nov. 23, 2025 A massive solar storm in May 2024 gave scientists an unprecedented look at how Earth’s protective plasma layer collapses under intense space weather. With the Arase satellite in a perfect observing position, researchers watched the plasmasphere ...
Nov. 21, 2025 New observations show that asteroid 1998 KY26 is a mere 11 meters across and spinning twice as fast as previously thought. The discovery adds complexity to Hayabusa2’s 2031 mission but also heightens scientific interest. The asteroid’s ...
Nov. 17, 2025 Scientists built a tiny clock from single-electron jumps to probe the true energy cost of quantum timekeeping. They discovered that reading the clock’s output requires vastly more energy than the clock uses to function. This measurement process ...
Nov. 16, 2025 Researchers combined deep learning with high-resolution physics to create the first Milky Way model that tracks over 100 billion stars individually. Their AI learned how gas behaves after supernovae, removing one of the biggest computational ...
Nov. 16, 2025 Dark matter may be invisible, but scientists are getting closer to understanding whether it follows the same rules as everything we can see. By comparing how galaxies move through cosmic gravity wells to the depth of those wells, researchers found ...
Nov. 13, 2025 Researchers engineered “gyromorphs,” a new type of metamaterial that combines liquid-like randomness with large-scale structural patterns to block light from every direction. This innovation solves longstanding limitations in quasicrystal-based ...
Nov. 13, 2025 Arctic sea ice is disappearing fast, and scientists have turned to an unexpected cosmic clue—space dust—to uncover how ice has changed over tens of thousands of years. By tracking helium-3–bearing dust trapped (or blocked) by ancient ice, ...
Nov. 10, 2025 New research from UBC Okanagan mathematically demonstrates that the universe cannot be simulated. Using Gödel’s incompleteness theorem, scientists found that reality requires “non-algorithmic understanding,” something no computation can ...
Nov. 2, 2025 A team of astronomers used the James Webb Space Telescope to create the first 3D atmospheric map of an exoplanet. The fiery WASP-18b, a massive “ultra-hot Jupiter,” revealed striking temperature contrasts, including regions so hot they destroy ...
Oct. 30, 2025 Scientists have developed a groundbreaking tool called Effort.jl that lets them simulate the structure of the universe using just a laptop. The team created a system that dramatically speeds up how researchers study cosmic data, turning what once ...
Oct. 29, 2025 Tohoku University researchers have found a way to make quantum sensors more sensitive by connecting superconducting qubits in optimized network patterns. These networks amplify faint signals possibly left by dark matter. The approach outperformed ...
Oct. 27, 2025 Two Sydney PhD students have pulled off a remarkable space science feat from Earth—using AI-driven software to correct image blurring in NASA’s James Webb Space Telescope. Their innovation, called AMIGO, fixed distortions in the telescope’s ...
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Nov. 24, 2025 Moss spores survived an extended stay on the outside of the ISS and remained capable of germinating once back on Earth. Their resilience to vacuum, extreme temperatures, and UV radiation surprised ...
Nov. 23, 2025 About 4.5 billion years ago, a colossal impact between the young Earth and a mysterious planetary body called Theia changed everything—reshaping Earth, forming the Moon, and scattering clues across ...
Nov. 23, 2025 Scientists flew the XL-Calibur telescope on a high-altitude balloon to measure polarized X-rays from Cygnus X-1. These measurements reveal details about the chaotic, superheated material swirling ...
Nov. 23, 2025 Researchers have pinpointed a super-Earth in the habitable zone of a nearby M-dwarf star only 18 light-years away. Sophisticated instruments detected the planet’s gentle tug on its star, hinting at ...
Nov. 22, 2025 New measurements of radio galaxies reveal that the solar system is racing through the universe at over three times the speed predicted by standard cosmology. Using highly sensitive data from multiple ...
Nov. 20, 2025 Scientists may finally be closing in on the origins of two colossal, mysterious structures buried nearly 1,800 miles inside Earth—hidden formations that have puzzled researchers for decades. New ...
Nov. 18, 2025 Cutting-edge simulations show that Enceladus’ plumes are losing 20–40% less mass than earlier estimates suggested. The new models provide sharper insights into subsurface conditions that future ...
Nov. 16, 2025 Astronomers have, for the first time, recorded the moment a star’s explosion broke through its surface. The nearby supernova, SN 2024ggi, revealed a surprisingly olive-shaped blast when studied ...
Nov. 16, 2025 The “Seven Sisters” have far more relatives than anyone imagined. Using NASA and ESA space telescopes, astronomers found thousands of hidden ...
Nov. 16, 2025 LHAASO has uncovered that micro-quasars, black holes feeding on companion stars, are powerful PeV particle accelerators. Their jets produce ultra-high-energy gamma rays and protons that exceed ...