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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
October 29, 2026
Oct. 28, 2026 NASA’s Artemis I mission has revealed that cosmic radiation near the Moon is higher than in Earth orbit, but not by as much as scientists might expect. Tiny experimental detectors also uncovered ...
Oct. 21, 2026 Scientists have cracked a 178-year-old mystery surrounding a train delayed by a solar storm, revealing that the famous incident happened in 1848 rather than 1841. The discovery rewrites the early history of space weather and highlights a threat that ...
Oct. 21, 2026 A new study tracking 13 astronauts suggests that the human heart may be surprisingly well equipped for a journey to Mars, especially with regular exercise during spaceflight. Researchers found that astronauts' hearts adapted to months of ...
Oct. 21, 2026 NASA’s Perseverance rover has shattered a historic space exploration record, traveling farther across another world than any vehicle before it. Its advanced self-driving system helped it surpass ...
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 ...
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Oct. 29, 2026 NASA’s Juno spacecraft has discovered that Jupiter uses a surprisingly complex system of powerful plasma waves and multiple shock regions to defend against the solar wind. The findings reveal major ...
Oct. 29, 2026 Mathematicians have uncovered what they argue is a fundamental flaw in the standard model of the universe, potentially challenging the need for dark energy. Their calculations suggest that the ...
Oct. 28, 2026 Scientists have uncovered seven surprising stages that space rocks go through as they hurtle toward Earth, revealing that melting and violent fragmentation, rather than simple evaporation, determine ...
Oct. 27, 2026 A scorching lava planet 280 light-years away has surprised astronomers by apparently maintaining a thick atmosphere despite conditions that should have stripped it away billions of years ago. James ...
Oct. 27, 2026 Scientists have created one of the largest and most detailed simulations of the early universe ever made, offering an extraordinary new glimpse into ...
Oct. 26, 2026 A solar eclipse recorded more than 2,700 years ago is revealing surprising secrets about Earth's rotation and the Sun's ancient behavior. By ...
Oct. 25, 2026 Astronomers have discovered three actively feeding black holes inside a single galaxy more than 12.5 billion light-years away, revealing a remarkable scene from the universe’s infancy. Two of the ...
Oct. 24, 2026 Astronomers have uncovered evidence of a bizarre, potentially historic discovery: the first moon ever detected beyond our Solar System. Unlike familiar moons, this mysterious object is at least as ...
Oct. 24, 2026 Tiny samples from asteroid Bennu are rewriting scientists' understanding of how our Solar System formed. New evidence suggests that Bennu was born where material from the inner and outer Solar System ...
Oct. 24, 2026 The Sun’s seemingly peaceful regions are hiding a surprisingly complex magnetic world. Using a balloon-borne telescope high above Earth, scientists discovered delicate, thread-like magnetic ...