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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
August 4, 2026
July 31, 2026 Scientists have built the first all-optical photonic time crystal, allowing them to reshape the behavior of terahertz light at extraordinary speeds. The breakthrough could open the door to ultrafast computing, smarter communication systems, advanced ...
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July 23, 2026 NASA is preparing for future astronaut landings on the Moon with an unusually ambitious orbital rehearsal. During Artemis III in 2027, Orion astronauts will rendezvous and dock separately with ...
July 21, 2026 China’s Chang’e-6 samples have uncovered a surprising difference between the Moon’s two hemispheres. Solar wind particles penetrated deeper into the far-side soil because Earth’s ...
July 19, 2026 The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system. Its unusual chemistry suggests that planet-cooling dust and debris, ...
July 18, 2026 A catastrophic asteroid breakup may have triggered a huge wave of impacts across the inner solar system about 800 million years ago. The debris was launched from near a gravitational gateway controlled by Jupiter, sending fragments toward Earth, the ...
July 17, 2026 Scientists say new technologies have reopened the debate over whether Mars could someday be terraformed, turning a once impossible idea into a serious research topic. Before anyone tries to reshape the Red Planet, though, researchers say we must ...
July 15, 2026 NASA's PACE satellite captured the Black Sea glowing turquoise during its annual phytoplankton bloom. The vivid color comes from massive numbers of coccolithophores, microscopic organisms whose reflective shells brighten the water enough to be seen ...
July 15, 2026 NASA has chosen 41 commercial technology projects that could solve critical challenges for future missions to the Moon and Mars. From powering lunar outposts to protecting spacecraft from Moon dust, the innovations are designed to push both space ...
July 14, 2026 K2-18b is one of the most promising worlds for the search for extraterrestrial life, so astronomers conducted an unusually powerful radio survey using both the VLA and MeerKAT telescopes. Advanced ...
July 14, 2026 NASA's Perseverance rover has reached an impressive new milestone on Mars, completing the equivalent of a full marathon by driving 26.2 miles (42.195 kilometers) across the Red Planet. It accomplished the feat in just five years and four months, ...
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Aug. 2, 2026 Dark matter particles may exert a hidden force on one another, but its effects are stranger than expected. An extra attraction helps the particles cluster, yet it also makes dark matter effectively ...
Aug. 1, 2026 Scientists have identified LHAASO J1912+1014u as a cosmic accelerator that can push protons beyond one quadrillion electron volts. The finding may ...
Aug. 1, 2026 NASA’s Curiosity rover has entered a Martian valley covered by an astonishing “sea” of tiny polygon-shaped fractures. The honeycomb patterns, each only a few inches wide, stretch across the ...
Aug. 1, 2026 Primordial black holes may occasionally pass through white dwarf stars and trigger enormous Type Ia supernova explosions. Researchers found that these events could explain chemical patterns seen in ...
July 31, 2026 A black hole observed during a dramatic 2023 eruption did not simply devour gas from its nearby companion star. It also expelled large amounts of material through powerful jets and winds, even after ...
July 31, 2026 Scientists traced a mysterious surge of low-energy gamma rays from zinc-70 to magnetic changes occurring inside its nucleus. The breakthrough could improve models of how stars, supernovae, and ...
July 29, 2026 Europa’s hidden ocean has made the icy moon one of the solar system’s most promising places to search for habitable conditions. Scientists have hoped that water from this deep ocean might rise ...