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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
January 15, 2026
Jan. 8, 2026 A team of physicists has discovered a surprisingly simple way to build nuclear clocks using tiny amounts of rare thorium. By electroplating thorium onto steel, they achieved the same results as years of work with delicate crystals — but far more ...
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Jan. 6, 2026 A distant pulsar’s radio signal flickers as it passes through space, much like stars twinkle in Earth’s atmosphere. By monitoring this effect for 10 months, researchers watched the pattern slowly evolve as gas, Earth, and the pulsar all moved. ...
Jan. 6, 2026 Mars looks familiar from afar, but surviving there means creating a protective oasis in a hostile world. Instead of shipping construction materials from Earth, researchers are exploring how to use Martian soil as the raw ingredient. Two tough ...
Jan. 2, 2026 A physicist has proposed a bold experiment that could allow gravitational waves to be manipulated using laser light. By transferring minute amounts of energy between light and gravity, the ...
Dec. 31, 2025 As we age, our immune system quietly loses its edge, and scientists have uncovered a surprising reason why. A protein called platelet factor 4 naturally declines over time, allowing blood stem cells to multiply too freely and drift toward unhealthy, ...
Dec. 25, 2025 Scientists are digging into the hidden makeup of carbon-rich asteroids to see whether they could one day fuel space exploration—or even be mined for valuable resources. By analyzing rare meteorites ...
Dec. 22, 2025 Astronomers have uncovered a massive hidden planet and a rare “failed star” by combining ultra-precise space data with some of the sharpest ground-based images ever taken. Using the Subaru Telescope in Hawaiʻi, the OASIS survey tracked subtle ...
Dec. 19, 2025 Gravitational waves from black holes may soon reveal where dark matter is hiding. A new model shows how dark matter surrounding massive black holes leaves detectable fingerprints in the waves recorded by future space ...
Dec. 17, 2025 Researchers have shown that quantum signals can be sent from Earth up to satellites, not just down from space as previously believed. This breakthrough could make global quantum networks far more powerful, affordable, and ...
Dec. 6, 2025 SQUIRE aims to detect exotic spin-dependent interactions using quantum sensors deployed in space, where speed and environmental conditions vastly improve sensitivity. Orbiting sensors tap into ...
Dec. 3, 2025 Earth’s orbit is getting crowded with broken satellites and leftover rocket parts. Researchers say the solution is to build spacecraft that can be repaired, reused, or recycled instead of abandoned. They also want new tools to collect old debris ...
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Jan. 15, 2026 Dark matter, one of the Universe’s greatest mysteries, may have been born blazing hot instead of cold and sluggish as scientists long believed. New research shows that dark matter particles could ...
Jan. 13, 2026 Scientists have pulled back the curtain on one of the most extreme solar regions seen in decades, tracking it almost nonstop for three months as it unleashed powerful space weather. By combining ...
Jan. 13, 2026 At extreme pressures and temperatures, water becomes superionic — a solid that behaves partly like a liquid and conducts electricity. This unusual form is believed to shape the magnetic fields of ...
Jan. 12, 2026 Scientists observing the red giant star R Doradus have found that starlight isn’t strong enough to drive its stellar winds, overturning a ...
Jan. 11, 2026 The accelerating expansion of the universe is usually explained by an invisible force known as dark energy. But a new study suggests this mysterious ...
Jan. 10, 2026 Scientists have discovered an enormous stream of super-hot gas erupting from a nearby galaxy, driven by a powerful black hole at its center. The jets ...
Jan. 10, 2026 Crystals hidden in Australia’s oldest rocks have revealed new clues about how Earth and the Moon formed. The study suggests Earth’s continents didn’t begin growing until hundreds of millions of ...
Jan. 10, 2026 Astronomers have uncovered the long-hidden cause behind Betelgeuse’s strange behavior: a small companion star carving a visible wake through the giant’s vast atmosphere. Using nearly eight years ...
Jan. 9, 2026 Hubble has revealed a strange cosmic object called Cloud-9, a dark matter–dominated cloud with no stars at all. Scientists believe it is a “failed galaxy,” a leftover building block from the ...
Jan. 8, 2026 Using NASA’s IXPE, astronomers captured an unprecedented view of a white dwarf star actively feeding on material from a companion. The data revealed giant columns of ultra-hot gas shaped by the ...