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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 8, 2025
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 ...
Oct. 25, 2025 — A UCLA-led team has achieved the sharpest-ever view of a distant star’s disk using a groundbreaking photonic lantern device on a single telescope—no multi-telescope array required. This technology splits incoming starlight into multiple ...
Oct. 25, 2025 — Researchers propose that hydrogen gas from the early Universe emitted detectable radio waves influenced by dark matter. Studying these signals, especially from the Moon’s radio-quiet environment, could reveal how dark matter clumped together ...
Oct. 15, 2025 — 3I/ATLAS, a mysterious interstellar object racing toward the Sun, is baffling scientists with its speed and origin. Some researchers suggest it could even be alien-made, drawing comparisons to probes ...
Oct. 14, 2025 — High above the Sun’s blazing equator lie its mysterious poles, the birthplace of fast solar winds and the heart of its magnetic heartbeat. For decades, scientists have struggled to see these regions, hidden from Earth’s orbit. With the upcoming ...
Oct. 12, 2025 — A colossal northern asteroid impact billions of years ago likely shaped the Moon’s south polar region and explains its uneven terrain. Researchers found that the South Pole-Aitken Basin formed from a glancing northern strike, revealing deep ...
Oct. 12, 2025 — ESA’s Mars orbiters have observed comet 3I/ATLAS, only the third interstellar comet ever discovered. The faint, distant object revealed a glowing coma as it was heated by the Sun. Researchers are still studying the data to understand its makeup ...
Oct. 9, 2025 — Mars may look calm, but new research reveals it’s a world of fierce winds and swirling dust devils racing at hurricane-like speeds. Using deep learning on thousands of satellite images from European orbiters, scientists have discovered that ...
Oct. 6, 2025 — ESA has inaugurated a powerful new 35-meter deep space antenna at its New Norcia site in Western Australia, marking a major boost to Europe’s ability to communicate with spacecraft exploring the ...
Latest Headlines
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Nov. 8, 2025 — Researchers are using black hole shadows to challenge Einstein’s theory of relativity. With new simulations and future ultra-sharp telescope images, they may uncover signs that his famous equations ...
Nov. 7, 2025 — A colossal black hole 10 billion light-years away has been caught devouring one of the universe’s biggest stars, unleashing a flare 30 times brighter than any seen before. The flare, detected by ...
Nov. 7, 2025 — Using CERN’s Super Proton Synchrotron, researchers generated plasma fireballs to simulate blazar jets. The beams stayed stable, suggesting plasma ...
Nov. 6, 2025 — A new theory claims dark matter and dark energy don’t exist — they’re just side effects of the universe’s changing forces. By rethinking gravity and cosmic timelines, it could rewrite our ...
Nov. 6, 2025 — A team of astrophysicists has unveiled how colossal stars thousands of times more massive than the Sun shaped the earliest star clusters and galaxies. These short-lived giants not only forged the ...
Nov. 6, 2025 — Evidence now suggests the universe’s expansion has started to slow, not speed up. The findings imply dark energy is weakening, marking a possible revolution in ...
Nov. 6, 2025 — Astronomers have discovered that aging stars may be devouring their closest giant planets as they swell into red giants. Using NASA’s TESS telescope to study nearly half a million stars, scientists ...
Nov. 5, 2025 — Researchers using new simulations suggest that the Milky Way’s past collisions may have reshaped its dark matter core. This distorted structure could naturally explain the puzzling gamma-ray glow ...
Nov. 4, 2025 — Astronomers are rethinking one of cosmology’s biggest mysteries: dark energy. New findings show that evolving dark energy models, tied to ultra-light axion particles, may better fit the ...
Nov. 3, 2025 — Astronomers observed a massive, multi-temperature plasma eruption from a young Sun-like star, revealing how early solar explosions could shape planets. These fierce events may have influenced the ...