Reference Terms
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Sunspot
A sunspot is a region on the Sun's surface (photosphere) that is marked by a lower temperature than its surroundings and intense magnetic activity, which inhibits convection, forming areas of low surface temperature. Although they are blindingly bright at temperatures of roughly 4000-4500 K, the contrast with the surrounding material at some 5700 K leaves them clearly visible as dark spots. If they were isolated from the surrounding photosphere they would be brighter than an electric arc. Sunspot numbers have been recorded since 1700 AD and estimated back to 11,000 BP. The recent trend is upward from 1900 to the 1960s, then somewhat downward. The Sun was last similarly active over 8,000 years ago.
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Space & Time News
May 9, 2026
May 6, 2026 A bold step toward returning humans to the Moon is underway with Blue Origin’s uncrewed MK1 “Endurance” lander, designed to test the technologies that future astronauts will rely on. Built in ...
May 6, 2026 A powerful new electromagnetic thruster has taken a major step forward after a successful high-energy test at NASA’s Jet Propulsion Laboratory. Fueled by lithium vapor and driven by intense magnetic forces, the experimental engine reached ...
May 4, 2026 Artemis II proved NASA’s deep space systems are ready for the next leap. Orion survived its high-speed return with improved heat shield performance and pinpoint landing accuracy, while the SLS rocket nailed its trajectory. Even the launch pad ...
May 4, 2026 Voyager 1 just powered down a nearly 50-year-old instrument to stay alive in deep space. The spacecraft is running critically low on energy, forcing NASA to make careful sacrifices to keep its mission going. Despite the shutdown, it continues to ...
May 3, 2026 Astronomers have unleashed a powerful new AI tool called RAVEN to comb through data from NASA’s TESS mission—and it’s paying off in a big way. By analyzing millions of stars, the system has ...
Apr. 27, 2026 A group of undergraduate students pulled off something remarkable: they built their own dark matter detector and used it to probe one of physics’ biggest mysteries. Working with limited resources but plenty of creativity, they designed a ...
Apr. 12, 2026 A major international effort has produced an ultra-precise measurement of the Universe’s expansion rate, confirming it’s faster than early-Universe models predict. By linking multiple distance-measuring techniques, scientists ruled out simple ...
Apr. 10, 2026 Scientists have proposed a surprising new way to detect gravitational waves—by observing how they change the light emitted by atoms. These waves can subtly shift photon frequencies in different directions, leaving behind a detectable signature. ...
Apr. 9, 2026 Earth’s nights are steadily getting brighter overall, but the changes vary dramatically by region. Rapid urban growth is lighting up countries like China and India, while parts of Europe are dimming due to energy-saving efforts and new lighting ...
Apr. 8, 2026 Planetary exploration may be about to get a major speed boost. Researchers tested a semi-autonomous robot that can move from rock to rock, analyzing each without waiting for human instructions. The system completed missions up to three times faster ...
Apr. 3, 2026 A new concept suggests SpaceX’s Starship could revolutionize a future mission to Uranus, one of the solar system’s most overlooked planets. By refueling in orbit and helping slow the spacecraft on arrival, it could cut travel time nearly in ...
Mar. 20, 2026 A mysterious spike of platinum buried deep in Greenland’s ice has long fueled theories of a catastrophic comet or asteroid strike 12,800 years ago—possibly triggering a sudden return to icy conditions known as the Younger Dryas. But new research ...
Latest Headlines
updated 12:56 pm ET
May 8, 2026 Scientists may have uncovered a surprising secret behind why life exists at all. A new study suggests that the Universe’s fundamental constants — ...
May 8, 2026 A mysterious comet from beyond our solar system is giving astronomers a rare glimpse into alien worlds — and it may have formed in a place far ...
May 8, 2026 The Universe’s biggest black holes may not be born giants after all. Scientists analyzing gravitational-wave signals from dozens of black hole collisions found evidence that the heaviest black ...
May 7, 2026 Astronomers using the James Webb Space Telescope have spotted something that shouldn’t exist—at least not so early in the universe. A massive galaxy, formed less than 2 billion years after the ...
May 7, 2026 A bizarre planetary pairing 190 light-years away is challenging everything astronomers thought they knew about how worlds form. A “lonely” hot Jupiter — typically found without nearby ...
May 5, 2026 A scorching, airless world just 48 light-years away is offering scientists a rare glimpse into the geology of distant planets. Using the James Webb ...
May 5, 2026 Astronomers have spotted something surprising in the far outer Solar System—a faint, short-lived atmosphere clinging to a tiny icy world that shouldn’t be able to hold one at all. The object, ...
May 3, 2026 Physicists are rethinking one of quantum mechanics’ biggest puzzles: how fuzzy possibilities become definite reality. New research suggests that spontaneous “collapse” processes—possibly ...
May 1, 2026 A decades-old cosmic mystery has finally been cracked: the strange X-rays coming from the bright star gamma-Cas are caused by a hidden stellar companion feeding off it. Using cutting-edge ...
Apr. 29, 2026 A spectacular cosmic event nicknamed “SN Winny” could help solve one of astronomy’s biggest mysteries: how fast the universe is expanding. This ...