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Comet

A comet is a small body in the solar system that orbits the Sun and (at least occasionally) exhibits a coma (or atmosphere) and/or a tail - both primarily from the effects of solar radiation upon the comet's nucleus, which itself is a minor body composed of rock, dust, and ices. Comets' orbits are constantly changing: their origins are in the outer solar system, and they have a propensity to be highly affected (or perturbed) by relatively close approaches to the major planets. Some are moved into sungrazing orbits that destroy the comets when they near the Sun, while others are thrown out of the solar system forever.

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Space & Time News

December 26, 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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
A UC Irvine team uncovered a never-before-seen quantum phase formed when electrons and holes pair up and spin in unison, creating a glowing, liquid-like state of matter. By blasting a custom-made material with enormous magnetic fields, the ...
A massive solar storm in May 2024 gave scientists an unprecedented look at how Earth’s protective plasma layer collapses under intense space weather. With the Arase satellite in a perfect observing position, researchers watched the plasmasphere ...
New observations show that asteroid 1998 KY26 is a mere 11 meters across and spinning twice as fast as previously thought. The discovery adds complexity to Hayabusa2’s 2031 mission but also heightens scientific interest. The asteroid’s ...
Scientists built a tiny clock from single-electron jumps to probe the true energy cost of quantum timekeeping. They discovered that reading the clock’s output requires vastly more energy than the clock uses to function. This measurement process ...
Researchers combined deep learning with high-resolution physics to create the first Milky Way model that tracks over 100 billion stars individually. Their AI learned how gas behaves after supernovae, removing one of the biggest computational ...
Dark matter may be invisible, but scientists are getting closer to understanding whether it follows the same rules as everything we can see. By comparing how galaxies move through cosmic gravity wells to the depth of those wells, researchers found ...

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