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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

March 21, 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 ...
Mars didn’t always look like the barren world we see today. Over billions of years, the Sun’s solar wind stripped away much of its atmosphere, helping transform it from a warmer, wetter planet ...
Scientists have proposed a surprising connection between solar flares and earthquakes. When solar activity disturbs the ionosphere, it may generate electric fields that penetrate fragile fracture zones in Earth’s crust. If a fault is already ...
NASA’s Perseverance rover has just made history by driving across Mars using routes planned by artificial intelligence instead of human operators. A vision-capable AI analyzed the same images and terrain data normally used by rover planners, ...
Hidden lava tunnels on the Moon and Mars could one day shelter human explorers, offering natural protection from radiation and space debris. A European research team has unveiled a bold new mission concept that uses three different robots working ...
Low-Earth orbit is more crowded—and fragile—than it looks. Satellites constantly weave past each other, burning fuel and making dozens of evasive maneuvers every year just to stay safe. A major solar storm could disable navigation and ...
Physicists have unveiled a new way to simulate a mysterious form of dark matter that can collide with itself but not with normal matter. This self-interacting dark matter may trigger a dramatic collapse inside dark matter halos, heating and ...
When scientists sent bacteria-infecting viruses to the International Space Station, the microbes did not behave the same way they do on Earth. In microgravity, infections still occurred, but both viruses and bacteria evolved differently over time. ...
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 ...
Nearly everything in the universe is made of mysterious dark matter and dark energy, yet we can’t see either of them directly. Scientists are developing detectors so sensitive they can spot particle interactions that might occur once in years or ...
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. ...
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 ...

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