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Planetary nebula
A planetary nebula is an astronomical object consisting of a glowing shell of gas and plasma formed by certain types of stars at the end of their lives. They are in fact unrelated to planets; the name originates from a supposed similarity in appearance to giant planets. They are a short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years. About 1,500 are known to exist in the Milky Way Galaxy. Planetary nebulae are important objects in astronomy because they play a crucial role in the chemical evolution of the galaxy, returning material to the interstellar medium which has been enriched in heavy elements and other products of nucleosynthesis (such as carbon, nitrogen, oxygen and calcium). In other galaxies, planetary nebulae may be the only objects observable enough to yield useful information about chemical abundances.
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Space & Time News
February 17, 2026
Feb. 2, 2026 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, ...
Feb. 2, 2026 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 ...
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Jan. 19, 2026 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 ...
Jan. 18, 2026 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. ...
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 ...
Jan. 8, 2026 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 ...
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 ...
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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 ...
Latest Headlines
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Feb. 17, 2026 Scientists scanning the heart of the Milky Way have spotted a tantalizing signal: a possible ultra-fast pulsar spinning every 8.19 milliseconds near Sagittarius A*, the supermassive black hole at our ...
Feb. 16, 2026 New data from major dark-energy observatories suggest the universe may not expand forever after all. A Cornell physicist calculates that the cosmos is heading toward a dramatic reversal: after ...
Feb. 14, 2026 Astronomers have uncovered a distant planetary system that flips a long-standing rule of planet formation on its head. Around the small red dwarf star LHS 1903, scientists expected to find rocky ...
Feb. 14, 2026 A massive star 2.5 million light-years away simply vanished — and astronomers now know why. Instead of exploding in a supernova, it quietly ...
Feb. 13, 2026 A dazzling new Hubble image peels back the layers of the mysterious Egg Nebula, a rare and fleeting phase in a Sun-like star’s death just 1,000 ...
Feb. 12, 2026 Dust from asteroid Bennu is revealing a surprising origin story for life’s building blocks. New research suggests some amino acids formed in frozen ice exposed to radiation, not warm liquid water ...
Feb. 12, 2026 Scientists have uncovered evidence of a massive underground lava tube hidden beneath the surface of Venus, revealing a new layer of the planet’s volcanic history. By reexamining radar data from ...
Feb. 12, 2026 A newly identified planet candidate, HD 137010 b, looks strikingly Earth-like in size and orbit — but it may be colder than Mars due to its dimmer star. If it has a thick enough atmosphere, though, ...
Feb. 12, 2026 Scientists studying a rock sample collected by NASA’s Curiosity rover have uncovered something tantalizing: the largest organic molecules ever ...
Feb. 12, 2026 Deep inside a nearby galaxy cloaked in thick clouds of gas and dust, astronomers have uncovered a surprising treasure trove of organic molecules ...