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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
April 8, 2026
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 ...
Mar. 14, 2026 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 ...
Feb. 24, 2026 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 ...
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 ...
Jan. 28, 2026 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 ...
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 ...
Latest Headlines
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Apr. 8, 2026 For all its ancient, familiar features, the Moon is still changing—and sometimes in dramatic ways. Scientists recently identified a fresh 22-meter-wide crater by comparing orbital images taken ...
Apr. 8, 2026 A bizarre, record-breaking neutrino detected in 2023 may have originated from an exploding primordial black hole—a relic from the early universe. ...
Apr. 6, 2026 Earth may have won a cosmic chemistry lottery. Researchers found that during the planet’s earliest formation, oxygen had to be in an extremely narrow “Goldilocks zone” for two life-essential ...
Apr. 6, 2026 A strange “forbidden” planet spotted by the James Webb Space Telescope is turning planetary science on its head. TOI-5205 b, a Jupiter-sized world orbiting a small, cool star, has an atmosphere ...
Apr. 6, 2026 Scientists have taken a major step toward probing one of physics’ biggest mysteries—how gravity and quantum mechanics fit together—by creating the first unified way to detect tiny “ripples” ...
Apr. 5, 2026 Mars may look like a quiet, dusty world, but it’s actually buzzing with hidden electrical activity. Powerful dust storms and swirling dust devils ...
Apr. 4, 2026 Dying stars may be wiping out nearby giant planets as they expand into red giants. Astronomers found that these close-in planets become increasingly rare around more evolved stars, suggesting many ...
Apr. 4, 2026 A group of undergraduate students stumbled into a cosmic time capsule—one of the oldest stars ever discovered—while combing through massive ...
Apr. 4, 2026 Asteroid impacts may have helped kick-start life on Earth by creating hot, chemical-rich environments ideal for early biology. These impact-generated hydrothermal systems could have lasted thousands ...
Apr. 3, 2026 Saturn’s magnetic field isn’t the smooth, symmetrical shield scientists see around Earth. Instead, it’s noticeably skewed, and researchers now think they understand why. By analyzing years of ...