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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
October 27, 2025
Oct. 27, 2025 — Two Sydney PhD students have pulled off a remarkable space science feat from Earth—using AI-driven software to correct image blurring in NASA’s James Webb Space Telescope. Their innovation, called AMIGO, fixed distortions in the telescope’s ...
Oct. 25, 2025 — A UCLA-led team has achieved the sharpest-ever view of a distant star’s disk using a groundbreaking photonic lantern device on a single telescope—no multi-telescope array required. This technology splits incoming starlight into multiple ...
Oct. 25, 2025 — Researchers propose that hydrogen gas from the early Universe emitted detectable radio waves influenced by dark matter. Studying these signals, especially from the Moon’s radio-quiet environment, could reveal how dark matter clumped together ...
Oct. 15, 2025 — 3I/ATLAS, a mysterious interstellar object racing toward the Sun, is baffling scientists with its speed and origin. Some researchers suggest it could even be alien-made, drawing comparisons to probes ...
Oct. 14, 2025 — High above the Sun’s blazing equator lie its mysterious poles, the birthplace of fast solar winds and the heart of its magnetic heartbeat. For decades, scientists have struggled to see these regions, hidden from Earth’s orbit. With the upcoming ...
Oct. 12, 2025 — A colossal northern asteroid impact billions of years ago likely shaped the Moon’s south polar region and explains its uneven terrain. Researchers found that the South Pole-Aitken Basin formed from a glancing northern strike, revealing deep ...
Oct. 12, 2025 — ESA’s Mars orbiters have observed comet 3I/ATLAS, only the third interstellar comet ever discovered. The faint, distant object revealed a glowing coma as it was heated by the Sun. Researchers are still studying the data to understand its makeup ...
Oct. 9, 2025 — Mars may look calm, but new research reveals it’s a world of fierce winds and swirling dust devils racing at hurricane-like speeds. Using deep learning on thousands of satellite images from European orbiters, scientists have discovered that ...
Oct. 6, 2025 — ESA has inaugurated a powerful new 35-meter deep space antenna at its New Norcia site in Western Australia, marking a major boost to Europe’s ability to communicate with spacecraft exploring the ...
Oct. 3, 2025 — Researchers have designed a new type of gravitational wave detector that operates in the milli-Hertz range, a region untouched by current observatories. Built with optical resonators and atomic clocks, the compact detectors can fit on a lab table ...
Sep. 30, 2025 — A new boron-rich compound, manganese diboride, delivers much higher energy density than current solid-rocket materials while remaining stable until intentionally ignited. Its power comes from an unusual, strained atomic structure formed during ...
Sep. 18, 2025 — Astronomers have long relied on supercomputers to simulate the immense structure of the Universe, but a new tool called Effort.jl is changing that. By mimicking the behavior of complex cosmological models, this emulator delivers results with the ...
Latest Headlines
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Oct. 27, 2025 — Researchers have directly observed torsional Alfvén waves twisting through the Sun’s corona — magnetic waves first predicted over 80 years ago. Captured using the Daniel K. Inouye Solar ...
Oct. 27, 2025 — A massive crater hidden beneath the Atlantic seafloor has been confirmed as the result of an asteroid strike from 66 million years ago. The new 3D ...
Oct. 23, 2025 — Researchers suggest that dark matter might subtly color light red or blue as it passes through, revealing traces of its existence. Using a network-like model of particle connections, they argue that ...
Oct. 22, 2025 — Our Milky Way is far from calm — it ripples with a colossal wave spanning tens of thousands of light-years, revealed by ESA’s Gaia telescope. ...
Oct. 19, 2025 — Researchers from The University of Western Australia node at the International Centre for Radio Astronomy Research (ICRAR) have uncovered a colossal bridge of neutral hydrogen gas linking two dwarf ...
Oct. 19, 2025 — Mars’ north polar vortex locks its atmosphere in extreme cold and darkness, freezing out water vapor and triggering a dramatic rise in ozone. Scientists found that the lack of sunlight and moisture ...
Oct. 18, 2025 — Scientists at Johns Hopkins may be closing in on dark matter’s elusive trail, uncovering a mysterious gamma ray glow at the heart of our galaxy that could signal unseen matter colliding — or ...
Oct. 18, 2025 — Researchers have unveiled a new model for the universe’s birth that replaces cosmic inflation with gravitational waves as the driving force behind creation. Their simulations show that gravity and ...
Oct. 17, 2025 — Researchers have discovered chemical fingerprints of Earth's earliest incarnation, preserved in ancient mantle rocks. A unique imbalance in potassium isotopes points to remnants of “proto Earth” ...
Oct. 17, 2025 — Scientists from NASA and Chalmers University have discovered that incompatible substances can mix on Titan’s icy surface, breaking the “like dissolves like” rule of chemistry. Under ultra-cold ...