A brilliant X-ray source is not automatically a black hole. Matter falling toward a neutron star can also become intensely luminous, and some neutron stars have surprised astronomers by producing far more radiation than expected. Identifying the object requires evidence about its mass, its rotation and whether incoming gas encounters a material surface. The distinction […]

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Venus can reach its greatest brilliance while a telescope shows only a crescent. A nearly full Venus exposes more of its sunlit hemisphere, yet that does not necessarily deliver more light to Earth. The missing part of the explanation is distance: a closer crescent can look much larger than a distant, almost fully illuminated disk. […]

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Saturn’s south pole has a ten-sided atmospheric wave, giving astronomers a new counterpart to the planet’s famous northern hexagon. The southern pattern appears to be evolving, raising a question that a single striking image cannot answer: will it become another enduring feature of the planet’s weather? A study announced on September 2 traces the feature […]

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Twenty-seven faint objects beyond Neptune have emerged from a deep James Webb Space Telescope survey, extending the search for the solar system’s building blocks to worlds only kilometres across. Hubble observations of part of the sample add a second clue: their colors resemble those of larger objects, suggesting that size alone has not erased the […]

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Dark energy is one of the least satisfying names in astronomy because it sounds more specific than it is. Scientists did not discover a glowing substance called dark energy. They gave that name to the unknown influence associated with the accelerating expansion of the universe. The evidence is strong that the expansion is speeding up […]

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In empty space, light travels at exactly 299,792,458 meters per second. That is about 300,000 kilometers per second, or 186,282 miles per second. It is the fastest speed at which matter, energy, or information can travel through the universe. The number is so large that it is easy to treat light as instantaneous. Across cosmic […]

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Satellite constellations can leave bright trails across telescope images. Here is what that means for astronomy and the night sky.

The post Satellites Are Changing the Night Sky. What Astronomers Can Still See appeared first on Curiosmos.

A neutron star is what remains after the core of a massive star collapses. It is not a small ordinary star. It is the crushed core of a dead one, compressed until protons and electrons are forced together and most of the material becomes neutrons. The result is one of the strangest objects in the […]

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