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Near-Earth object
Near-Earth objects (NEO) are asteroids, comets and large meteoroids whose orbit intersects Earth's orbit and which may therefore pose a collision danger. Due to their size and proximity, NEOs are also more easily accessible for spacecraft from Earth and are important for future scientific investigation and commercial development. In fact, some near-Earth asteroids can be reached with a much smaller change in velocity than the Moon.
In the United States, NASA has a congressional mandate to catalogue all NEOs that are at least 1 kilometer (0.6 miles) wide. At this size and larger, an impacting NEO would cause catastrophic local damage and significant to severe global consequences. Approximately 800 of these NEOs have been detected. According to the most widely accepted estimates, there are still 200 more that have not been found yet. The United States, European Union and other nations are currently scanning for NEOs in an effort called Spaceguard. Currently efforts are under way to use an existing telescope in Australia to cover the approximately 30 percent of the sky that is not currently surveyed.
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Space & Time News
July 19, 2026
July 19, 2026 The asteroid that wiped out the dinosaurs was likely an exceptionally rare CO chondrite from a distant region of the solar system. Its unusual chemistry suggests that planet-cooling dust and debris, ...
July 18, 2026 A catastrophic asteroid breakup may have triggered a huge wave of impacts across the inner solar system about 800 million years ago. The debris was launched from near a gravitational gateway controlled by Jupiter, sending fragments toward Earth, the ...
July 17, 2026 Scientists say new technologies have reopened the debate over whether Mars could someday be terraformed, turning a once impossible idea into a serious research topic. Before anyone tries to reshape the Red Planet, though, researchers say we must ...
July 15, 2026 NASA's PACE satellite captured the Black Sea glowing turquoise during its annual phytoplankton bloom. The vivid color comes from massive numbers of coccolithophores, microscopic organisms whose reflective shells brighten the water enough to be seen ...
July 15, 2026 NASA has chosen 41 commercial technology projects that could solve critical challenges for future missions to the Moon and Mars. From powering lunar outposts to protecting spacecraft from Moon dust, the innovations are designed to push both space ...
July 14, 2026 K2-18b is one of the most promising worlds for the search for extraterrestrial life, so astronomers conducted an unusually powerful radio survey using both the VLA and MeerKAT telescopes. Advanced ...
July 14, 2026 NASA's Perseverance rover has reached an impressive new milestone on Mars, completing the equivalent of a full marathon by driving 26.2 miles (42.195 kilometers) across the Red Planet. It accomplished the feat in just five years and four months, ...
July 14, 2026 NASA is ramping up its lunar ambitions by awarding nearly $600 million for four commercial Moon landings planned for late 2028. Each mission will carry the same trio of science instruments to improve lunar navigation, study dangerous dust kicked up ...
July 12, 2026 Researchers have recreated the physics of extracting energy from a spinning black hole using a stationary device that produces synthetic ultrafast rotation. The achievement transforms a long-standing theoretical idea into a practical experiment and ...
July 10, 2026 A detailed independent study found that SpaceX's Starship is every bit as revolutionary as expected, while revealing both its impressive capabilities and its biggest remaining hurdles. It also introduces an ambitious European rocket concept that ...
July 10, 2026 Scientists have identified new clues that could help astronomers spot one of the most famous hypothetical alien megastructures: a Dyson sphere. The study finds that red dwarfs and white dwarfs are the most promising stars to examine, since advanced ...
July 8, 2026 Researchers have created an AI-based simulation that makes it much faster to model how neutron star mergers produce many of the universe's heaviest elements. The new tool could improve predictions of these powerful explosions while helping ...
Latest Headlines
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July 19, 2026 Researchers have created cosmic dust from scratch by recreating space-like conditions inside glass tubes. The dust contains complex carbon-rich molecules built from elements essential to life and ...
July 17, 2026 JWST has captured unusually detailed images of gas feeding the supermassive black hole at the center of NGC 4696. A vast filament appears to funnel material into an 800-light-year-wide spinning disk, ...
July 16, 2026 A distant Sun-like star appears to have devoured one of its planets, leaving behind a surprising chemical fingerprint. Researchers found an unusually high concentration of lithium, a strong sign that ...
July 15, 2026 NASA's James Webb Space Telescope has revealed new details about the blistering lava planet 55 Cancri e, where temperatures are high enough to melt ...
July 15, 2026 Four nearby white dwarf stars have been discovered hiding in plain sight beside brighter red dwarf companions. Hubble's ultraviolet observations finally revealed the long-hidden stellar remnants, ...
July 13, 2026 Dark matter may be far more complicated than scientists once believed. A new study suggests it could consist of at least two different kinds of particles that slowly separate over time, with heavier ...
July 13, 2026 Scientists have developed a new framework that could finally apply the laws of thermodynamics to real, ever-changing black holes instead of only perfectly stable ones. The advance may improve our ...
July 12, 2026 A new study suggests spacecraft exhaust could quickly contaminate the moon's most scientifically valuable regions, potentially masking ancient clues about how life began on Earth. Researchers say ...
July 9, 2026 What if time doesn't actually exist until something changes? Scientists at the University of Birmingham created a tiny "mini universe" using 24,000 ultracold atoms and showed that the flow of time ...
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