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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
August 13, 2025
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June 2, 2025 — Researchers have engineered a laser device smaller than a penny that they say could power everything from the LiDAR systems used in self-driving vehicles to gravitational wave detection, one of the most delicate experiments in existence to observe ...
Latest Headlines
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Aug. 13, 2025 — A groundbreaking quantum device small enough to fit in your hand could one day answer one of the biggest questions in science — whether the ...
Aug. 13, 2025 — Mars, once thought too cold and dry for liquid water, may briefly host salty brines twice a day during certain seasons. These fleeting bursts wouldn’t be enough to sustain humans, but they could ...
Aug. 13, 2025 — Astronomers have finally confirmed the existence of a long-suspected companion star orbiting Betelgeuse, the iconic red supergiant in Orion. Using the advanced 'Alopeke speckle imager on the Gemini ...
Aug. 13, 2025 — For decades, scientists puzzled over why Uranus seemed colder than expected. Now, an international research team led by the University of Houston has solved the mystery: Uranus emits more heat than ...
Aug. 13, 2025 — UC Santa Cruz physicist Stefano Profumo has put forward two imaginative but scientifically grounded theories that may help solve one of the biggest mysteries in physics: the origin of dark matter. In ...
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Aug. 11, 2025 — NASA’s Lunar Trailblazer, a mission designed to create high-resolution maps of water on the Moon, ended after losing contact with the spacecraft just one day after its February 26 launch. Despite ...
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