Asteroid 2025 OS passed Earth this weekend
Astronomers detected an asteroid passing close to Earth on July 19, 2025. The discovery was made using a 20″ (0.5 meter) telescope at the Asteroid Terrestrial-impact Last Alert System (ATLAS) station in Chile.
Astronomers say the asteroid was traveling at a speed of 28,409 miles per hour (45,720 km/h), or 7.9 miles per second (12.70 km/sec), relative to Earth.
After analyzing the space rock trajectory, scientists realized the asteroid was closest to Earth a few hours earlier, at around 11:20 pm ET on Friday 18, 2025. At closest approach, it passed 2,534 miles (4,078 km) from Earth. That’s extremely close, considering Earth’s diameter is about 7,926 miles (12,760 kilometers).
It was designated as asteroid 2025 OS by the Minor Planet Center.
At closest approach
According to NASA/JPL, the asteroid passed just southeast of Australia during its closest approach to Earth around 11:20 pm ET on Friday 18, 2025.
Fortunately, it posed no danger to Earth. Asteroid 2025 OS is a small asteroid with an estimated size between 8.85 to 19.7 ft (2.7 and 6.0 meters) in diameter.
If asteroid 2025 OS had entered our atmosphere, most of it would have disintegrated as a spectacular meteor.
Generally, small asteroids are difficult to detect. On the other hand, larger asteroids reflect more sunlight, so they are easier to detect.
Bottom line: Astronomers discovered asteroid 2025 OS on July 19, 2025. It passed closest to Earth on July 18. It is a small asteroid, so it posed no danger to Earth.
Via IAU Minor Planet Center
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