Tag: Near Earth Asteroid

Radar images of near Earth asteroid as it zipped past the Earth

9:11 am

Radar images of near Earth asteroid
Click for original. Go here for movie made from these images.

Using the Goldstone radar antenna in California, astronomers have produced a series of 41 radar images of the near Earth asteroid 2025 OW as it made a close pass of the Earth on July 28, 2025.

Those images, cropped, reduced, and sharpened to post here, are to the right.

The asteroid safely passed at about 400,000 miles (640,000 kilometers), or 1.6 times the distance from Earth to the Moon.

The asteroid was discovered on July 4, 2025, by the NASA-funded Pan-STARRS2 survey telescope on Haleakala in Maui, Hawaii. These Goldstone observations suggest that 2025 OW is about 200 feet (60 meters) wide and has an irregular shape. The observations also indicate that it is rapidly spinning, completing one rotation every 1½ to 3 minutes, making it one of the fastest-spinning near-Earth asteroids that the powerful radar system has observed. The observations resolve surface features down to 12 feet (3.75 meters) wide.

The asteroid’s fast rotation suggests it is a solid object, structurally strong, rather than a rubble pile held together loosely by gravity. It would thus be very damaging if it should ever hit the Earth.

No worries however. The refined orbital data says this asteroid will not come this close again in the foreseeable future.

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Tiny asteroid sets record for closest fly-by of Earth

9:10 am

Astronomers using the robotic Zwicky Transient Facility (ZTF) at the Palomar Observatory in California on August 16 spotted a tiny asteroid just after it had zipped past the Earth at a distance of only 1,830 miles, the closest any asteroid has ever been seen to do so without hitting the ground.

Asteroid 2020 QG is about 10 to 20 feet (3 to 6 meters) across, or roughly the size of an SUV, so it was not big enough to do any damage even if it had been pointed at Earth; instead, it would have burned up in our planet’s atmosphere.

“The asteroid flew close enough to Earth that Earth’s gravity significantly changed its orbit,” says ZTF co-investigator Tom Prince, the Ira S. Bowen Professor of Physics at Caltech and a senior research scientist at JPL, which Caltech manages for NASA. Asteroids of this size that fly roughly as close to Earth as 2020 QG do occur about once a year or less, but many of them are never detected.

The ability to spot these things is continuing to improve, though it does not appear they have yet obtained enough information to predict 2020 QG’s full orbit, or when or if it will return.

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