15 小时之前 · The asteroid 2024 YR4 is now rated at Level 3 out of 10 on the Torino Impact Hazard Scale, which is "a close encounter" that warrants attention from astronomers and the …

An asteroid is a minor planet —an object larger than a meteoroid that is neither a planet nor an identified comet —that orbits within the inner Solar System or is co-orbital with Jupiter (Trojan …

3 天之前 · Asteroid 99942 Apophis, about 1,200 feet (370 meters) wide, is classified as a “city killer” due to its size, which surpasses 90% of known asteroids. Initially considered a potential …

2025年1月17日 · Asteroids, sometimes called minor planets, are rocky, airless remnants left over from the early formation of our solar system about 4.6 billion years ago. Most asteroids can be …

2024年11月3日 · Asteroids, sometimes called minor planets, are rocky remnants left over from the formation of our solar system about 4.6 billion years ago. Most asteroids can be found orbiting …

Explore the 3D world of Asteroids, Comets and NEOs. Learn about past and future missions, tracking and predicting orbits, and close approaches to Earth.

2025年1月21日 · Asteroid, any of a host of small bodies, about 1,000 km (600 miles) or less in diameter, that orbit the Sun primarily between the orbits of Mars and Jupiter in a nearly flat ring …

2014年3月31日 · About once a year, an automobile-sized asteroid hits Earth’s atmosphere, creates an impressive fireball, and burns up before reaching the surface. Every 2,000 years or …

Asteroids, sometimes called minor planets, are rocky remnants left over from the early formation of our solar system about 4.6 billion years ago. The current known asteroid count is: . Most of …

2025年1月14日 · Asteroids are small, rocky objects that orbit the sun. Although asteroids orbit the sun like planets, they are much smaller than planets. A close-up image of the asteroid Ida …