Summary:
- The Earth has a new "minimoon" - a small asteroid that has been temporarily captured by Earth's gravity and is now orbiting the planet.
- The minimoon, named 2020 CD3, is only about 6-12 feet (2-4 meters) in diameter and is not visible to the naked eye.
- Astronomers are studying the minimoon to better understand the dynamics of how objects are captured and held in orbit around the Earth.