"Close Call: Massive 'Potentially Hazardous' Asteroid Safely Passes Earth"
A "potentially hazardous" 2,000-foot-wide asteroid, 2013 NK4, has made its closest approach to Earth, but poses no threat. It will be visible via amateur telescopes until April 17. Despite its classification, it is not expected to impact Earth. Astronomers are tracking it with radio telescopes to capture specialized radar images. The asteroid orbits the sun every 378 days and will return for another flyby in 2025. This is the closest approach in at least 125 years, and it won't be visible again for over 30 years.