New Delhi, March 9 -- An asteroid that NASA used for target practice a few years ago was nudged into a slightly different route around the sun, findings that could help divert a future incoming killer space rock, scientists reported Friday.

It's the first time that a celestial body's orbit around the sun was deliberately changed. The asteroid that NASA's Dart spacecraft slammed into was never a threat to Earth.

"This study marks a notable step forward in our ability to prevent future asteroid impacts on Earth," the international research team wrote in Science Advances.

The changes were slight - reductions of just one-tenth of a second and one-half of a mile (720 meters) to a solar lap spanning two years and hundreds of millions of mile...