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Nasa say Dart spacecraft successfully changed path of asteroid

Debris from Dimorphos asteroidNASA/ESA/STScI/Hubble

A trail of debris after the Dart probe collision with the asteroid

American space agency Nasa has said its attempt to change the path of an asteroid was successful.

The Dart spacecraft crashed into the Dimorphos asteroid at the end of September, 10 months after it was launched as part of an experiment to try to change the space rock's direction.

This asteroid wasn't on a path to hit Earth, the experiment was to learn whether it was possible to change the course of an asteroid in case it is needed in the future.

Nasa's Bill Nelson said: "This mission shows that Nasa is trying to be ready for whatever the Universe throws at us,"

"I believe that Nasa has proven that we are serious as a defender of the planet,".

What is an asteroid?

  • An asteroid is a small rocky object that orbits the Sun

  • These become meteors when they burn up in the Earth's atmosphere

  • They come in lots of different sizes. Vesta is one of the biggest at 530km (330 miles) in diameter - that's bigger than the distance from London to Paris!

After Dart made impact with the asteroid, Nasa researchers monitored its direction using telescopes on earth and in space.

The space agency released this data on Tuesday, including new pictures from the Hubble Space Telescope.

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Dart, which stands for Double Asteroid Redirection Test, is only around the size of a fridge but by crashing directly into Dimorphos it was measured to have changed its path by "tens of metres".

Last week scientists also learned that the asteroid had left an absolutely huge trail of debris, after impact with Dart.

"Dart just gave it a small nudge," said Dr Nancy Chabot who was involved in the mission, "But if you wanted to do this in the future, you'd want to do it years in advance"

"Warning time is really key here in order to enable this sort of asteroid deflection to be used in the future as part of a much larger planetary defence strategy."

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