NASA is launching a probe to smash into an asteroid. It's practice for pushing city-killing space rocks away from Earth.

A new space probe is about to be launched by NASA.

The Double Asteroid Redirection Test is sending a spaceship to slam into an asteroid. The asteroid it's aiming for is larger than a pebble. The space rock should be able to change its path because of the impact.

One day, NASA may be able to divert a rogue space rock headed for Earth. NASA estimates that 40% of asteroids that are 140 meters or larger have been spotted, but scientists don't currently know of any dangerous Earth-bound asteroids. An asteroid could level the city.

The Dimorphos asteroid is 160 m in diameter.

The office of the science.

Tom Statler, a NASA astrophysicist working on the mission, said DART is a two-pronged test of a planetary-defense method.

The first test is to see if we can hit the asteroid. The second test is to see if a real asteroid will respond to being hit. The first test ends and the second test starts when the spaceship is destroyed.
The asteroid's response to the impact will help NASA determine how large future probes should be.

DART is going to start at 1:20 a.m. On Wednesday, the rocket will be launched from the Space Force Base in California. It will reach its destination in September 2022.

The launch will be streamed on NASA's website at 12:30 a.m. On Wednesday. You can watch below.

NASA could save the world from an asteroid with 5 to 10 years' advance notice.

DART will speed toward the asteroids. Didymos is a moonlet called Dimorphos. DART is trying to get to the moonlet. It is much smaller than its companion.

Didymos and Dimorphos do not pose a threat to Earth. They're ideal for testing the "kinetic impactor" method, which involves crashing a spaceship into an asteroid at high speeds.

The APL is a NASA/Johns Hopkins project.

DART won't be able to see Dimorphos until an hour before impact. NASA engineers have programmed the craft to quickly calculate the asteroid's center and steer it towards that point.

The asteroid should be pushed closer to Didymos by 15,000 miles per hour (4 miles per second) if the spaceship hits Dimorphos's center. The impact will cause an explosion of between 22,000 and 220,000 pounds of rock material, which could give it an even bigger push than DART itself. Dimorphos should go at least 73 seconds faster than before.

Astronomers will be watching the asteroid's trajectory to see how it will change after the impact.
One day, the method could save Earth from an asteroid. There is a catch. Insider was told that NASA needs about five to 10 years' advanced notice of an Earth-bound asteroid to use a DART-like mission.

DART technicians inspect a solar array in August of 2021.

NASA/JohnsHopkins APL.

It takes a long time to design and build a spaceship and travel to the asteroid. The probe would need to hit an asteroid before it gets to Earth. The impact would take the rock off course at first. Over time, that change would leave it behind on Earth.

NASA is building a space telescope that will be used to identify hazardous asteroids with enough lead time. NASA hopes that the telescope will bring the asteroids catalogue up to 90 percent, since 40% of them have been identified so far.

Astronomers will be able to see if DART worked. The European Space Agency plans to launch a follow-up mission to look at Didymos and Dimorphos. Hera will look at the aftermath. It will map Dimorphos, measure its mass, and examine the crater that DART left there.