NASA spacecraft to collide with asteroid on Sept 26; here's what we know

The DART mission first launched nearly a year ago on November 24, 2021, to test the use of a kinetic impactor, in order to change the orbit of an asteroid, in the first of its kind attempt

The National Aeronautics and Space Administration (NASA's) Double Asteroid Redirection Test (DART) mission is set to clash with an asteroid on September 26. The aircraft will make history as it crashes an asteroid in the world's first planetary defence test.

The DART mission will slam a spacecraft into the tiny moon of the asteroid Didymos, with the impact set at 4:30 am on September 27 in India.

DART Mission

The mission first launched nearly a year ago, on November 24, 2021, to test the use of a kinetic impactor to change the orbit of an asteroid in the first of its kind attempt. It is reportedly the size of a school bus and has been travelling to reach its asteroid target since its launch. 

While there is no asteroid headed for Earth as of now, there might be a possibility of one in future. NASA observes these asteroids and has developed a technology which could prevent them asteroid from striking Earth. 

Where is the DART mission headed?

The DART spacecraft is heading for a double-asteroid system, where a tiny "moon" asteroid, named Dimorphos, orbits a giant asteroid, Didymos. Didymos, known as "twin" in Greek, is roughly 2,560 feet (780 meters) in diameter. Meanwhile, Dimorphos measures 525 feet (160 meters) across, and its name means "two forms."

At the time of the impact, both Didymos and Dimorphos will be relatively close to Earth, within 6.8 million miles (11 million kilometres).

What is the purpose of DART?

The DART mission, which is 100 times smaller than Dimorphos, will crash into the moon head-on. Due to its smaller size, the spacecraft will change the asteroid's speed. According to the DART mission team, the crash will be like a golf cart crashing into one of the Great Pyramids. 

Once the DART mission sets sight of Dimorphos, it will accelerate to 13,421 miles per hour (21,600 kilometres per hour) and crash into the moon head-on. 

Where to watch the DART mission?

The mission will share the view of the double-asteroid system through an instrument known as the Didymos Reconnaissance and Asteroid Camera for Optical navigation (DRACO). It is a high-resolution camera instrument that aims to catch images of the two asteroids, which will stream back to Earth at a rate of one image per second in what will appear like a video. The mission can be viewed on NASA's website, which will commence the live streaming at around 3:30 am (India time).

Who will watch the impact?

Many observers will be watching the impact, including the LICIACube, James Webb Space Telescope, the Hubble Space Telescope and NASA's Lucy mission.