NASA gives go-ahead for design of its first asteroid deflector spacecraft

3 Jul 2017

DART could prevent situations like this one occurring. Image: Vadim Sadovski/Shutterstock

As the world marked Asteroid Day, NASA revealed its latest weapon, which could one day save humanity from annihilation.

While many of the immediate fears of scientists are wrapped up in the effects of climate change on our planet, events such as Asteroid Day (30 June) highlight worries that a giant piece of space debris could one day collide with Earth, ending human civilisation as we know it.

Aside from tracking such objects to know more about them, little has been done to figure out how exactly we might be able to stop such an incident, with Hollywood films such as Armageddon not exactly providing the most scientific of answers.

Future Human

However, that could all be about to change, as NASA revealed that its first asteroid deflector is moving out of the concept phase and into preliminary design.

The Double Asteroid Redirection Test (DART) is designed to collide with an asteroid to shift its orbit  – otherwise known as the kinetic impactor technique – and we already have a target for the first test: Didymos.

Set to approach Earth in October 2022 and again in 2024, Didymos – Greek for ‘twin’ – consists of two bodies, including the 780-metre Didymos A, and the smaller orbiting asteroid Didymos B, at just 160 metres in size.

By comparison, the Chelyabinsk meteorite that exploded over Russia in 2013, causing much property damage and numerous injuries, was believed to be approximately 18 metres in size.

A perfect natural laboratory

NASA said its plan is to fire DART at Didymos B as it is an unknown quantity when it comes to composition, but its size is typical of asteroids that could potentially cause serious damage on impact.

“A binary asteroid is the perfect natural laboratory for this test,” said Tom Statler, programme scientist for DART at NASA.

“The fact that Didymos B is in orbit around Didymos A makes it easier to see the results of the impact, and ensures that the experiment doesn’t change the orbit of the pair around the sun.”

To actually target Didymos B, DART will use an on-board autonomous targeting system before striking it at a speed about nine times faster than a bullet, approximately 6km per second.

Because the craft will be destroyed, astronomers will be able to measure the effects terrestrially and see if it has what it takes to one day potentially save life on Earth.

Colm Gorey was a senior journalist with Silicon Republic