NASA and the European Space Agency (ESA) will team up to save Earth from getting destroyed by an approaching double asteroid. The space agencies’ upcoming missions will involve visiting and deflecting the massive Didymos asteroid system and its gigantic moon.

Didymos is classified as a potentially hazardous asteroid due to the impact risk it poses on Earth. This is an asteroid system composed of a large space rock that’s about 2,500 feet long with a moon of about 540 feet wide.

Although Didymos is smaller than the kilometer-sized asteroids that can trigger a wide-scale extinction-level event on Earth, it can still cause significant damage to the planet if it hits. Because of this, both NASA and the ESA have hatched their own missions to study the asteroid system as well as to prevent it from causing a major impact event.

On NASA’s part, the space agency will launch a program known as the Double Asteroid Redirection Test (DART). As its name suggests, this mission involves deflecting an asteroid by crashing a spacecraft on it, Space.com reported.

For the main objective of DART, NASA will target the Didymos moon to see if it can be deflected by a spacecraft crash. This mission will determine if the space agency’s plan to redirect asteroids away from a collision course with Earth will actually work. NASA intends to launch the DART mission sometime in 2021.

Similarly, ESA will also send a spacecraft to Didymos through an upcoming mission known as Hera. Through this mission, ESA aims to gain a deeper understanding of the trajectory of asteroids in order to prepare for future deflection operations.

According to the ESA, NASA will first carry out its DART mission on Didymos. ESA will then launch Hera to the asteroid system to study DART’s effect on the space rock.

“First, NASA will crash its DART spacecraft into the smaller asteroid – known as Didymoon – before ESA’s Hera comes in to map the resulting impact crater and measure the asteroid’s mass,” ESA said in a statement.

“Hera will carry two CubeSats on board, which will be able to fly much closer to the asteroid’s surface, carrying out crucial scientific studies, before touching down,” the agency added. “Hera’s up-close observations will turn asteroid deflection into a well-understood planetary defense technique.”

Two Very Different Asteroids Image of two different asteroids captured by NASA. Photo: NASA/JPL/JHUAPL