Tonight, a Japanese spacecraft completed a touchdown on the surface of an asteroid, where it fired a projectile at the rock’s surface rock. A successful mission could help advance understanding of how our planet formed in the early solar system.

Since last year, Hayabusa2, the Japanese probe, has been studying the asteroid called Ryugu. It surveyed the object’s surface, and in the following months landed multiple robotic probes on its rocky terrain. All that work was done to support the aim of Thursday’s operation (Friday in Japan) where it attempted to collect samples from Ryugu’s surface and later bring them home to Earth. Other attempts could be made in the near future.

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What did Hayabusa2 do when it landed?

Hayabusa2 tried to collect material from the rugged surface of the asteroid with a device called a sampler horn.

To make small enough fragments, the spacecraft fired a projectile made of the metal tantalum — basically a bullet — at the asteroid’s surface. Earlier this month, the mission’s managers reported their simulation of this procedure on Earth to demonstrate that it would be able to succeed.