The Rosetta space probe spent 10-year exploring the deep, dark corners of space. Just minutes ago the probe's Philae Lander successfully landed on the comet more than 300 million miles away.
Scientists from the ESA hope that Philae's onboard equipment can help them to uncover the secrets of our solar system's creation.
The comet, named 67P/Churyumov–Gerasimenko, is regarded by scientists as a frozen time capsule of information, because it thought to have been formed billions of years ago.
The Rosetta spacecraft has been orbiting the two and half mile diameter comet since August, but spent a long-time in hibernation recharging its solar cells.
It was touch and go for the team of scientists at the ESA as releasing the lander doesn't sound like an enviable task by any stretch. They had to ensure that it separated from Rosetta at exactly the right time and the right speed, because once released they would have zero control over its movement.
They also designed the Philae Lander unsure what the comet's terrain would be like, but it is thought to be dusty and quite porous, giving off an eggy sulphur-like smell.
This is the first time NASA have successfully landed an unmanned object on a moving comet. Projects in the past have attempted the feat, but were all destroyed upon impact.