Rosetta becomes first Spacecraft to Orbit Comet

After a 10-year chase taking it billions of miles across the solar system, the Rosetta spacecraft made history Wednesday as it became the first probe to rendezvous with a comet on its journey around the sun.

"Thruster burn complete. Rosetta has arrived at comet 67P. We're in orbit!" announced the European Space Agency, which is leading the ambitious project, on Twitter.

Rosetta fired its thrusters on its final approach to Comet 67P/Churyumov-Gerasimenko, known as "Chury" for short, on Wednesday morning. Half an hour after the burn, scientists announced that the craft had entered into the orbit of the streaking comet.

"After 10 years, five months and four days travelling towards our destination, looping around the Sun five times and clocking up 6.4 billion kilometers, we are delighted to announce finally 'we are here'," said Jean-Jacques Dordain, ESA's Director General, in a statement.

"Europe's Rosetta is now the first spacecraft in history to rendezvous with a comet, a major highlight in exploring our origins. Discoveries can start."

ESA tweeted a photo of the comet after Rosetta's maneuver. Chury and the space probe now lie some 405 million kilometers from Earth, about half way between the orbits of Jupiter and Mars, according to ESA.

The mission has now achieved the first of what it hopes will be a series of historic accomplishments. In November mission controllers aim to place the robotic lander Philae on the surface -- something that has never been done before.

Previous missions have performed comet fly-bys but Rosetta is different. This probe will follow the comet for more than a year, mapping and measuring how it changes as it is blasted by the sun's energy.

Mission controllers had to use the gravity of Earth and Mars to give the probe a slingshot acceleration to meet its target on the right trajectory. Rosetta also had to be put into hibernation for more than two years to conserve power before being woken up successfully in January this year.

Wednesday's thruster burn was the tenth rendezvous maneuver Rosetta has performed since May to get the probe's speed and trajectory to align with the comet's -- and if any of those operations had failed, the mission would have been lost, according to ESA.