Scientists from the European Space Agency (ESA) announced Wednesday that the Philae probe touched down successfully on comet 67P/Churyumov-Gerasimenko, the first time a spacecraft has landed on a comet.

This landmark scientific achievement follows the probe's 10-year, 4 billion mile journey.

Fox News reported:

The separation, which took place around 4 AM ET, marked the start of a 7-hour journey to the comet’s surface. The Rosetta spacecraft and its Philae lander have been on a decade-long mission through the solar system to rendezvous with the comet.

The comet, which is about 2.5 miles wide, travels at speeds up to 84,000 miles per hour.

The washing machine-sized lander drifted down to the comet and latch on using harpoons and screws. During the descent, scientists were powerless to do anything but watch, because the vast distance to Earth — 311 million miles — made it impossible to send instructions in real time.

The plan is that Rosetta and Philae will accompany the comet as it hurtles toward the sun and becomes increasingly active as it heats up. Using 21 different instruments, they will collect data that scientists hope will help explain the origins of comets and other celestial bodies.

The $1.6 billion mission launched in 2004.

Watch the "Happening Now" report below and check out incredible photos of the Philae probe and the comet in these photographs from the ESA/Rosetta.

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Comet 67P/C-G seen from the European Southern Observatory's very powerful telescope.

The comet's head, where Philae successfully landed this morning.

The white cross marks the intended landing site.

The Rosetta spacecraft, with a 105-foot wingspan, is the mothership that the washing machine-sized Philae probe detached from.

One of Rosetta’s 46-foot long solar wings, with the comet in the background.

Philae's parting shot of its mothership shortly after separation.

Rosetta’s parting image of Philae as the lander begins its seven-hour descent to the comet's surface.

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Watch the "Happening Now" report:

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