After a 10-Year Trip, the First Satellite Tasked to Land on a Comet Has Reached Its Target

(TheBlaze/AP) — After traveling more than 4 billion miles during  a 10-year journey, an unmanned satellite finally reached its target: a comet between the Mars and Jupiter orbits.

Europe's Rosetta probe reached comet 67P/Churyumov-Gerasimenko Wednesday, a milestone in mankind's first attempt to land a spacecraft on a comet.

Rosetta’s OSIRIS narrow-angle camera snapped this picture of Comet 67P/Churyumov-Gerasimenko after the comet chaser finally reached its target Wednesday Aug 6, 2014. Rosetta had to perform a series of complex maneuvers to gain enough speed to chase down the comet on its orbit around the sun. (AP Photo/ESA/Rosetta/MPS for OSIRIS Team)

Described by ESA scientists as "the sexiest, most fantastic mission ever," Rosetta spent the early Wednesday hours conducting a series of maneuvers and thruster burns to arrive within 60 miles of the comet, according to Gizmodo.

The decade-long trip -- where Rosetta traversed the solar system topping 34,000 mph -- was successfully completed with a seven-minute thrust that allowed Rosetta to swing alongside the icy celestial body and enter it's orbit. This style of mission has never been attempted before, and the team had to overcome significant hurdles, like delayed radio signals that take 22 minutes to travel between Earth and the spacecraft.

"This is your only chance to have a rendezvous with a comet," Jean-Jacques Dordain, director-general of the European Space Agency, told scientists and spectators at the mission control center in Darmstadt, Germany.

Rosetta performed a series of complex maneuvers to gain enough speed to chase down the comet on its orbit around the sun, including three loops around Earth and one around Mars.

The satellite will orbit 67P just 60 miles from it's surface and observe the comet as it hurtles toward the sun. If all goes according to plan, Rosetta will attempt the unprecedented feat of dropping a lander -- dubbed Philae -- onto the comet in November.

The European/Rosetta mission is different from NASA's Deep Impact spacecraft, which fired a projectile into a comet in 2005 to study the resulting plume of matter. NASA also landed a probe on an asteroid in 2001, but comets are much more volatile places because they constantly release dust and gas that can harm a spacecraft.

Scientists hope the information they collect will inform them about the origins of comets, stars and planets, David Southwood, who oversaw some scientific considerations of the mission until his recent retirement, said.

"Comets are the stuff of which the solar system was originally made," he said. Some scientists have suggested water, an essential element for biological development, arrived on Earth from comets.

Initial plans to bring material extracted from the comet back to Earth were canceled when NASA pulled out of a joint mission at an early stage, but the U.S. space agency contributed three of the 21 instruments aboard Rosetta and its Philae lander.

Scientists have already made a number of interesting observations; released pictures taken by Rosetta show that 67P has an uneven shape that some have likened to a giant, 2.5 mile-long duck. This could mean the comet is made up of two formerly distinct objects, or that it was heavily eroded.

The images, which have a resolution of eight feet per pixel, also show steep 490-foot cliffs as well as smooth plains and house-sized boulders.

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ESA released an artist's rendering of the Rosetta comet chaser, which they hope will be the first spacecraft became the first to rendezvous with a comet and will follow it on the journey around the sun. (European Space Agency)

Scientists will spend the coming months analyzing the pictures Rosetta sends home to determine the best place to drop Philae. The lander will glide down to the comet before shooting a harpoon into its porous surface to avoid drifting off again.

Apart from the unprecedented landing, the orbiter section will also be the first to accompany a comet on its journey toward the sun, when 67P will begin to fizz and release the cloud of dust and ice that most people associate with comets. Measurements show that the comet is already losing the equivalent of two small glasses of water each second, an amount that will increase thousand-fold over the coming months.

"We're going to have a ringside seat to see, for the first time, a comet turn into a comet, to develop its tail and explain what for centuries mankind has been puzzled by," Southwood said.

So why all the fuss about a comet?

While the water-filled space rocks have long been associated with superstition, there is a real -- albeit slim --chance that such an object could one day hit Earth, causing a global catastrophe. Learning more about the nature of comets might help prevent those events, Southwood said.

The spacecraft and its lander won't survive much beyond the end of next year, but the data they collect are expected to keep scientists busy for at least a decade. So far, the Rosetta project has cost $1.74 billion.

If nothing else, take a moment to check out this interactive simulation, and appreciate the math required to make this happen, especially the perfectly-timed planetary fly-bys:

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