Rosetta spacecraft meets comet after epic journey

Wednesday will be a big day for space fans when the Rosetta spacecraft connects with a comet and then continues to travel with the comet for the next year and a half.

The rendezvous — which has taken Rosetta 10 years and 3.5 billion miles of space travel — and the subsequent journey marks the first time a spacecraft has done more than a quick hello with a comet.

As Rosetta draws near, the European Space Agency released a new image and the first temperature measurements of comet 67P's core. The temperature data show that 67P is too hot to be covered in ice and "must have a dark, dusty crust."

The comet and Rosetta will journey together toward the sun, with Rosetta taking pictures and sampling the comet's chemicals.

Rosetta "gives you a front-seat, ride-along vision of what the comet's going to do and how a comet works," says Rosetta project scientist Matt Taylor of the European Space Agency, which is mounting the mission. "This is really a big leap forward."

As the two head toward the sun together, the growing warmth will waken the comet. Its glowing halo will expand, it will sprout several tails and Rosetta will be there to watch the whole process — another first.

Watch the rendezvous live Wednesday at rosetta.esa.int.

Contributing: Traci Watson, Special for USA TODAY