Europe's comet chaser begins journey

After more than a year of aborted attempts, a European-built rocket blasted off Tuesday on a decade-long mission to land a probe on a comet and explore the origin of the solar system.

As flight engineers and scientists applauded, an Ariane-5 rocket lifted off into the night sky in Kourou, French Guiana at 2:17 a.m. EST.

About two hours later, ground controllers said the Rosetta spacecraft separated from the rocket. To escape Earth's gravity, the spacecraft received a boost by delaying ignition of an engine in its upper stage.

"We received the first communication from the spacecraft, which means the spacecraft is in good shape at the moment," said Gaele Winters, director of operational and technical support with the European Space Agency, at mission control in Darmstadt.

European space officials and scientists in Darmstadt toasted the successful launch of the $1.25-billion US mission with champagne.

Rosetta is expected to catch up to a four-kilometre-wide comet called 67P/Churymov-Gerasimenko in May 2014, go into orbit around it and then drop a miniature laboratory.

The comet's gravity is so weak that the lander will use a harpoon and spikes to claw into the surface before it can test the icy composition and drill for samples.

Earlier missions have only flown by comets.

Comets are thought to contain chemical and physical evidence dating back 4.5 billion years. The material may help scientists understand how the solar system formed.

One theory suggests when comets bombarded Earth, they seeded our planet with the chemical building blocks for life water and organic materials.

Before arriving at the comet, Rosetta will swing around Earth and Mars four times, gaining velocity for the deep space trip.

The Rosetta probe is named for the Rosetta Stone tablet that helped researchers decipher Egyptian hieroglyphic writing.