The European Space Agency's Rosetta orbiter finally started its 5 billion kilometer journey Tuesday morning after two postponements last week.
Three's a charm: Rosetta has taken off into space
Rosetta's mission to catch a comet began from the European spaceport in Kourou in French Guiana at 8:17 CET with the launch of the Ariane 5 rocket that carries the three-ton spacecraft.
Minutes after lift-off, the main booster rocket and two solid-fuel rockets separated and fell into the Atlantic Ocean. The rocket reached the Earth's orbit successfully. Then, slightly later than expected, the rocket's upper stage ignited, catapulting the craft out of the Earth's gravitational pull and into space almost two hours after its launch.
"The first step has been taken," Rosetta operations manager Manfred Warhaut said at mission control in Darmstadt, south of Frankfurt, on Tuesday. "That is a very, very good feeling."
Rosetta is now on its way to meet up with the comet Churyumov-Gerasimenko in 2014. The spacecraft's probe, Philae, is scheduled to land on the celestial body in November 2014, the first time anything of the sort will be attempted.
Last week, Rosetta's launch was delayed twice due to high winds and damage to the rocket's insulation. The €1 billion ($1.25 billion) mission was originally scheduled to begin in January 2003, but then too, technical problems with the rocket caused ESA to scratch the launch, and Rosetta missed the chance to rendezvous with the comet Wirtanen. Churyumov-Gerasimenko, named after the Soviet scientists who discovered it in 1969, was chosen instead.
Artist's impression of Philae, the Rosetta lander, which is supposed to be released onto the surface of the comet Churyumov-Gerasimenko in 2014.
Little is known about the comet, which ESA describes as a "dirty snowball." But once Rosetta catches up with it, the craft will follow it at speeds of up to 100,000 kilometers (62,000 miles) per hour for a year, while the 100-kilo (220-pound) heavy Philae maps its surface and studies its activities.
Looking for the solar system's origins
Scientists believe comets -- orbiting clusters of frozen gas and dust which date back to the beginning of the solar system -- may contain vital clues as to how the solar system was formed and maybe even how life itself began on Earth. Some astrophysicists contend that comets' complex molecules may have brought the building blocks for life to Earth when they bombarded the planet in its infancy.
The race to discover what makes a comet has been underway for decades: