Rosetta’s 11-year expedition began in March 2004, with an Ariane 5 launch from Kourou in French Guiana. Using three Earth-gravity assists (2004, 2007, 2009) and one at Mars (2007), the spacecraft was propelled towards the outer Solar System. It has encountered two asteroids, (2867)Steins in 2008 and (21)Lutetia in 2010, and is now cruising to its final destination.

Rosetta will reach the comet in 2014, and will be the first mission ever to orbit a comet’s nucleus and to deliver a lander, called Philae, on its surface.

Credits: ESA, image by AOES Medialab

Rosetta’s 11-year expedition began in March 2004, with an Ariane 5 launch from Kourou in French Guiana, and the spacecraft was then sent towards the outer Solar System. The long journey includes three gravity assists at Earth (2004, 2007, 2009), one at Mars (2007), and two asteroid encounters: (2867) Steins (2008) and (21) Lutetia (2010).

After the third Earth-gravity assist and a large deep-space manoeuvre, the spacecraft will go into hibernation (July 2011 – January 2014). During this period, Rosetta will record its maximum distances from the Sun (about 800 million kilometres) and Earth (about 1 thousand million kilometres). The spacecraft will be reactivated prior to the comet-rendezvous manoeuvre, during which the thrusters will fire for several hours to slow the relative drift rate between the spacecraft and comet to about 25 m/s.

Credits: ESA, image by AOES Medialab

Rosetta’s task is to study these primitive building blocks at close quarters so that scientists may gain new insights into the events that took place 4600 million years ago, during the birth of Earth and its planetary neighbours.

Credits: ESA and European Southern Observatory

Selected in November 1993 as a cornerstone mission of ESA's long-term science programme, the Rosetta probe was launched by an Ariane 5 on 2 March 2004, on an 11-year journey to the Comet 67P/Churyumov-Gerasimenko.

Built by EADS Astrium, the Rosetta probe consists of a 3065-kg spacecraft (1578 kg dry mass) designed to enter orbit around the comet's nucleus in August 2014 after a series of gravity assist manoeuvres to gain enough orbital energy, with three swing-bys at Earth (March 2005, November 2007 and November 2009) and one at Mars (February 2007). En route to the comet, the probe will fly-by the asteroids (2867) Steins (September 2008) and (21) Lutetia (July 2010).

The spacecraft carries 11 science instruments to probe the comet's nucleus and map its surface in fine detail. It will also land a package of instruments (the Philae lander) to study some of the most primitive, unprocessed material in the Solar System. The mission will provide clues to the physical and chemical processes at work during the formation of planets, beginning 4600 million years ago.

Credits: ESA, image by AOES Medialab