Rosetta and its mission

Space probe chases a comet around the Sun in a quest to find answers about our origins.

Rosetta’s mission

Catch a falling star and search it for clues about the origin of life on Earth. It’s a big ask but in essence that is what the Rosetta mission is all about.

Rosetta’s target, Comet 67P/Churyumov-Gerasimenko, isn’t a star of course -- more of a dirty snowball -- but it may hold the answer to whether our home planet was seeded with water and possibly the chemicals that make up the building blocks of life.

Led by the European Space Agency (ESA) with a consortium of partners from Europe and the United States, ESA says the primary aim of the mission is to shed light on the origin and evolution of the solar system.

Find out how the probe reached the comet.

Until now we have only gained fleeting glimpses of these lumps of rock and ice that wander the solar system, either through telescopes or from probes. Giotto made a fly-past of Halley’s Comet in 1986 while NASA’s Stardust mission collected material after flying through the tail of Comet Wild 2 and returning the sample to Earth.

Rosetta is an even more ambitious project that if successful will notch up a series of firsts.

It will be the first mission to orbit a comet’s nucleus and follow its track. This has required a decade-long planetary ballet as space engineers used the Earth and Mars to accelerate the spacecraft to a trajectory that allows it to escort Comet 67P/C-G on its journey around the Sun. It was such a long route to the cold regions of the outer solar system that Rosetta had to be put into hibernation for more than two years to conserve power.

Rosetta spacecraft

On August 6 ESA announced that Rosetta had made the rendezvous and returned images showing boulders, craters and steep cliffs.

It will also be the first landing on a comet. Philae, the robotic lander that accompanies Rosetta, is due to touch down in November 2014 where it will drill into the comet and take samples to be analyzed on board. The mission is fraught with risks: gravity is so weak on 67P/C-G that Philae has to fire a harpoon into the surface to keep it anchored to the comet.

ESA project scientist Matt Taylor told CNN: “With these firsts it will enable us to make a quantum leap in our understanding of comets -- where they come from, their consistencies.”

ESA’s Website adds: “Did life on Earth begin with the help of comet seeding? Rosetta may help us to find the answer to this fundamental question.”

You can follow the mission on Twitter at @ESA_Rosetta and on ESA’s Rosetta blog at

“Did life on Earth begin with the help of comet seeding?”