Rosetta scientists target comet's head

After a 10-year chase taking it billions of miles across the solar system, the European Space Agency's Rosetta spacecraft became the first probe to orbit a comet after arriving at its destination on August 6. The spacecraft recently took this image of comet 67P/Churyumov-Gerasimenko. In November, Rosetta will deploy a robotic lander to the comet's surface -- something that also has never been done before. The box on the right shows where the lander will touch down.

The spacecraft sent this image as it approached the comet on August 6. From a distance of 130 kilometers (nearly 81 miles), it reveals detail of the smooth region on the comet's "body" section.

This image, captured August 7, shows the diversity of surface structures on the comet's nucleus.

The comet's "head" can be seen in the left of the frame as it casts a shadow over the "body" in this image released August 6.

This image of the comet was taken on August 1.

Rosetta's mission started on March 2, 2004, when it was launched on a European Ariane 5 rocket from Kourou, French Guiana.

Rosetta is named after the Rosetta Stone, the black basalt that provided the key to deciphering Egyptian hieroglyphs. Scientists think the mission will give them new clues about the origins of the solar system and life on Earth. The mission is spearheaded by the European Space Agency with key support from NASA.

This photo shows Rosetta being tested before it was wrapped in insulating blankets and loaded on a rocket for launch.

Rosetta has massive solar wings to power the spacecraft. They were unfurled and checked out at the European Space Agency's test facilities before being packed up for liftoff.

After its closest approach to Earth in November 2007, Rosetta captured this image of the planet.

Rosetta snapped this image of Earth in November 2009. The spacecraft was 393,328 miles from Earth.

Rosetta passed asteroid Steins in September 2008, giving scientists amazing close-ups of the asteroid's huge crater. The asteroid is about 3 miles in diameter.

Rosetta took this image of Mars as it looped through the solar system.

This image was taken by an instrument on Rosetta's Philae lander just minutes before the spacecraft made its closest approach to Mars. Part of Rosetta and its solar arrays are visible.

On July 10, 2010, Rosetta flew about 1,864 miles from asteroid Lutetia, which is 10 times larger than asteroid Steins.

Look closely at the top of this picture. See that dot? That's Saturn. Rosetta snapped the picture of asteroid Lutetia and captured Saturn in the background.

After taking pictures of Earth, Mars and asteroids, Rosetta was put into hibernation in May 2011 after it reached the outer part of the solar system. Mission managers woke it January 20, 2014.

In November, Rosetta will become the first spacecraft to deploy a robot for a soft landing on a comet. It also will be the first probe to escort a comet into our inner solar system. This drawing shows how Rosetta will drop its robot lander, Philae, onto the comet.

The robot lander will fire harpoons to anchor itself to the comet. Scientists expect the lander to send back data to Earth for at least a week and possibly for many months as the comet heads toward the sun.

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• Scientists are trying to land a probe on Comet 67P/Churyumov-Gerasimenko


• The European Space Agency says it now has chosen a prime target landing site


• The comet is so far from Earth the Philae lander needs to be programed to land on its own


• It took more than 10 years to position the Rosetta craft so it could follow the comet

London (CNN) -- Scientists have picked a prime landing site on the "head" of a comet for the next stage of the Rosetta mission.

The project, led by the European Space Agency (ESA) with partners including NASA, recently placed the Rosetta probe in an orbit 30km (18 miles) from the surface of Comet 67P/Churyumov-Gerasimenko after a 10-year chase across the solar system.

If successful, the mission will be the first to orbit and land on a comet as it journeys around the Sun.

A statement on the space agency's Rosetta blog says landing site "J" was chosen due to its "scientific potential" while posing less risk to Rosetta's lander module Philae compared to other possible sites.

A backup site (marked "C" in the above composite image) has been identified on the irregularly-shaped "body" of the comet which has two distinct lobes -- and mission controllers say they are aiming to reach the surface on November 11.

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Dave Brody explains comet mission

Rosetta probe to explore human origins

Rosetta will stay in orbit around the comet as it rushes towards the Sun, taking measurements as gas and dust are ejected into a huge tail, while the lander carries out experiments on the surface.

The mission is aimed at learning more about the composition of comets and the project may shed light on whether they brought water to Earth or even the chemicals that make up the building blocks of life.

3D animation: See how Rosetta met the comet

"We will make the first ever in situ analysis of a comet at this site, giving us an unparalleled insight into the composition, structure and evolution of a comet," said a lead lander scientist Jean-Pierre Bibring on ESA's Rosetta website.

Making a landing is particularly difficult as the probes are so far away that steering Philae once it has separated from Rosetta is not possible. The lander's trajectory has to be programmed ahead of its release.

Project leaders had to find a landing site that avoids large surface hazards and allows Philae to continue to communicate with Rosetta.

Before the prime landing site was chosen, Rosetta project scientist Matt Taylor also explained that power was a crucial consideration.

We are starting to sniff and taste the comet.

Matt Taylor, Rosetta project scientist

Philae's batteries will have enough charge for 64 hours but the lander needs sunlight to generate more energy for the extended science mission.

"There are certain parts of the comet where you won't be able to do any science because you will never get the lander in enough sunlight to be able to recharge the batteries," Taylor told CNN.

Taylor shared the excitement of seeing the first high-resolution close-up images but said his reaction to the odd shape was: "What are we going to do with this? Where are we going to go?

"It has presented a challenge as to where we can land on the comet because there are certain regions you just can't reach. The neck is quite difficult to get to -- it's difficult to get a trajectory that will end up on that point without clipping one of the lobes."

Taylor told CNN that results were starting to come in from the on-board instruments.

"There are some dust instruments that kind of put their hand up for a couple of weeks and then bring the hand back in again and analyze what it's caught," he said.

"We are starting to sniff and taste the comet."

You can follow Rosetta's mission on Twitter @ESA_Rosetta and through the ESA blog.

READ: Interactive coverage of Rosetta mission on CNN

READ: Rosetta first to orbit comet