Rosetta: 'sexiest, most fantastic' space mission enters final phase

An artist's impression of the Rosetta spacecraft with Mars in the background

Spacecraft has caught up with comet in a decade long chase in search for answers about life on earth

LAST UPDATED AT 11:47 ON Wed 6 Aug 2014

The Rosetta spacecraft has now approached a speeding comet in deep space as a decade-long mission, which scientists hope will reveal more about how life on earth began, reached a climax.

Dr Matt Taylor, one of the lead scientists from the European Space Agency (ESA) watching Rosetta as it closes in on its target, calls it the "sexiest, most fantastic mission there's ever been". It ticks all the boxes in terms of "fascination, exploration, technology, and science", he tells the BBC.

What is Rosetta?

Named after the Rosetta Stone, the spacecraft was launched in 2004 by the European Space Agency (ESA). It is the first spacecraft ever designed to orbit and land on a comet.

The robotic space probe cost over €1bn to create and scientists hope that the mission will deliver answers about the composition of comets and their link to life on earth.

What's happening?

Rosetta has finally caught up with the comet, which is hurtling through space at 135,000km/h. Scientists hope to reduce the distance between the spacecraft and comet to less than 30km and Rosetta will then prepare to enter the comet's orbit in the coming weeks.

Taylor says the team needed to take "baby steps" as Rosetta makes its approach because "we don't know exactly how the comet is behaving and how the spacecraft will behave around it".

Rosetta will continue to orbit the comet for the next few months, mapping it and gathering data to help scientists prepare for the launch of the Philae Lander, which will be fired onto the surface of the comet in November. When it lands it will attach itself to its speeding host with harpoons.

What do scientists already know about the comet?

Known as 67P/Churyumov-Gerasimenko or 'Chury' for short, the comet is believed to be roughly the size of Mont Blanc, The Guardian reports, but it has an unusual irregular shape. 

Because of its strange dimensions, scientists have already dubbed it the floating "rubber duck" in space. The reason for its bizarre form is unclear, with some speculating that could be a result of an impact with other objects in space.

Scientists say it is travelling at speeds of up to 135,000km/h, but little else is known about Rosetta's quarry. 

What are they hoping to discover?

Once scientists have orchestrated the Philae Lander's descent onto the surface of the speeding comet, it will start to measure the density and composition of Chury, as well as test for the presence of amino acids, the essential building blocks of life.

Why is this so important?

As comets are the "remnants" of the beginning of the solar system, scientists hope that this mission will give them more insight into how they evolved and more importantly, whether they can be linked to the beginning of life on Earth. Some scientists believe comets delivered water, carbon and amino acids to earth. 

"The biggest question that we are trying to get an answer to is: where did life on Earth come from?" says Professor Monica Grady of the Open University, who helped design the landing craft. "How did life get going? Was it the building blocks of life that were brought to us from comets or did it get going on Earth?" · 

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