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Pictures: Best space images of 2013

Check out some of the best pictures snapped by robotic space explorers and astronauts during 2013.
In 2013, Nasa celebrated a year of discoveries by the Curiosity rover on Mars. The robot has found evidence for the presence, billions of years ago, of water that had the potential to support simple life forms.
Curiosity rover
This photo was taken by astro-photographer Damian Peach in November of comet Ison as it passed.
Comet Ison
Resembling raindrops, the blue features here are actually sand dunes on Mars. The dunes are rich in the mineral olivine and are rare on Earth because olivine turns to clay in a wet environment, but on Mars it creates this great image!
Dunes in Copernicus Crater
The spinning vortex at Saturn's north pole is pictured here from Nasa's Cassini spacecraft. Scientists think that the eye of this storm measures around 1,250 miles across, with clouds moving as fast as 150 metres a second!
Storm at Saturn's north pole
In May the Sun unleashed four intense bursts of radiation, or flares. These flares are the most intense type known to be released by the Sun. This picture from Nasa's Solar Dynamics Observatory shows the first of these flares in May.
Solar flare
This colourful view of the planet Mercury was put together from thousands of images acquired by Nasa's Messenger spacecraft. The view is not how we would see Mercury but instead it represents the variations in the composition of the planet's rock.
Mercury map
Canadian astronaut and International Space Station commander Chris Hadfield's singing in space was one of the most memorable news events of the year. The "first music video in space" went viral when it was released online in May 2013.
Chris Hadfield
One of the many amazing images taken by Commander Chris Hadfield on the International Space Station, this shows a rock outcrop in Brazil. Commander Hadfield said that he had no idea what it looked like on the ground, "but from orbit, it's a brain"
Rock outcrop in Brazil
And in December, China landed a rover on the Moon - the first landing of its kind for 37 years. It was a big step for Chinese space authorities who say one day they hope to send a man to the Moon too.
Jade Rabbit rover