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The New Horizons spacecraft has taken its first colour image of Pluto and its largest moon Charon ahead of its arrival in three months.

Taken from a distance of 71 million miles (115 million km), the blurry image doesn't reveal a huge amount of detail - but it is a sign of things to come.

As the spacecraft gets closer and closer, the images will continue to improve until it flies by on 14 July - humanity's first ever visit to Pluto.

Nearly there: After more than nine years, the New Horizons spacecraft is now just three months away from its historic encounter with Pluto. And now the spacecraft has taken its first colour image, shown, revealing the dwarf planet (the bigger blob) and its moon Charon

After a journey of more than nine years, Nasa's New Horizons spacecraft is now reaching the climax of its thrilling mission.

It has traveled longer than any space mission in history to reach its primary target - with its pedometer measuring more than three billion miles (4.8 billion km).

Its arrival at Pluto will be the last world in the 'classical solar system' to be explored.

Pluto was demoted from a 'planet' to a 'dwarf planet' in 2006 when other objects of a similar or greater size were found.

But regardless, the mission is of huge importance for our understanding of how bodies form even at great distances from their host star.

'New Horizons is one of the great explorations of our time,' said New Horizons Project Scientist Hal Weaver at the John Hopkins University Applied Physics Laboratory in Laurel, Maryland.

'There's so much we don't know, not just about Pluto, but other worlds like it.

'We're not rewriting textbooks with this historic mission - we'll be writing them from scratch.'

The latest image of Pluto and Charon was captured by the Ralph camera on the spacecraft from a distance equivalent to the sun to Venus.

At a relative speed of 30,000 mph (50,000km), New Horizons will cover that distance in just three months.

The image shows Pluto with a sort of reddish colour and Charon - which is just over half the size of Pluto - considerably dimmer. 

Our best images of Pluto so far are mostly attempts from Hubble - but they are not much better than this photo.

This makes the New Horizon mission particularly exciting, as it will reveal the surface of a world we know very little about. 

Not since humans first started sending spacecraft into the solar system has a comparable mission been seen.

Our best images of Pluto so far come from the Hubble Space Telescope (shown is one of the images), so the arrival of New Horizons is hugely exciting for scientists, who have waited many years to catch a glimpse of this distant world and unravel some of its secrets

New Horizons (artist's illustration shown) was launched on 19 January 2006 at a speed of 36,373 mph (58,536 km/h) - the fastest spacecraft ever to leave Earth orbit, 100 times faster than a jetliner. Owing to the speed of New Horizons, the observations of Pluto will last just two hours

The flyby caps a five-decade-long era of reconnaissance that began with Venus and Mars in the early 1960s, and continued through first looks at Mercury, Jupiter and Saturn in the 1970s and Uranus and Neptune in the 1980s.

'Scientific literature is filled with papers on the characteristics of Pluto and its moons from ground based and Earth orbiting space observations, but we've never studied Pluto up close and personal,' said John Grunsfeld, Nasa Science Mission Directorate.

'In an unprecedented flyby this July, our knowledge of what the Pluto systems is really like will expand exponentially and I have no doubt there will be exciting discoveries.'

Such is the mystery of Pluto that astronomers are not even sure what they will find on the surface. 

Pluto, the largest known body in the Kuiper Belt, is thought to have a nitrogen atmosphere and complex seasons.

On its surface, it seems to have distinct markings, and it may have ice as well.

The dwarf planet may even harbour an underground ocean.  

Among its five known moons, the largest - Charon - may itself sport an atmosphere or an interior ocean, and possibly even evidence of recent surface activity.

Owing to the speed of New Horizons, the observations of Pluto will last just two hours.

But it will collect a huge amount of data on Pluto and its moons, revealing unprecedented views - and with no other missions to Pluto in the pipeline, they will be our only images for a very, very long time.

'This is pure exploration; we're going to turn points of light into a planet and a system of moons before your eyes!" said Alan Stern, New Horizons principal investigator from the Southwest Research Institute (SwRI) in Boulder, Colorado. 

'New Horizons is flying to Pluto - the biggest, brightest and most complex of the dwarf planets in the Kuiper Belt.

'This 21st century encounter is going to be an exploration bonanza unparalleled in anticipation since the storied missions of Voyager in the 1980s.'

Not since Voyager 2 (illustrated left) flew past Neptune (right) in 1989 and started taking pictures has such a reconnaissance mission been attempted. New Horizons' mission represents the last of the worlds in the 'classical solar system' to be explored - and will be our sole visitor to Pluto for many, many years

Scientists still know very little about Pluto (illustrated left), its largest satellite Charon (right) and its other moons. Pluto, the largest known body in the Kuiper Belt, is thought to have a nitrogen atmosphere and complex seasons. On its surface, it seems to have distinct surface markings, and it may have ice as well

Pluto's smaller moons also are likely to present scientific opportunities. When New Horizons was started in 2001, it was a mission to just Pluto and Charon, before the four smaller moons were discovered.

The spacecraft's suite of seven science instruments - which includes cameras, spectrometers, and plasma and dust detectors - will map the geology of Pluto and Charon and map their surface compositions and temperatures.

The spacecraft will also examine Pluto's atmosphere, search for an atmosphere around Charon, study Pluto's smaller satellites and look for rings and additional satellites around Pluto.

Currently, even with New Horizons closer to Pluto than Earth is to the sun, the Pluto system resembles little more than bright dots in the distance.

But teams operating the spacecraft are using these views to refine their knowledge of Pluto's location, and skillfully navigate New Horizons toward a precise target point 7,750 miles (12,500 kilometers) from Pluto's surface.

That targeting is critical, since the computer commands that will orient the spacecraft and point its science instruments are based on knowing the exact time and location that New Horizons passes Pluto.

This image, taken by Nasa's Hubble Space Telescope, shows five moons orbiting the distant, icy dwarf planet Pluto. Styx (initially designated P5), is the innermost of the moons found by Hubble over the past seven years. This image was taken with Hubble's Wide Field Camera 3 on 7 July 2012

'Our team has worked hard to get to this point, and we know we have just one shot to make this work,' said Alice Bowman, New Horizons mission operations manager at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland.

'We've plotted out each step of the Pluto encounter, practiced it over and over, and we're excited the "real deal" is finally here.'

The spacecraft's work doesn't end with the July flyby. Because it gets one shot at its target, New Horizons is designed to gather as much data as it can, as quickly as it can, taking about 100 times as much data on close approach as it can send home before flying away.

And although the spacecraft will send select, high-priority datasets home in the days just before and after close approach, the mission will continue returning the data stored in onboard memory for a full 16 months. 

And beyond Pluto, Nasa is also planning to study one or two Kuiper Belt Objects (KBOs) with New Horizons in the years after its historic primary mission.