Many of us spend Christmas far from friends and family, but Richard Hollingham spares a thought for those farthest flung of all – our spacecraft exploring the Solar System and beyond.

In July 1965, Mariner 4 became the first space probe to send back pictures of another world from space. Fifty years on, not only do several spacecraft orbit the same red planet, but there are also two active rovers on the Martian surface and new missions being prepared for launch.

There are also spacecraft in orbit around Mercury, Venus and Saturn, a lander on a comet, another on a distant moon, and that’s on top of the many space telescopes probing the depths of the cosmos.

As the festive season approaches and we think of far-flung friends, it’s worth spending a thought on those farthest flung of all – all in the name of science and our understanding of the Universe. Here then, for a truly spacey festive season, are our 12 missions of Christmas in order of increasing time spent away from our planet (note all distances are approximate averages):

#12: Hayabusa 2

Distance from home: Recently left Earth orbit

Time away: Three weeks

When it comes to asteroid expertise, then the Japanese space agency leads the way. In 2010, its first Hayabusa mission brought back to Earth a sample of asteroid Itokawa.

The latest mission, Hayabusa 2, launched on 3 December 2014. It involves rendezvousing with another asteroid, landing a probe and sending out a mini-rover to explore. However, unlike all the other missions in our list, this spacecraft (or at least part of it) is designed to return to Earth.

#11: Gaia

Distance from home: 1.5 million kilometres (932,000 miles)

Time away: One year

For a perfect view of the cosmos, you need to head for a Lagrange point – regions of space where the movement and gravitational forces of the spacecraft, Sun and planet effectively cancel each other out. At one of these points – known as L2 – sits Gaia, an ambitious European Space Agency (ESA) mission designed to produce a 3D map of the entire Milky Way.

The largest camera ever flown in space, Gaia, Gaia is charting the position, movement and changes in brightness of every star in the galaxy, and is also expected to discover new planets, asteroids and supernovae.

#10: Maven

Distance from home: 225 million kilometres (139 million miles)

Time away: 13 months

Although every mission to the second-most-studied planet in the Solar System (after our own) deserves a mention, Nasa’s Maven (Mars Atmosphere and Volatile EvolutioN) is first to tackle the fundamental question: what happened to Mars’ atmosphere?

There is increasing evidence that millions of years ago Mars was a warmer, wetter world, shrouded in a thick atmosphere. With water flowing across the surface, it had all the right conditions for life. Maven is measuring what is left of the Martian atmosphere to help scientists piece together what went wrong. (You can read more about my thoughts on Maven here.)

#9: Lunar Reconnaissance Orbiter (LRO)

Distance from home: 384,400 kilometres (238,606 miles)

Time away: Five years, six months

You would be forgiven for thinking that Nasa lost interest in the Moon after Apollo 17 commander, Gene Cernan, left his final step in December 1972, but in reality it has never gone out of fashion. In fact the latest flurry of missions is attempting to tackle many of the questions the Apollo programme left unanswered.

In orbit around the Moon since 2009, LRO has been mapping the lunar surface in unprecedented detail. Nasa recently suggested that steep-walled pits, spotted by the orbiter, could be used as shelters by future astronauts.

#8: New Horizons

Distance from home: 4.7 billion kilometres (2.9 billion miles)

Time away: Nine years

Launched in January 2006, Nasa’s New Horizons probe has just woken up from its latest hibernation to start exploring Pluto. This distant lump of rock may no longer be classed as a proper planet (although that remains controversial) but it still holds an allure for scientists.

Pluto is at the edge of the Kuiper Belt (depending on how you define the boundary), an area riddled with small worlds, debris and moons. Fitted with multiple cameras and sensors, New Horizons will make its closest approach to Pluto on 14 July 2015 to carry out the first detailed investigation of this intriguing region.

#7: Venus Express

Distance from home: 41.9 million kilometres (26 million miles)

Time away: Nine years

All missions come to an end eventually, but despite the best efforts of controllers, Venus Express will not give up without a fight. In orbit around Venus since 2006, the ESA mission has been studying the planet’s dense and turbulent atmosphere and catching occasional glimpses of the fiery surface below.

The mission was scheduled to end last year, with a low-altitude plunge deep into the atmosphere, but the spacecraft emerged intact. With fuel for manoeuvring still remaining, mission controllers have since been trying to keep the spacecraft going as long as they can. The sad Christmas news is that Venus Express appears to have gone into ‘survival’ mode suggesting its final demise is imminent.

#6: Messenger

Distance from home: 77 million kilometres (48 million miles)

Time away: 10 years, four months

If surviving Venus is tough then visiting the closest planet to the Sun is potentially even harder. Nasa’s Messenger mission has been in orbit around Mercury since March 2011, studying the planet and taking pictures of the surface. The spacecraft is fitted with a ceramic sunshield to protect it from the 450C heat of the Sun, maintaining the instruments at room temperature.

Remarkably, despite the extreme temperatures, Messenger has confirmed that there are substantial deposits of ice on the surface. Scientists are trying to understand the age of this ice – which might give an insight into when water arrived on Earth.

#5: Rosetta

Distance from home: 510 million kilometres (317 million miles)

Time away: 10 years, nine months

The space (and physics) highlight of the last 12 months is undoubtedly Philae’s landing on comet 67P. Despite losing power and signing off with a final tweet of “I'll tell you more about my new home, comet #67P soon… zzzzz”, there is every chance the probe will wake from its slumber as 67P gets closer to the Sun.

In the meantime, the mission has already turned accepted wisdom on its head – suggesting that Earth’s water did not come from comets. It is also important to remember that the Rosetta mothership remains in orbit around 67P, so there is plenty more science to come.

#4: Opportunity rover

Distance from home: 225 million kilometres (139 million miles)

Time away: 11 years, five months

The Curiosity rover’s tweets have captured the world’s imagination (particularly the first one…look it up) and there have probably been more column inches devoted to it (certainly by this correspondent) than all the above combined. So it is easy to forget that another rover has also been trundling around on Mars for longer.

Since landing on the Red Planet in 2004, Opportunity has covered more than 40 kilometres to earn it the off-world driving record. Considering it was only supposed to last a year, this is a remarkable feat of endurance. Sadly, its twin rover Spirit went silent in March 2010 but Opportunity’s endurance bodes well for Curiosity.

#3: Cassini Huygens

Distance from home: 1.2 billion kilometres (746 million miles)

Time away: 17 years

There is some corner of a distant moon. That is forever England. A British-built instrument on the Huygens lander to be exact.

In January 2005 this tiny European space probe parachuted down to the surface of Saturn’s moon Titan. The images it sent back, before its batteries ran out, revealed a desolate hydrocarbon landscape under a smoggy petrochemical sky.

Although the Huygens probe has long since died, its US-built mothership – Cassini – continues to investigate the wonders of the Saturn system.

#2: Soho

Distance from home: 1.5 million kilometres (932,000 miles)

Time away: 19 years

What could be more seasonal than a mission following our nearest star? Soho (Solar and Heliospheric Observatory) is one of the longest-serving solar observers and has been studying the Sun since 1995.

As well as helping scientists understand the long-term processes taking place in this giant nuclear furnace, data from the satellite is also used on a daily basis to help predict space weather. This is the term used to describe all the material – particles, flares and eruptions – spewed out from the Sun that could have an effect on the Earth, causing damage to satellites or even knocking out power grids.

#1: Voyager 1

Distance from home: 19.5 billion kilometres and counting (12 billion miles)

Time away: 37 years

With a gold disk engraved with messages and sounds from Earth bolted to the side, Voyager 1 represents the loneliest outpost of human civilisation.

Voyager 1 and its sister spacecraft Voyager 2 were launched in 1977. Powered by nuclear batteries and with computers holding only 68KB of memory, they have both lasted much longer than expected. Since it left the Solar System, Nasa has rebranded Voyager 1 as the Interstellar Mission.

If nothing else, this Christmas list serves to remind us just how far space exploration has come in the past 50 years. Thanks to the endeavour and ingenuity of thousands of scientists and engineers, we can doubtless look forward to many happy new years in space to come.

Oh, and if you want to wish Voyager a Merry Christmas, set your alarm clock for 6am on Christmas Eve; radio signals take 18 hours to reach the lonely traveller from Earth.

Just how big IS space? Discover the secrets of our Solar System in this BBC Future infographic

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