pace, as Douglas Adams wryly pointed out, is very big. So staggeringly huge, you’d think that once we had lost something as small as the Philae comet probe, it would stay lost forever. Philae is, after all, only about as large as a washing machine. The comet it is sitting on is the size of the Eiger. And they are both about 300 million miles from Earth.

But on Saturday night, Philae – whose solar batteries went flat seven months ago, after an unfortunate landing – came back from the dead, radioing a message home: “Hello Earth, can you hear me?” The scientists in charge of the lost-then-found probe are overjoyed. Philae has seven cameras: we may now even get to see, close up, the spectacle of a comet “firing up” as it nears the Sun and emits a geyser-like tail of evaporating ices and dust.

Mostly, the story of space exploration is the story of robots like Philae. Human explorers have visited the moon and journeyed into low-Earth orbit, but to date no further. Our emissaries to the solar system and beyond have been machines – hugely expensive, massively sophisticated, some of the most complex devices ever built. And what is surprising is the affection they have engendered, a concern for their safety apportioned to few other inanimate objects.

Who can forget poor Beagle 2, which we all assumed became a smear of metal debris scattered across the surface of Mars on Christmas Day 2003? When no signal was received, it was concluded that its landing systems had failed.

But, then, on January 16 this year, Beagle 2 was found by the gimlet-eyed camera of another, orbiting probe, intact and on the surface of the Red Planet just where its makers had planned. Something had gone wrong – its radio transmitter had not been deployed – but the Beagle did land, not crash. It is the size of a suitcase; Mars has a surface area of 56 million square miles. And at the time of discovery Earth was more than 120 million miles away. “Needle in a haystack” does not begin to cover it.

Perhaps the greatest backfrom-the dead triumph of space exploration was the extraordinary rescue of the Galileo mission to Jupiter. Galileo was a giant Nasa probe, launched in 1989 amid great fanfare. It cost nearly $2 billion, was equipped with nuclear batteries and contained some of the most complex instruments ever sent into space. It was hoped Galileo would solve, among other things, the mystery of Europa, a large moon of Jupiter which was thought to be home to a giant ocean of water under its icy surface.

But when Galileo was still only half way to its destination, disaster struck: its main radio antenna jammed like a stuck umbrella. No antenna meant zero chance of sending data back to Earth. But, in one of the most impressive repair-jobs in history, a small back-up transmitter was reconfigured on the fly, and the whole of Galileo’s computer system was reprogrammed. All from a distance of half a billion miles. The mission was saved, and the Europan ocean duly identified.

There’s something about these plucky space robots that captures our imagination as we watch their epic quests from planet Earth. Perhaps it is because they can slip the surly bonds of earth and go where we cannot.

One of the first cyberspace “hits” was the Pathfinder probe to Mars in 1997, whose flood of pictures sent back home had the same effect on the then youthful internet as Kim Kardashian’s bottom did more recently. Beagle’s heroic failure touched the nation’s heartstrings. And now little Philae, sitting on a comet – a comet! – is spluttering back into life, ready to complete its mission.

Tears have been shed in mission control, tears not for a mere tool or instrument, but for a colleague whose death had been greatly exaggerated.