Look for the moment beyond the sordid argument about Greek debt, the mean-spirited management of the refugee confrontations in Calais, the murderous bitterness in the Ukraine. Forget the grotesque posturing of would-be Republican candidates in the US.

Far away – more than 102m miles away but moving very fast – the European space probe Rosetta is escorting comet 67P/Churyumov-Gerasimenko on its journey to perihelion, its closest approach to the sun. This is the point at which the dust and gas blasted from the comet’s surface will be at its maximum, and, through Rosetta, humans will witness close at hand for the first time one of those mysterious celestial firework displays interpreted for 3,000 years as portents of wonderful or dreadful things to come. Meanwhile, even further away, a US space probe called New Horizons, travelling at 34,000mph, has already sped past what has traditionally been considered the ninth planet, Pluto, and its moon Charon.

To make either of these things happen, small cabals of scientists from all over Europe, Asia and America had to dream the impossible, formally propose it, argue the case for it, and devise the technology first to make it happen and then to make it worthwhile. In each case, this process began in the last century, in a space agency with a record of ambitious failures to live down, and with computing power that would now seem laughable. The senior scientists and administrators who evaluated both and signed the authorisations, and the government ministers who committed the money, are now mostly forgotten and many of them are already dead.

Every step was openly taken, and every decision could be challenged. Although the first proposers had formulated the questions they hoped to answer, nobody at any point could say with certainty what rewards either mission could deliver. Each was, in every sense, a journey into the unknown. The climax of each mission may occur this summer, but each space probe will go on delivering discovery for as long as it has the power to do so. One of them will follow a comet into the darkness for at least a year while the other will go on to the Kuiper Belt, that unimaginable region from which many of the comets come. None of the engineers or scientists involved in either mission joined the project for fame or fortune. Each achievement represents a triumph for far-sighted cooperation and intellectual generosity. To make these missions happen, researchers had to develop and perfect technologies from which medicine and industry will benefit – and in some cases do so already – but nobody at the time thought a lot about of patents, or royalties to come.

Both are exemplars of open and generous partnership, and scientists and politicians and civil servants from Russia and America, Ukraine and Greece, France, Britain and many other nations can decently claim credit. Rosetta is a gleaming instance of what Europe collectively can do so well, while Calais and the Greek debt crisis are sorry examples of what it fails to do well. Each mission will enter the history books as a triumph. All of which is more than can be said for the bickering and frustration in Brussels, Berlin and Athens, at border posts on either side of the Channel, or in the corridors of power in Kiev and Moscow.