An ambassador to Neptune's kingdom

THERE has, in recent years, been much talk of holidays in space. Though things have not gone well for one aspiring space-tourism business, Virgin Galactic, whose prototype suborbital rocket plane blew up on a test flight in October, those with truly deep pockets can still book a trip to the International Space Station courtesy of an American firm called Space Adventures that arranges seats on Russian launches. But for people who cannot quite stretch to the $20m or so such a trip will cost, there...