Ever since H G Wells wrote War of the Worlds and described the Martians ruthlessly zapping the Home Counties, we've seen countless visions of how we might react to learning we're not alone in the universe. From government cover-ups and conspiracies to all-out interplanetary war, aliens coming to visit is a science-fiction staple.

Learning the World - a novel of first contact

In Ken MacLeod's Learning the World, however, humanity has a long way to go before meeting new life. MacLeod suggests a universe so vast that humans conquer space travel and colonise vast numbers of star systems before finally encountering intelligent life.

In this novel, we are the invaders. And most of the ship's crew has a different opinion on how to go about things.

Aboard the sunliner 'But the Sky, My Lady! The Sky!', it's clear that a lot of evolution separates the characters in the novel from you and me. The engineers are so accustomed to working in zero-gravity that they can't walk on two feet without a great deal of practice. At adulthood, young people get access to all sorts of groovy augmented abilities. You can live for centuries.

But the spirit of the 21st Century teenager is alive and well in young Atomic Discourse Gale, who writes a pretentious blog called 'Learning the World'. Although she misses out the poems about dead pets, and hilariously captioned cat photos.

MacLeod's choice of narrator for the sections of the novel aboard the sunliner is sensible. Although Atomic gains her groovy augmented powers during the course of the book, at the start she's a normal human finding out more about the environment she's grown up in, easing the reader into this very strange world by using a character we can identify with.

And it is a very strange world indeed. As usual for highly advanced technological civilisations in contemporary science-fiction, everyone seems to be shagging everyone else out of general idleness. People make their fortunes speculating on the mineral content of passing asteroids. The youngest generation on board the ship obsesses about creating habitats that sound more like planetary theme parks.

Contrast is eventually provided as the sunliner detects signals from the planet 'Ground' - home to giant bat creatures that are just becoming industrialised. MacLeod's depiction of this quaint civilisation was the book's highlight to me. Where the sunliner reads as a bit of an Iain Banks rip-off in places, Ground has a fully fleshed society. The bats go to cute bars where they get drunk by biting into fermented fruits. They have universities but also mutilate their own kind for slave labour. They preen each other on romantic assignations but snap the wings off live prey animals so their young can feed more easily. And they have politicians and secret services, and a Cold War with another continent.

Frankly, it's just such a rich creation that I found myself wincing a bit every time the action switched back to the sunliner where everything's gosh-wow and conferences happen in seconds and everyone's telepathic.

Just before I sound as though I'm writing off the traditional science-fiction elements of the book, the one thing I really liked was a bit that stood out head and shoulders above everything else aboard the sunliner. Ground detects the arrival of the sunliner - realising it's a sign of intelligent life due to the fact they can tell it's decelerating as it approaches.

It's decelerating because the sunliner people have spent the last four hundred years piling all their rubbish in a huge mountain at the front of the ship - ready to pile it into the fusion reactor to act as reaction mass. It's a bit of solid, plausible science that advances the story, exactly what science-fiction should be about as far as I'm concerned.

Events in the novel reach a head as the sunliner's population becomes divided on what should be done about the planet - and most of the ethical dilemnas will be broadly familiar to anyone who's watched a bit of Star Trek.

These closing chapters are surprising, as a novel characterised by hand-wringing and inactivity draws to its close in a flurry of action, but it also feels right. The idea that there are events so important that we have to learn the world all over again is a simple one, but elegantly stated. No clues as to the book's ending from me though, read it yourselves!

This is a book for people who quite like science-fiction, but there's a lot of mileage there for less specialised readers, and there's a nicely philosophical heart to the whole thing. I bought it pretty soon after the paperback came out for about £8.00, but it's been out a couple of years now, so expect to be able to get it for less than a fiver from Amazon...