The last decade in space was marked by a blend of the tragic, the increasingly routine – namely a series of flights to the International Space Station – and some scientific triumphs.
For manned flight, the defining event was the loss in 2003 of the Shuttle Columbia with its seven crew members during re-entry into the atmosphere. The accident over Texas led to a two-year grounding of the US Shuttle fleet and hastened its eventual retirement; five final flights are scheduled for next year.
Meanwhile, the space station has been growing ever larger, as the Shuttle and Russian Soyuz rockets have transported numerous modules up to its orbit 340km above the Earth.
But the project has never caught the imagination of the public, whose taxes have contributed an estimated $100bn (€70bn, £62bn) to building the space station during the past 15 years. This is partly because the world’s space agencies have not made clear to people – or perhaps even to themselves – the point of the space station.
Is it there mainly as a symbol of permanent human presence in space, pointing to future manned missions to more exciting destinations such as Mars? Or is it a practical base for carrying out research in zero gravity above the Earth’s atmosphere? No one seems to know.
Prospects for manned spaceflight in the next decade are uncertain. As a successor to the Shuttle, Nasa, the US space agency, is developing the Constellation system, featuring a crew vessel called Orion and two Aries rockets.
But Constellation will not be ready for routine use for seven or eight years – and a commission advising President Barack Obama on the future of the US space
programme has expressed doubts about whether the country can afford Constellation in its present form. Mr Obama is expected to outline a new course for Nasa early next year.
Meanwhile, a new group of space powers is rising in the east. China has carried out three manned space missions and launched a moon probe. India’s lunar orbiter, Chandrayaan-1, played an important role in this year’s discovery of water on the moon.
Highlights of the decade’s space science, achieved with unmanned missions, include landings on Mars – the US rovers Spirit and Opportunity have been trundling over the red planet for more than five years – and on Saturn’s giant moon Titan by the European Huygens probe. And space telescopes have given spectacular views of the universe.
As for the next decade, the most exciting achievement of space science just might be the discovery of Earth-like planets capable of sustaining life in star systems light-years away.