The launch of a Chinese astronaut marks a new chapter in manned space exploration and it is full of uncertainties and possibilities.
By Dr David Whitehouse
BBC News Online science editor
With this mission, China has made a bold move and expressed its space intentions at a time when the US space effort has major problems, and the Russian programme is in decline.
Will China launch guest astronauts?
So although Yang Liwei is only the 431st person to go into space, his flight looks forward to a new future.
By the time China hosts the Olympics in 2008, it may have a small man-tended space station in orbit, with live greetings from orbit to the competitors.
How China's image is about to change.
Its Shenzhou capsule, although based on the tried and tested Russian Soyuz spacecraft, is more advanced. China has learnt from the spaceflight experience of others, and technology has improved in the past 40 years.
This means that Shenzhou is far more capable than the craft that first took Americans and Russians into space - the Mercury and Vostok capsules.
The first man in space - Yuri Gagarin - spent one hour and 48 minutes aloft. The first American in space - Alan Shepard - spent just 15 minutes above the Earth. Yang Liwei will spend 22 hours.
Although Soyuz is a highly capable space vehicle, it is operated by a declining space power which can barely afford to keep the vehicle operating to and from the International Space Station (ISS).
In the present situation, one cannot conceive of Russia building a space station like Mir - which it let crash to Earth for want of money - for a long time.
Better and better
Shenzhou is certainly not the US space shuttle, but that is a project with its own problems.
The shuttle fleet is grounded, possibly until late next year, and the US space agency (Nasa) is trying to revitalise its efforts to build a shuttle successor.
One of the spacecraft that Nasa will develop will probably be smaller and less sophisticated than the shuttle, to be used as a ferry craft for the ISS.
Up and away to a new future
Shenzhou will then compare favourably with it. With time, China's achievement will look better and better.
China's plans to assemble modules in space, to make man-tended platforms, will also take the emphasis away from the US and Russia - especially Russia.
Yang Liwei flew solo, the first solo space mission since the Soviet Soyuz 4 in 1969, but we know Shenzhou can carry three passengers.
What is next?
In the future, it is not unreasonable to think that China could fly guest astronauts like the Soviets did in the past, or even paying customers as the Russians have recently done.
It has been said that the US would never allow Shenzhou to dock with the ISS. There are orbital difficulties precluding a link-up at present but they could be overcome and Shenzhou has a compatible docking system.
Also, given what happened to Columbia, perhaps it is time for the three space faring nations to develop a mutual aid policy should there be a space emergency.
Some media outlets have reported that China may launch a manned mission to the Moon.
This is far-fetched, at least for the next decade, but beyond that, after 10 years of Shenzhou operations and experience, who knows?
So Yang Liwei goes into the history books, and the future of manned spaceflight has new possibilities.