As China prepared to launch its first manned space flight, Vietnam's Pham Tuan - who became the first Asian space traveller aboard a Soviet Union Soyuz in 1980 - spoke to the BBC's Vietnamese Service.
When I experienced zero-gravity for the first time in space, I was taken aback.
Flying a spacecraft is different from all other modes of flying, because you can't take a spacecraft into orbit for training as you do with aeroplanes in the sky.
When you learn to fly in a plane, you have an instructor sitting next to you until you are confident - cosmonauts don't get this kind of training. So, everything was strange from the moment we took off to the moment we landed.
Pham Tuan said he felt overwhelmed
We cosmonauts are generally pilots who are already familiar with observing the Earth from the sky, but gazing at it from space is an overwhelming feeling. Even more so when you are weightless and disoriented.
The Earth seemed very distant indeed. It looked completely different from how it looks when viewed from the moon or from an aeroplane.
The first time I saw the Earth from space was a very difficult moment to describe - it was night when I first saw it. Then, gradually, sun-rise came and the image was familiar, having seen so many pictures of the Earth taken from space before. But still it's difficult to describe when you see it for yourself.
VIETNAM'S SPACE HERO
Born 14 February 1947
Just one flight - 7.86 days - in 1980
Also famed as first fighter pilot to shoot down a US B52 during Vietnam War
Of course, for one's relatives, it's like a family having someone going to war. They were even more nervous then me, waiting anxiously to be updated about my well-being.
As for China's launch, they have been preparing for that for a very long time now.
Even in the early 1990s, they announced that they would launch the shuttle. This is an extraordinary achievement by China in aerospace.
At the same time, our [space programme] hasn't made progress. When the Soviet Union collapsed, we lost a partner and it was a difficult situation.
But now we're preparing to launch a satellite, and hopefully from programmes like this, we can make further progress.
Apart from Russia we can still co-operate with other countries in terms of research, on condition that our own economy continues to grow... However, due to the historical co-operation and relationship between the two countries, Russia would be the best choice
China has a very independent stance; they tend to do it alone.