The last 12 months have certainly been an eventful year in space.

Despite protests from Russian scientists, the space station Mir finally dropped out of orbit and burned up in the Earth's atmosphere after 15 years aloft.

In March, the Russian space agency set the 140-tonne Mir space station on a downward course for the Earth. What didn't vaporise in the atmosphere fell in fragments into the Pacific Ocean.

Farewell to Mir as it burns up over the Pacific

Although it suffered a few serious accidents in its later years, Mir was a success story - outliving its planned life by 10 years.

Former Russian space agency head Roald Sagdeev outlined why the Mir project was so important.

"Fifteen years in space, the ability of man to eliminate problems, to repair, to dock new modules, to bring new hardware inside the station and outside in the vacuum of space - this is very important experience and knowledge and I think the International Space Station (ISS) will be the first beneficiary of this experience."

At the ISS, several visiting crews of mainly Americans and Russians put some of that valuable knowledge into practice.

£20m ticket

Spacewalkers fitted a new habitation module and a new airlock. The station is now double the size it was when the first crew took residence more than a year ago - though it is still a long way from the football-pitch-sized vessel first envisaged.

However, the spirit of international harmony surrounding the station received something of a setback in May, with the arrival and departure of the world's first space tourist.

Businessman Dennis Tito was happy and so was the Russian space agency who received $20m for taking Mr Tito to and from the orbiting station.

The American agency Nasa was not happy, protesting that a tourist on board was a potential danger.

Dennis Tito: Pursued his dream to go into space

But Dennis Tito's dream came true and he could not resist a jibe at Nasa.

"Bureaucracies don't like to change, and this clearly forced a change," he said. "And it's going to have its impact."

The Russians are planning to take a second tourist up to the station next April but, more significantly, a committee of experts took a hard look at Nasa's management of ISS programme for President Bush - and did not like what it discovered.

Costs rocketing

Dr Chris Welch, a space researcher at the UK's Kingston University, said: "What they have found is that, although there isn't a problem with the space station itself - it's technically well founded - Nasa seems to lack the ability to manage projects to cost and schedule.

"Certainly, the costs just seem to be drifting up and upwards and at the moment, no-one at Nasa seems to be able to get a firm grip on this."

If we can't manage to organise and run a project in Earth orbit, what are our chances of doing it on the way to Mars and back?

Chris Welch, space researcher

Back in 1993, the agency predicted it would be spending $17bn to complete the station. The estimate now stands at about $30bn and the Bush administration is determined to stop the costs rising.

To that end, the president appointed new head administrator Sean O'Keefe - a man whose background is finance, not science and technology.

Mr O'Keefe proposed a radical downsizing of the station's scale - fewer modules to be built and fitted, no purpose-built escape pod and an intended crew of seven people cut to just three.

So what now of the once-promised giant space laboratory and the valuable new insights into medicine, new materials and drugs? According to Peter De Selding, of the journal SpaceNews, those dreams are going to be very hard to deliver.

Space discord

"You need two and a half people full time to just operate the station. These people aren't doing any research. That one half of a person's time can be devoted to some research but it's not at all what anyone had expected when the station was designed for a seven person crew."

On the other hand, many scientists think the research potential of the station was hugely oversold anyway and will be delighted if the station is cut down to size.

The proposed downsizing has upset Nasa's smaller partners on the programme - such as the Canadian and European space agencies.

They have already spent money preparing projects that now may be axed. Chris Welch believes this does not bode well for the other justification for the space station's existence - the first step from which humanity voyages to other planets.

"The future in space is international. If you're talking about missions to Mars or anything ambitious like that, it's so expensive that it's very doubtful that any one country will do it. So if we can't manage to organise and run a project in Earth orbit, what are our chances of doing it on the way to Mars and back?"