Seriously, George Osborne is investing in a spaceship!

It's a cliché to talk about August in politics being the "silly season" (not only is it almost over but surely Syria makes it fairly serious) so instead I thought I'd talk about something that's awesome.

One of the interesting things to come out of the Budget back in March was that the government is planning to invest £60m in a company called Reaction Engines who are developing the SABRE engine which could make spaceplanes a reality.




This is really exciting because for those of us who believe that the long term future of our species requires that we spread beyond this increasingly small planet the decades since the moon landings have been a bit of an anticlimax.

This chart by xkcd is pretty depressing but the basic reason why we never got beyond 11 people walking on the moon between 1969 and 1972 is that it's ruinously, hideously, astonishingly expensive to leave the earth's atmosphere. Back when the space shuttle was running, it cost something like £15,000 per kilogram to put a payload into space. Commercial satellites (one of the few examples of the direct commercial benefit of putting things into space) are launched on cheaper rockets but these are still hugely expensive because space-rockets are basically like disposable cameras: single use and then you throw them away.

Even the space shuttle, despite supposedly being reusable, needed a new set of huge booster rockets and a new giant fuel tank for each trip. Launching it required months, if not years, of preparation time making it really reusable in name only.

That's why Skylon is so exciting. Skylon is the spaceplane idea that Reaction Engines are proposing to build using the SABRE engines mentioned above. There's quite a good explanation of it here and here but the basic gist is that it takes off like a plane, rises to a high altitude then fires rocket engines to take it out of the atmosphere. When it's ready to come down, it lands like a normal plane as the space shuttle does. Unlike the space shuttle, however, it's fully reusable (Alan Bond of Reaction Engines talks about 48 hours between a Skylon plane landing and taking off again on the next flight) and much, much cheaper to put a payload into space. Skylon would reduce the cost per kilogram from the £15,000 mentioned earlier to around £650 or by around 95%.

And the consequences of this are potentially enormous because suddenly putting things into space and bringing them back down again are cheap enough to be accessible to more than just governments and huge corporations and fast enough to make large scale projects realistic.

Which means that loads of things which are possible but dismissed as too expensive are now feasible because we can cheaply put things into space and bring them down again. Mining asteroids for resources, establishing a permanent base on the moon, certainly building another space station would be infinitely cheaper than the $100 billion or so than the ISS cost to assemble (this is a guess, I'm open to fact checking but the point stands - it's a lot of money) as well as being quicker to build (the ISS is as yet unfinished).

Going to Mars is much more realistic because we can assemble a larger craft in space from components built on earth.

As well as this, the much faster turnaround time between flights makes space travel far more flexible. Is one of Sky's satellites malfunctioning? Now you can have a repair crew in orbit by the end of the week.

Barack Obama took a lot of criticism when he axed the Bush-era Constellation programme for returning astronauts to the moon as a base for a Mars-shot (particularly from fellow Star Trek fans accusing him of betraying the cause) but he also did something much more far reaching: opening up space flight to the private sector.

Instead of NASA spending millions of taxpayers dollars assembling a mission for each re-supply flight to the ISS, they're now contracting out to private companies, the most prominent being Elon Muck's SpaceX who are experimenting with reusable rockets where the various stages land softly instead of burning up after being ejected from the main payload.

The Guardian's Science Weekly podcast mentioned that this was like the early days of human flight with dozens of entrepreneurial (though obviously extremely wealthy) people experimenting with different innovations and methods. Skylon is exciting because it lowers the barriers to entry for this competition and the more companies that take part, the more likely we are to see real technological progress in this area.

 The fact that private companies are taking the burden of innovation also solves the other big problem with space flight which is that whenever you ask somebody whether we should be trying to go to the moon or Mars, the reply is a variation of "I think we have enough problems down here to deal with first...". Space flight is seen as a luxury, an optional extra particularly at a time when governments are facing ever-increasing demands on their resources. It's a perfectly understandable statement when government money is on the line so the best thing about private spaceflight is that it's about someone else's money, not the taxpayer. That means (for the public) that the cost of failure is low and therefore there's more room for experimentation and innovation.

If and when we go to Mars it'll be with privately constructed vehicles probably built to meet a government contract.

So for those of us (like myself) who grew up watching repeats of Star Trek then looking with dismay at how far humanity still had to go the next 20 years could be a pretty exciting time. Especially because if Skylon takes off (both literally and figuratively) then space tourism could get a lot cheaper than the $250,000 Virgin currently charge to go near to space without actually getting there.