I’ve flown to Sydney and back since my last post. After staring through the window of a Boeing 737 at ten thousand metres, up where the atmosphere itself is tenuous and the Earth is curved beneath me, it’s no wonder my thoughts have turned to space travel…
The last few weeks have seen two announcements concerning the exploration of space. Although the announcements were made separately, the timing could not have been more perfect – they demonstrate an interconnected vision for the future of spaceflight.
The first announcement was NASA’s selection of commercial partners for crew transport to the International Space Station. io9 has a fairly comprehensive article about the situation here.
The emphasis of the announcement is not on technology, but politics. The US currently relies on Russia’s Soyuz capsules to transport crew to the International Space Station. When Russia announced on 8 September that part of the training was now being moved to Crimea, this put American astronauts into an awkward political situation. If they travelled to Crimea without getting a Ukrainian visa, they would be acknowledging that the region belongs to Russia. But if they didn’t attend training, they would not be allowed to travel to the station.
NASA was quick to recover, announcing that they had selected Boeing and SpaceX to transport crew up to the ISS, with trips starting in 2017.
Allowing commercial partners to take over the role of crew transportation means that space is opening up to industry. SpaceX is significantly ahead of Boeing in this aspect, having already designed a functional return vehicle, the Dragon v1. Boeing’s Cygnus vehicle, which currently does cargo supply runs to the ISS, is designed to burn up on re-entry. So it’s probably not the vehicle of choice for astronauts.
Even more importantly, the outsourcing of crew transportation allows NASA to redirect some of its budget to its proposed Mars mission and other endeavours.
The second announcement was that Japanese construction company Obayashi plans to build a space elevator by 2050.
The space elevator is a concept that I have long supported – it’s one of those crazy ideas that seemed like science fiction fifty years ago, yet continues to become increasingly achievable.
Space elevators require an inversion in the way we think about constructing things. Instead of building upwards into space, a tether would be lowered down to the Earth from geosynchronous orbit (36,000 km). Simultaneously, a counter-weight would be extended in the opposite direction. The centrifugal force of the Earth’s rotation would fling that counter-weight outwards – the entire structure is supported by the tension. The tensile strength of the material is the key to the operation; it needs to be strong, yet light and flexible. Obayashi believe that advances in carbon nanotubes mean that the construction of a cable may be possible as soon as 2030.
The benefits of a space elevator would be numerous. It currently costs approximately $22,000 per kilogram to take cargo into space. Riding on the elevator, it would only cost $200. With numerous cars running up and down the cable, space tourism could help fund the cost. Rockets could be assembled in orbit, without the vast fuel reserves needed to escape from Earth’s gravity. And the elevator itself could be used as a centrifugal slingshot to launch payloads to other planets.
Whether Obayashi succeed in their endeavor is the subject of speculation. At the very least, more research into the practicalities of space elevators would help solve some of the technical aspects of their design. It’s something that I can get excited about – previous proposals have indicated that the Indian Ocean off the coast of Perth would be an ideal location for a floating base station. Practically in my back yard!
Taken together, these two announcements reflect a positive step in the future of spaceflight. It’s a positivity that’s been lacking since the space shuttle program was discontinued in 2011.
That’s all for today. Don’t forget to look out for the total lunar eclipse on Wednesday night!