The Future of Space: A Space Elevator by 2050?

space_elevatorIn the ongoing effort to ensure humanity has a future offworld, it seems that another major company has thrown its hat into the ring. This time, its the Japanese construction giant Obayashi that’s declared its interest in building a Space Elevator, a feat which it plans to have it up and running by the year 2050. If successful, it would make space travel easier and more accessible, and revolutionize the world economy.

This is just the latest proposal to build an elevator in the coming decades, using both existing and emerging technology. Obayashi’s plan calls for a tether that will reach 96,000 kilometers into space, with robotic cars powered by magnetic linear motors that will carry people and cargo to a newly-built space station. The estimated travel time will take 7 days, and will cost a fraction of what it currently takes to bring people to the ISS using rockets.

space_elevator_liftThe company said the fantasy can now become a reality because of the development of carbon nanotechnology. As Yoji Ishikawa, a research and development manager at Obayashi, explained:

The tensile strength is almost a hundred times stronger than steel cable so it’s possible. Right now we can’t make the cable long enough. We can only make 3-centimetre-long nanotubes but we need much more… we think by 2030 we’ll be able to do it.

Once considered the realm of science fiction, the concept is fast becoming a possibility. A major international study in 2012 concluded the space elevator was feasible, but best achieved with international co-operation. Since that time, Universities all over Japan have been working on the engineering problems, and every year they hold competitions to share their suggestions and learn from each other.

space_elevator3Experts have claimed the space elevator could signal the end of Earth-based rockets which are hugely expensive and dangerous. Compared to space shuttles, which cost about $22,000 per kilogram to take cargo into space, the Space Elevator can do it for around $200. It’s also believed that having one operational could help solve the world’s power problems by delivering huge amounts of solar power. It would also be a boon for space tourism.

Constructing the Space Elevator would allow small rockets to be housed and launched from stations in space without the need for massive amounts of fuel required to break the Earth’s gravitational pull. Obayashi is working on cars that will carry 30 people up the elevator, so it may not be too long before the Moon is the next must-see tourist destination. They are joined by a team at Kanagawa University that have been working on robotic cars or climbers.

graphene_ribbonsAnd one of the greatest issues – the development of a tether that can withstand the weight and tension of stresses of reaching into orbit – may be closer to being solved than previously thought. While the development of carbon nanotubes has certainly been a shot in the arm for those contemplating the space elevator’s tether, this material is not quite strong enough to do the job itself.

Luckily, a team working out of Penn State University have created something that just might. Led by chemistry professor John Badding, the team has created a “diamond nanothread” – a thread composed of carbon atoms that measures one-twenty-thousands the diameter of a single strand of human hair, and which may prove to be the strongest man-made material in the universe.

diamond_nanothreadAt the heart of the thread is a never-before-seen structure resembling the hexagonal rings of bonded carbon atoms that make up diamonds, the hardest known mineral in existence. That makes these nanothreads potentially stronger and more resilient than the most advanced carbon nanotubes, which are similar super-durable and super-light structures composed of rolled up, one atom-thick sheets of carbon called graphene.

Graphene and carbon nanotubes are already ushering in stunning advancements in the fields of electronics, energy storage and even medicine. This new discovery of diamond nanothreads, if they prove to be stronger than existing materials, could accelerate this process even further and revolutionize the development of electronics vehicles, batteries, touchscreens, solar cells, and nanocomposities.

space_elevator2But by far the most ambitious possibility offered is that of a durable cable that could send humans to space without the need of rockets. As John Badding said in a statement:

One of our wildest dreams for the nanomaterials we are developing is that they could be used to make the super-strong, lightweight cables that would make possible the construction of a ‘space elevator’ which so far has existed only as a science-fiction idea,

At this juncture, and given the immense cost and international commitment required to built it, 2050 seems like a reasonable estimate for creating a Space Elevator. However, other groups hope to see this goal become a reality sooner. The  International Academy of Astronautics (IAA) for example, thinks one could be built by 2035 using existing technology. And several assessments indicate that a Lunar Elevator would be far more feasible in the meantime.

Come what may, it is clear that the future of space exploration will require us to think bigger and bolder if we’re going to secure our future as a “space-faring” race. And be sure to check out these videos from Penn State and the Obayashi Corp:

John Badding and the Nanodiamond Thread:


Obayashi and the 2050 Space Elevator:


Sources:
cnet.com
, abc.net.au, science.psu.edu

News from Space: The Slingatron

slingatronPlacing things into orbit is something humanity has been doing since the 1940’s, beginning with Germany’s V2 Rockets, then giving way to artificial satellites like Sputnik in the 1950’s. These efforts really came into their own during the 1960’s and since, when manned missions reached high orbit and even the Moon. But despite all these  milestones, little has been done to address the problems of cost.

Ever since space travel began in earnest, the only way to send satellites, supplies and shuttle craft into orbit has been with rockets. Even at its cheapest, a space launch can still cost an estimated $2000 per pound per mission, due to the fact that the rockets employed are either destroyed or rendered unusable once they’ve completed their mission.

slingatron-20Attempts to create reusable launch systems, like the SpaceX Grasshopper, is one solution. But another involves “slinging” payloads into orbit, rather than launching them. That’s what HyperV Technologies Corp. of Chantilly, Virginia is hoping to achieve with their design for a “mechanical hypervelocity mass accelerator”, otherwise known as a “slingatron”.

Invented by Derek Tidman in the 1990s, the slingatron replaces rockets with a more sophisticated version of the sling. However, the principle differs somewhat in that the device uses something far more sophisticated than circumferential force. In the end, the name cyclotron might be more apt, which is a very simple particle accelerator.

 

slingatron-11Utilizing a vacuum tube and a series of magnetic/electostatic plates of opposing charges, an atomic particle (such as a proton) is introduced and sent back and forth as the polarity of the plates are flipped. As the frequency of the flipping is increased, the proton moved faster and faster in a series of spirals until it reaches the rim and shoots out a window at extremely high velocity.

The slingatron achieves the same result, but instead uses a spiral tube which gyrate on a series of flywheels along its length. As the slingatron gyrates, a projectile is introduced and the centripetal force pulls the projectile along. As the projectile slides through larger and larger turns of the spiral, the centripetal forces increase until the projectile shoots out the muzzle, traveling at several kilometers per second.

slingatron-13Ultimately, the goal here is to build a slingatron big enough to fire a projectile at velocities exceeding 7 km/s (25,000 km/h, 15,600 mph) to put it into orbit. With rapid turnarounds and thousands of launches per year while all of the launch system remains on Earth, the developers claim that the slingatron will offer lower costs for getting payloads into orbit.

However, there are weaknesses to this idea as well. For starters, any projectile going into space will also need to be fitted a small set of rockets for final orbit insertion and corrections. In addition, the G-forces involved in such launches would be tremendous – up to 60,000 times the force of gravity – which means it would be useless for sending up manned missions.

slingatron-15In the end, only the most solid state and hardened of satellites would have a chance of survival. The developers say that a larger slingatron would reduce the forces, but even with a reduction by a factor of 10,000, it would still be restricted to very robust cargoes. This makes it an attractive options for sending supplies into space, but not much else.

Still, given the costs associated with keeping the ISS supplied, and ensuring that future settlements in space have all the goods and equipment they need, a series of slingatrons may be a very viable solution in the not-to-distant future. Combined with concepts like the space penetrator, which fired bullet-like spaceships into space, the cost associated with space travel may be dropping substantially in coming decades.

All of this could add up to a great deal more space traffic coming to and from Earth in the not-too-distant future as well. I hope we have the foresight to construct some “space lanes” and keep them open! And in the meantime, enjoy this video interview of Dr. F. Douglas Witherspoon explaining the concept of the slingatron:

Source: gizmag.com