Wednesday, July 2, 2014

A Future Journey To High Heavens - A Vision Of Tomorrow's Reality

Once upon a time, the biblical patriarch Jacob had a dream of a ladder leading to heaven, and angels ascending and descending on it.

Counterweight spaceport.
Credits: Obayashi Corp.
We, modern human, also have a dream to come closer to high heavens and the idea of a space elevator is not a new one. Already, in 1895, a Russian called Konstantin Tsiolkovsky (1857 – 1935), Russian rocket scientists and a true visionary and pioneer of astronautics proposed a free-standing “Tsiolkovsky” tower that would stretch from the Earth’s surface to a ‘counterweight’ somewhere in geostationary orbit.

Later many others came up with ideas.

By 2050, however, fast developing technologies are able to deliver genetically-modified spider silk. With this material, it could be possible to construct a super strong cable.

In their paper "Levitation characteristics of a high-temperature superconducting Maglev system for launching space vehicles", the Chinese scientists of School of Astronautics, Beijing University of Aeronautics and Astronautics, also propose a solution based on Maglev system for launching space vehicles. It is an effective method to reduce the cost of space launch.

Significant reduction in the launch cost is a precondition for the expansion of commercial activities into space, the scientists say. Maglev (magnetic levitation) is a method of using the forces produced from either electromagnets or permanent magnets to suspend, support, guide, separate and/or propel objects.

The idea of an elevator into space has been around
for some decades. The Startram orbital launch system
would transport passengers and cargo into space
in a magnetic levitation (maglev) train
"Maglev launch assist vehicle (Maglifter)," we read in the paper, "has been proposed to provide a high ground takeoff velocity (up to 1000 km/h), which is expected to cut down the propellant consumption and the structure mass for space vehicles."
"On the other hand, Maglev technology has made great progress since the 1920s. The ground velocity of the Maglev train has attained 550 km/h, which provides feasibility for the achievement of Maglifter. However, during the Maglev launch assist, the Maglifter will endure complicated aerodynamic effects, such as aerodynamic forces and moments, which will cause some problems on the Maglev system...". Just until recently, Scientists at Southwest Jiaotong University in China have reportedly built a maglev train that could reach 1,800 mph (2,900 km/h). According to The Daily Mail, a vacuum is used to minimize air resistance. Project lead Dr Deng Zigang claims it could be used for military or space launch systems.

Maglev trains use electromagnetism to lift the train off a track and to provide propulsion. By removing the need for contact with a surface via wheels, friction is substantially reduced and speed can be increased. They are also smoother to ride than surface-supported alternatives and are less affected by the weather.

The current fastest passenger-carrying maglev train can travel at up to 268 mph (431 km/h) and once reached 311 mph (501 km/h) in pre-launch tests. The Shanghai Maglev Train opened in April 2004 and runs 18.95 miles (30.5 km) from the center of the Pudong district of Shanghai to Shanghai Pudong International Airport.

At those sort of speeds, air resistance becomes a serious issue. The Mail article cites a paper by Zigang in which he writes, "If the running speed exceeds 400 kilometers (250 miles) per hour, more than 83 percent of traction energy will wastefully dissipate in air resistance."
The idea of running a maglev train in a vacuum, therefore, seems a logical one. It would increase its potential top speed and improve its energy efficiency. This principle is the same as the one that the Evacuated Tube Transport is based, which could theoretically transport people between new York and Beijing in 2 hours.
Elon Musk's proposed Hyperloop, meanwhile, isn't thought to use a vacuum to reduce air resistance, but will still potentially max out at 760 mph (1,220 km/h). Zigang's concept would leave even that in its dust.

In developing the train, Zigang first had to create a small, remote-controlled ring-line version of the system on which the maglev vehicle could accelerate to 15 mph (25 km/h). That was achieved in February last year, after which an evacuation tube was added to create an internal vacuum.
With the vacuum created, the vehicle was reportedly able to accelerate to a maximum speed of 30 mph (50 km/h). The prototype was, of course, run without passenger and was limited by the small 6 m (20 ft) radius of the ring guideway.
"The meaning of the project is that it will be the first one to realize the prototype of the future evacuation tube transportation," The Daily Mailreports Zigang as saying. "At this moment, we are conducting evacuation tests on the new system. We will release our achievements after the successful running in the near future."

What seems impossible and laughable today may seem surprisingly doable tomorrow.

Arthur C. Clarke was once asked when a futuristic space elevator would become a reality and he gave probably the best answer: "Probably about 50 years after everybody quits laughing".

It means that visions could turn science fiction into reality but this vision costs... because traveling to space is not cheap under current ponzi scheme fiat currency system, but feasible under International fixed exchange rates interest free public credit system.

A zero-gravity spaceport is the only solution to start-jump interplanetary exploration starting with the moon resources extraction and use it to mine other planets.