Cheap tickets to space :)

There are many reasons why exploring and subsequently living in place will be costly.

However, possibly the greatest obstruction which needs to be surmount for the doorway to be opened so that mankind can freely move from the ground will be the fact that here on our planet we survive at the side of a seriousness easily; each kilogram of textile going into orbit must be hauled upward out of the ground’s gravitational force.

Currently, the price-to-orbit starts at around US$19,000 per kilogram – and that’s for inanimate people - the price for lifting humans to orbit is often high payable to the fact that we expect atmosphere, nutrient, water and a controlled surroundings, all of which need to move with us; the overall cost will require to include education, ground backing crowd, ground based recuperation teams and base.

At every place launching a really big sum of the people that is lifted into ground orbit comprises of the fuel needed by projectile engines. Are there any new methods of moving textile off the surface of the earth? What can be done to lower the costs of flinging mass into earth orbit?

One alternative is the concept of a ‘space elevator’.
space elevator

The basic idea is a structure of some kind that reaches from the surface of the earth into space. Getting to – or from – earth orbit will be achieved by travelling up and down the structure. At this date, it’s difficult to imagine construction materials that would allow for the erecting of what most of us would imagine as a traditional ‘building’ – bricks or some other material compressing themselves down to the ground and thereby maintaining overall structural integrity. It is extremely unlikely that the construction of such a tower will ever be achieved that will raise a mass to geostationary orbit – 35,786 km. A slightly more realistic solution involves the production of a long, strong cable, extending at least to geosynchronous orbit where it might be tethered to a counterweight such as a space station or captured asteroid. Material can then be ferried to and from orbit by riding down the tether.

Once the space elevator has been constructed, the theoretical cost for moving mass to orbit dramatically decreases – by some conservative estimates to as little as US$ 500 per kilogram – and by other estimates, far less.

Still, the question remains; what material will the tether need to be made of in order to have the necessary tensile strength for a project of this magnitude? The emerging capabilities of nano-technology hint at a possibility in the form of carbon nanotubes. Structurally, these nanotubes are composed of graphite; a carbon atom bonded to three other carbon atoms, these then form very strong hexagonal sheets, and in turn these sheets are rolled into a small seamless cylinder with a diameter of a nanometre – one billionth of a metre. Carbon nanotubes have been produced which have a tensile strength of over 50 times that of high-carbon steel.

There are other problems to be considered in the construction and maintenance of a space elevator. At the level of the earth for example; how to deal with the effects on the tether of poor weather within the earth’s atmosphere, lightning, fierce storms and so on. Or the risk of disaster due to the severing of the cable due to accident or deliberate sabotage. carbon nanotube As the cable crosses out of the realm of the earth’s influence other problems arise; such as leaving the earth’s protective magnetic field and the subsequent effects of solar radiation on unprotected passengers travelling in a relatively slow elevator – or the corrosive effect that the same radiation will have on the elevator cable. Perhaps the greatest concern will be that of orbital debris and collisions. A small particle of dust, or worse, metal, travelling in the opposite direction as the space elevator’s cable could have a relative closing velocity of more than 20km / second – or 72,000 km/ hour. An impact with a large object would most likely result in a complete loss of the space elevator. However, to clear the way for the elevator cable, in theory, some sort of garbage collection is possible as since the dawn of the space age US Government agencies have been tracking pieces of orbital debris, some no larger than a paint chip.

If it is to be done, the accomplishment of a space elevator will only be achieved by the dedication and commitment of scientific researchers who will expand our knowledge of the natural universe and technological innovators who will develop new materials, production techniques, control and automation systems. At one point within the 20th century, it was widely believed by extremely learned and reputable people that travel by ‘heavier-than-air’ machines was impossible.