Space Elevators: New Era of Transportation to Space!

Space Elevators:

These could transport people and cargo to and from orbit without using a rocket, as over 50 years Rockets has been an only technology used to allow things and people escape from the earth's surface. Idea of space elevators came into existence in 1895 when Russian Space Scientist, Konstantin Tsiolkovsky proposed a way of getting into space by building a tower to reach up.

By then many scientists and science fiction has also developed the space elevator concept and working on this project to make this planetary trip more efficient and useful to humankind.

How does Space Elevators work:

• A space elevator is a proposed type of planet to space transportation system.
• The main component would be a cable anchored to the surface and extending into space. The design would permit vehicles to travel along the cable from a planetary surface, such as the Earth's, directly into space or orbit, without using large rockets.
• An Earth-based space elevator would consist of a cable with one end attached to the surface near the equator and the other end in space beyond geostationary orbit. 

Structure of a Space Elevator:

There are many space elevators design proposed for many planetary bodies and but they all have a common structure which consists of:

• Cable or Tether: A space Elevator cable is to be stretched from the base station at the equator to up an orbital platform and it would need to carry it own weight plus the additional weights of the carriage or climbers. Hence the required strength will vary along its length as at various points it would have to carry the weight of the cable below, or provide a downward force to retain the cable and counterweight above. The proposed length of the cable is 90,000 Km.
• Base Station: In case of Space Elevators a base station or anchor which will be fixed at one point on earth can be at equator
• Counterweight: A counterweight at the upper end keeps the center of mass well above geostationary orbit level. This produces enough upward centrifugal force from Earth's rotation to fully counter the downward gravity, keeping the cable upright and taut.
• Climbers: A space elevator cannot be an elevator in the typical sense (with moving cables) due to the need for the cable to be significantly wider at the center than at the tips. Climbers would need to be paced at optimal timings so as to minimize cable stress and oscillations and to maximize throughput. Lighter climbers could be sent up more often, with several going up at the same time.

Challenges to overcome :

• Manufacturing a space elevator cable which will not Collapse due to it's own weight currently scientists are working on carbon nano tubes as they are a theoretical possibility. 
• Space Elevator will also has to be corrosion resistant and should be capable of withstanding the extreme cold of upper atmosphere.
• Constructing a suitable counterweight is another challenge if we build it by taking the materials from earth 
  • a heavy, captured asteroid 
  • a space dock, space station or space port positioned past geostationary orbit
  • a further upward extension of the cable itself so that the net upward pull would be the same as an equivalent counterweight.

Benefits of a space Elevator:

Building a space elevator is challenging and is clearly very hard but was too placing a human being on moon 50 years back! So if we build a space elevator it would be very useful to humankind and one of the most significant space technology:

• With development of Space Elevators the access to space will be greatly improved.
• It can also allow the construction of solar power satellites that could beam energy to the ground.
• It can also allow human civilization to obtain new supplies of  raw materials by mining the asteroids on the moon as the resources on earth are finite and not going to last forever.
• Transporting people and cargo in space will be easy and affordable.

It may see hypothetical but constructing a Space Elevator may prove to be a critical stepping stone for a long term survival and evolution of all the species.

Somewhere something incredible is waiting to be known..

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