OrbitalHub

When I read The Fountains of Paradise a few years ago, I thought the space elevator was an interesting concept but that there was little chance of seeing it materialize like we saw the geostationary satellites become a reality after being depicted in a science fiction story by the same author, Arthur C. Clarke. And not just because some famous scientist said so, but because anchoring to the Earth a geostationary satellite with a cable measuring some 100,000 km is quite a technological challenge.

The first scientist to propose building a structure to reach space was Konstantin Tsiolkovski, who envisioned an orbital tower in 1895. In 1960, another Russian scientist, Yuri Artsutanov, developed this concept into an article called Into Space with the Help of an Electric Locomotive, which was published in Komsomolskaya Pravda. Artsutanov proposed linking of geosynchronous satellites to the ground using cables. It is interesting to mention here that Arthur C. Clarke and Yuri Artsutanov actually met years after the Fountains of Paradise was published.

Ok, so it is just science fiction, you might say. Well, not quite. There was a study ordered by NASA under the NASA Institute for Advanced Concepts (NIAC) program, which had as its object the investigation of all aspects of the construction and operation of a space elevator. The study was funded by NASA for more than two years and it was titled The Space Elevator.

A book was also published by the authors of the study, Bradley C. Edwards and Eric A. Westling. The book has the same title as the study. I found the book easy to read and really entertaining. Even if it becomes very technical in some parts, it is accessible to readers who do not have a technical background.

The book starts by presenting the main components of the design (the ribbon, the spacecraft, the climber, and the anchor), and the challenges that the space and the Earth’s atmosphere pose to the space elevator during the deployment phase and during the normal life of the program: lightings, meteors, and LEO objects, just to mention a few.

Being a feasibility study, the economic considerations had to be part of it. There are budget estimates that would draw the attention of potential investors, and even a realistic schedule for the development of not just one, but up to four ribbons.

While the space elevator is obviously a very cheap solution for deploying payloads in Earth’s orbit, it can also be used for opening Mars to human exploration and colonization. An Earth space elevator uploading materials in orbit working together with a space elevator downloading them on Mars would make possible the continuous flow of materials and colonists.

The later chapters of the book present the possible implications of the space elevator on the development of space travel and on the future of our technological society.

As the authors acknowledge, the book is not an exhaustive study of all aspects to be considered in the designing and building of the space elevator, but a good beginning. The proposed budget of 6 to 10 billion dollars for the project is not excessive considering the potential return of investment and that access to space is essential for the future development of our society.

Published in 2003, the book is a classic. I strongly recommend it.

In a follow up to The Space Elevator, Bradley C. Edwards and Philip Ragan wrote Leaving the Planet by Space Elevator, which was published in 2006.

For more information about the space elevator, including the 2008 Space Elevator Challenge and the Elevator: 2010 challenge, check out The Spaceward Foundation’s site.

Credits: NASA

Constellation Program is NASA’s new generation space transportation system. It is designed to cover a wide range of space missions, such as delivering supplies and human crews to the International Space Station (ISS) and traveling beyond low Earth orbit (LEO). The goal of the program is to establish a permanent human presence on the Moon and then go to Mars and other destinations.

The Constellation Program promotes exploration, science, commerce, and the United States’ presence in space.

Constellation consists of two launching vehicles (Ares I and Ares V), the Orion spacecraft, the Earth Departure Stage, and the Altair, which is the Lunar Surface Access Module.

Credits: NASA

Ares I is the crew launch vehicle that will be used to deliver the Orion spacecraft to LEO. Ares I is a two stage rocket, 94 m long and 5.5 m in diameter that can deliver a 25,000 kg payload to LEO.

The first stage is a solid rocket booster that evolved from the Space Shuttle Solid Rocket Booster (SRB). An additional fifth segment was added to the initial SRB design, which enables the rocket to produce more thrust and burn longer. The second stage uses liquid oxygen and liquid hydrogen as fuel. The J-2X engine used by the second stage evolved from the J-2 engine used on the Saturn V rocket.

In addition to its primary mission, Ares I can also be used to deliver resources and supplies to the ISS or to park payloads in orbit for retrieval by other spacecraft bound for the Moon or other destinations.

Credits: NASA

Ares V is the cargo launch vehicle of the Constellation Program. Ares V is a two stage rocket, 116 m long and 10 m in diameter. It will be able to deliver a staggering 188,000 kg (188 metric tonnes!) payload into a LEO.

The first stage uses both solid and liquid propulsion (two SRB-derived boosters and 6 RS-68 liquid fueled engines) while the second stage (the Earth Departure Stage) uses a single J-2X engine. It is a versatile launch system and it will be used to carry to LEO cargo and the components needed to go to the Moon and later to Mars.

Both launch vehicles are subject to configuration changes. The images reflect the configuration as of September 2006.

Credits: NASA

Orion is able to carry four to six astronauts. It will provide logistic support to ISS in the first stage. After that, Orion will become an important part of NASA’s human missions to the Moon and Mars.

The conceptual design is similar to the Apollo, but has been improved: an updated digital control system, automated pilot for docking procedures, and a nitrogen/oxygen mixed atmosphere.

The conical form is the safest and most reliable design for re-entering the Earth’s atmosphere. The landing procedure has also been modified: instead of a splash in the Ocean, the module will land on solid ground using a combination of parachutes and airbags.

Credits: NASA

Altair is the lander spacecraft component of the Constellation Program. Like its predecessor, the Apollo Lunar Module, Altair has two stages.

Altair will land all crew members of the lunar mission on the surface of the Moon, while Orion will stay in lunar orbit until the mission ends. The ascending stage brings the crew back on Orion for the journey home.