The launch in mid-July of the first inflatable space habitat marked another milestone in the commercialization of space, and a step closer to the dream of a space hotel to be realized next decade. This article will review the origins and development of the first space habitat, as well as plans for the first inflatable space hotel.
Since the start of the Apollo space program and the first moon landing in the 1960's, man has been intrigued by the possibility of space tourism where a room in space could be booked as conveniently and cheaply as one on Earth. But this scenario may no longer be purely science fiction. Approaching half a century since Soviet cosmonaut Yuri Gagarin, the first man in space, reached orbit, man is beginning to commercialize the final frontier. Amateur astronauts have taken part in official missions on several occasions since the mid 1980's. Since the first space tourist, American multimillionaire Dennis Tito, paid in excess of $20 million for the opportunity to undergo extensive training and spend a week on the multi-billion dollar International Space Station (ISS) in 2001, three others like him - South African Mark Shuttleworth and American Gregory Olsen. The first woman space tourist, Iranian-born American Anousheh Ansari - have followed.
Until recently, the only way to reach orbit was either the space shuttle or the Soyuz space capsule. In 2004, Scaled Composites launched the first non-government-sponsored manned spacecraft, SpaceShipOne. Though the vehicle attained only sub-orbital flight, it opened the door to a new generation of privately-funded spaceflights. Virgin Galactic is planning to launch SpaceShipTwo, capable of carrying passengers into sub-orbital altitude in late 2008, followed by a larger version capable of real orbital reach a few years later.
Scoring a parking spot for your private spaceplane in orbit is a different story. The ISS, which is still unfinished (mainly due to the Columbia disaster), is not a space hotel and, although occasional tourists have boarded the Russian part of the station, it is first and foremost a scientific laboratory that will not be used to accommodate a large number of space tourists. Seeking to launch a genuine space hotel, hotelier Robert T. Bigelow created the space tourism company, Bigelow Aerospace, in 1999. Following seven years of development, Bigelow Aerospace launched its first inflatable space structure, Genesis I, on July 12th, 2006 using a Dnepr LV missile (a converted Russian SS-18 Inter-Continental Ballistic Missile) from the Yasny Launch Base in Russia. Measuring 4.4 m (~14 ft.) in length and 1.6 m (~5 ft.) in diameter when compressed, the spacecraft successfully reached a 483 km (300 mi.) orbit, then extended its solar panels, and inflated in fifteen minutes, expanding its width to a full 2.54 m (~8 ft.) in diameter. The Genesis I prototype habitat will be followed in a few months by Genesis II, a more sophisticated habitat that will carry more cameras (18 as opposed to Gensis I's 13). The next stage will be the larger Galaxy-class of habitats with a volume of 23 cubic meters, double that of the Genesis-class. The final ambitious step will take place in about six years with the launch of the huge 330 cubic meter Nautilus habitat, approaching the ISS's 425 cubic meters of usable volume. Launching this enormous 25 ton structure into orbit is a daunting task and Bigelow Aerospace plans to use a larger booster such as the SpaceX's planned Falcon 9S rocket to launch it into Low Earth Orbit (LEO).
TransHab test at NASA (Credit: NASA)
The birth of Bigelow Aerospace and its inflatable space hotel concept in 1999 was intimately connected to the conceptualization and development of a space habitat for the planed future manned Mars Mission. The so-called TransHab project was initiated around 1997 by a NASA team headed by William Schneider, a prominent NASA engineer,monster beats. The 600 cubic meters required for the habitat would be too heavy and large to be lifted into orbit. Thus, Schneider and his team of engineers devised a light, inflatable module that could be loaded onto a rocket or the space shuttle, squeezed to about a third of its normal size, and inflated to its full size once in orbit. The TransHab concept was also suggested as a possible living quarters module for the ISS and, though finally cancelled by Congress in 2000, it became the basis of the Genesis-class space module.
TransHab in NASA's test facility (Credit: NASA)
One of the most important design features of the TransHab is its multi-layer (nearly two dozen), foot-thick, inflatable shell made of various extremely high-strength, lightweight fibers with numerous protective features. The outer layers of the shell break up space debris and micro-meteorites that may hit the shell with speeds of up to 7 km/s (about seven-times that of a speeding bullet) and shield multiple inner "bladders", which contain the module's air, preventing it from escaping. The shell also insulates against the extreme temperatures of outer space, ranging between 121 oC (250 oF) in the sun, to -128 oC (-200 oF) in the shade.
TransHab's MMOD structure (Credit: NASA)
The exterior part of the shell, called the Micro-Meteoroid/Orbital Debris (MMOD) impact shield, is composed of alternating layers of Nextel, a material commonly used as insulation, and several thick layers of foam, similar to that used for chair cushions. A particle that impacts the Nextel and foam layers shatters, losing progressively more energy as it continues to penetrate. Far inside the shell is embedded a layer of bullet-proof, lightweight Kevlar that holds the module shape once inflated and surrounds three air-tight bladders made of Combitherm, a material commonly used in the food-packing industry. The innermost layer, forming the inside wall of the module, is Nomex cloth, which is fireproof and also protects the bladders from scratches from the inside.
Though public interest in Bigelow's space hotel concept is vast, space tourism will remain a costly affair for the near future, out of reach of most people. Thus, Bigelow is building on a number of other lucrative space initiatives; chief among them will be selling space on its future habitats to countries that are unable to afford their own manned space programs . Currently underway is the "Fly Your Stuff" program, an opportunity for paying costumers to send items (smaller than a golf ball) including pictures onboard the Genesis II. For less than $300, an engagement ring can be lofted into orbit where it will be filmed by one of the many cameras installed on the habitat, and returned along with a keepsake video. Perhaps, following a lengthy engagement, the honeymoon could be booked there as well.
TFOT interviewed Bigelow Aerospace Corporate Counsel, Michael Gold, to learn more about the development and future plans of Genesis I and Bigelow Aerospace.
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