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International Space Station The earth as seen from space is perhaps the most profound image of the twentieth century. It dramatises the fragility and interdependence of life on earth, and places the human technological project in a greater perspective. It begs the question: what sort of technology should humans be developing in order to most benefit our planet?
Pat Pillai explains: "NASA has answered this question by committing themselves to building the most complex structure ever place in orbit: The International Space Station (ISS). It will cost about $100 billion. Boeing, the major sub-contractor, compares the scale of the endeavour to the building of the pyramids, thousands of years ago."
The first elements of the ISS, the Russian-built Zarya cargo module, and the American connecting module, named Unity, were boosted into earth orbit late in 1998. At least another 40 missions will be required, using US Space Shuttles and Russian Proton rockets, before the ISS is fully assembled. The completion date is sometime in 2004.
It is a grand project, but is it worth it?
That leaves scientific research as the major justification for building the ISS. NASA claims that it is committed to spreading the knowledge that flows from its space research. But what sort of knowledge are they after, and are there not cheaper ways to get it? Bill Sheperd, the Expedition 1 Commander, explains: "There is a very promising science return that we are hoping to get. The purpose of having a space station in orbit is to pursue areas of scientific research that cannot be done on earth. This will be a hugely beneficial reason for having a space station."
The strongest argument of the space station is the opportunity to study the effect of space flight on human physiology. However, with plenty of data on prolonged human weightlessness already available, courtesy of the Russian Mir space station, critics are asking whether more zero g research is the best way to spend $100 billion.
Even if successful, the research being mooted by NASA will have the single effect of benefiting American competitiveness in the world materials markets and in the burgeoning field of bio-technology. However, is this an appropriate agenda for an international space station? Whatever its intentions, NASA should be proceeding based on the best scientific intelligence available. Since the majority of scientific opinion is against the ISS, the question arises: why are they going ahead with it?
Perhaps the answer lies in the human propensity to explore. Since there are no more terrestrial frontiers to cross, the next colonies may well be on Mars or the moons of Jupiter, and the ISS is the first stepping stone on that journey. The human presence is vital in exploration, and while unmanned probes may do the job, it is simply not the same as being there.
Pat concludes: "Just as the astronauts on board the International Space Station will look down on us, so too will the ISS be visible from earth. But for people looking up from under-developed countries the sight is unlikely to inspire pride or gratitude, but will more than likely signify the ever-widening gulf between the have's and the have not's."
The ISS is a project that may owe more to the human spirit than to the gathering of human knowledge. Our propensity to dream is why the ISS will arc across our night skies, enabling our descendants, in the words of another intrepid explorer, "to boldly go where no man has gone before."
CONTACTS:
NASA website:
NASA Human Space Flight website:
ISS NASA website:
NASA website on the complete construction agenda for the ISS:
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When it is completed, the ISS will be as long a rugby field, have a mass of 460 tonnes and provide 46,000 cubic feet of living and working space for a crew of about seven astronauts. Although NASA is picking up the lion's share of the bill, 16 countries are involved in the construction of the ISS.
Constructing the ISS will require more than 100 space walks. A 58-foot robot arm developed by the Canadian Space Agency will do most of the heavy work, but astronauts will have to venture outside a record number of times to make final connections. According to NASA they will be assisted by a miniature flying robot about the size of a football, that will relay a video signal back to Mission Control.
Since there has never been a project like the ISS, astronauts have had to practice building it on earth. Using virtual simulations and the biggest swimming pool in the world, a 40-foot deep neutral buoyancy laboratory at the Johnson Space Centre, astronauts have practiced the assembly using life-size replicas of the various parts.
The ISS was originally envisaged as a staging platform for a journey to Mars. The Mars craft was expected to be too big for a terrestrial launch, hence the need for a space station. However, as the recent unmanned mission to Mars proved, it is perfectly feasible to send equipment and supplies on ahead, which means that astronauts can reach Mars using smaller rockets launched directly from earth.
Pat continues, pointing out that many scientists disagree. They claim that previous experiments have established how metals and biological processes behave in macro gravity. Further experiments could be done on earth, or on unmanned space flights. The Hubble telescope has demonstrated that space-based astronomy can be done remotely, and existing satellites imply that the ISS will offer limited advantages in terms of "earth watching".
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