June 14, 2003

The post WW-II development of N-weapons and the consequent need for means of delivery and monitoring systems were the primary motivation behind developments of powerful rockets and communication technology. These two technologies happen to be the prerequisites for space travel, that requires devices powerful enough to travel at what is known as the “escape velocity,” to break out of the Earth’s gravitation. The development of rockets and communication technology thus spurred space exploration.

Soon it took the form of a high profile, expensive competition between the US and USSR known as the “space race.” Neither really cared at the time about how justified this enormously costly race was.

Failures and disasters

The destruction of space shuttle Columbia over Texas while descending to Earth after a 16-day mission in February this year, killing all seven astronauts aboard, has once again focused attention on the “manned space flight” aspect of space exploration. Whatever the cause of the disaster, it is clear that the astronauts had no means to fix damage or escape from the shuttle in case a fault developed in space. More than 25 astronauts lost their lives in accidents since space race began with the launch of the Sputnik in 1957. Many accidents were kept secret for reasons of prestige. The Vostok booster explosion during fuelling at ex-USSR’s Plesetsk Cosmodrome in March, 1980, that killed fifty technicians, for example, was reported only in 1989.

Manned versus robotic flights

Opponents of manned flights argue that both economic and technological considerations militate against such perilous journeys. This assertion is not entirely wrong, considering the risks and costs of manned space flight. The cosmic space and time scale dwarfs man, and unless technology advances to a high enough level to surmount problems with ease, manned flights should better be deferred.

The proponents of manned space flights reject these notions outright, pointing out that scientific research has historically been driven fundamentally by man’s perpetual quest for the unknown and not by concern for immediate application. They believe this basic urge cannot be confined by prosaic reasoning. Echoing the above, George W Bush stated after the shuttle disaster: “Exploration is not an option we choose, it is a desire written in the human heart.”

Rhetoric aside, space research was driven more by Cold War rivalry between adversaries than anything else. It is interesting how both US and USSR made use of Hitler’s men in the post WW-II period. Wernher von Braun, Hitler’s chief rocket expert, migrated to the USA alongwith most of his key people, while Sergei Korolev, the Soviet rocket engineer (better known then as the “Chief Designer”) rounded up the rest and took them to Russia. Korolev was entrusted in 1955 with developing the first Soviet ICBMs. Before he died in 1965, he had helped launch the first Sputnik, put in space a dog named “Laika” and send the first man, Yuri Gagarin (April 12, 1961), and the first woman, Valentina Tereshkhova (1963) in orbit.

In the US, militarization of space was already being discussed as early as 1949. US forces were working on plans for a space platform from where ballistic missiles could be fired against the “enemy.” (Marc Richards: “The cold war world” according to My Weekly Reader Monthly Review: Oct, 1998). The ostensible use of such structures was course se “space laboratories” for observations and experimentation.

Roald Sagdeev, a N-physicist who headed the USSR’s Space Research Institute for 15 years, and later taught at University of Maryland, USA, says the Sputnik was launched during the International Geophysical Year to study the upper atmosphere. “The Americans over-reacted to it, and the Soviet government saw the propaganda value of outer space, (and) they devoted more resources to it.” (Steven Savides: “1961: The race for the moon begins.” The Christian Science Monitor: Oct 4, 2001)

In 1961, when the Soviets put Yuri Gagarin in space, they were aware of the risk, and kept handy three press releases before the launch, one for use in case the flight succeeded, and two if it failed — for the alternate events of Gagarin making it safely to Earth or otherwise.

After this Soviet triumph, President Kennedy set the goal before American space experts: land a man on the Moon by the end of the 1960s. He could no more bear to see America as number two in space. Nasa’s Apollo programme, which had an estimated cost of $25 billion, came into being. But many problems needed to be tackled before a lunar flight, and hence an interim Gemini program was instituted that included a series of missions intended to maneuver and dock two orbiting spacecraft, since astronauts would need to do that during the lunar mission.

We are still far from the stage where a single craft would carry out all maneuvers required for inter-planetary journeys. All efforts have been concentrated at the “how” question, and very little on “where,” and the “why and wherefore” aspect of manned flights. Even in the how aspect, several important questions remain: how to store or recycle food, body wastes, breathing gases and generate fuel and power for long journeys. To get answers to the problems arising from weightlessness, radiation in space and isolation on astronauts’ body systems and psyche in long duration space flights, orbiting space stations have been set up to conduct observations and experiments.

Nasa made plans early on for reusable space shuttles to alternate between Earth and space stations. In 1972, when Congress allocated funds for the shuttle but disallowed funds for the space station, the shuttle was used by Nasa for satellite launchings and as platform for scientific experiments.

The shuttle consists of three components: a winged orbiter (containing the crew cabin, three rocket engines for launching, and a 20-m. cargo bay), an external liquid-fuel tank, and two solid rocket boosters. Onboard computers control the shuttle and thousands of heat-resistant silica tiles protect it during reentry into the atmosphere. Upon re-entry, it is steered like a glider by its commander and lands on a runway. The shuttle’s other two components help it reach orbit. The external tank is discarded but the rocket boosters are retrieved for reuse.

Columbia was put into operation in 1984. Shuttle missions deployed, retrieved and repaired damaged satellites, and performed many scientific missions, using up to eight crew members. Reusability was meant to reduce the shuttle’s cost but low number of shuttle flights (only five) per year made the cost per trip jump to $500m. In 1986, twenty four flights were planned but the (shuttle) Challenger’s destruction in an accident immediately after liftoff, in January that year, killing all seven crew, led to the shuttles’ grounding. They were re-commissioned in 1988.

After the dissolution of the Soviet Union, the “Space Race” apparently lost much of its drive. Russia’s space programs were hampered by lack of resources, — overcome partly by marketing strong points of Soviet space technology, such as sturdy launch vehicles, and heavy-duty Russian NK-33 engines to American firms. (Sandy Fritz: “Beyond MIR. Russia’s space program.” Popular Science: 08-01-1994) Economic pressures are not entirely absent in NASA. Many people have begun to question the wisdom of spending too much on space programs while many social problems on Earth linger.

Consequently, joint international programs and experiments aboard permanent space stations orbiting the Earth (“collaboration” rather than competition) have become the norm. Manned flights to planets like Mars could take place jointly by international teams, to share the burden.

Beginning 1995, the shuttle flew several missions to the Soviet space station Mir. The institution of the International Space Station project in 1998 provided the shuttle with a purpose and it began taking crews into orbit to assemble the ISS.

However, space collaboration is not completely smooth, as reports come in of Nasa being hampered from purchasing Russian technology by a US law intended to curb Russian help to Iran’s plans to set up nuclear power stations. The problem is that, with the shuttle grounded again, pending investigation, Russian Progress cargo craft and manned Soyuz are now the sole links to ISS, to move crew and keep the ISS in proper orbit. Russian cargo craft Progress was used to boost the ISS 10.5km higher into an orbit at 406km from Earth, an operation that was to be conducted by a shuttle mission. (Dawn ScienceDotcom: Feb 12, 2003).

A most intriguing question is whether there is life, specially intelligent creatures, on other worlds. A persistent question in the people’s minds is about life on Mars. But to answer these questions, manned spacecraft are not really necessary. Unmanned probes have given much information about the planets. The chances of life’s existence on Mars are rather slim, except perhaps in some rudimentary form, but man’s eyes are fixated beyond the solar system.

Mars, however, is the next destination for manned space flight. It is a harsh environment for man. It has only a rarefied atmosphere, and water locked as polar ice caps, though there is evidence of river flows on its surface eons past. Mariner and Viking craft have revealed astounding features like the huge, two miles deep, over 3000 miles long depression named Valles Marineris on Martian equator and a 17 miles high (three times higher thatn the Mt Everest) volcano named Mt Olympus. Mars has seasons like those on Earth but twice as long. However, the summer temperatures on its surface vary from 23o to -75oC and winter temperatures from minus 58o to -125oC.

Apparently lifeless at present, it might have supported some kind of life in the past. The problems in the journey to Mars (likely to take about a year) are formidable:

— Ensuring the health and performance of the crew,

— Weightlessness over prolonged periods, that causes bone loss and muscle atrophy, weakening of the heart (it has to work less hard under such conditions) and immune system. The remedy is exercise, proper diet and drugs, or maintaining artificial gravity.

While on Mars, the movement of the astronauts over large distances up to 500km or so will have to be in specially designed pressurized vehicles equipped with camera, lights and mechanical arms for scooping up soil samples. Small rover vehicles would be required for movements close to base. The base station must be robust enough to protect against cold and radiation, be pressurized and recycle water and oxygen. Hygiene and waste management facilities and medical treatment are other necessities.

Provisions will be stored along the walls of the craft for the 500 ~ 600 days, the duration that is considered optimal by experts from the point of view of cost and fulfilling objectives of the mission]. An ascent vehicle fuelled by methane and oxygen would take them back to rendezvous with the pre-positioned (by an earlier cargo flight) return module in Mars’ orbit. The return vehicle would land on Earth in a capsule similar to that used by the Apollo missions.

The price tag put on a trip to Mars a few years ago was over $200 billion. Experts believe that such a mission would materialize from 10 years to 30 years from now. If fuel, water and oxygen can be produced on Mars, spacecraft could be smaller and less costly. The crew would consist of experts in specific tasks of mechanical, electrical and electronic engineering, and would include a life scientist, a physical scientist and a physician-cum-psychologist, besides some people having knowledge and training in several fields to provide back-up.

Space research has spin-off benefits, development of new technologies. If the ability in space technologies is taken to such a level that man is able to intercept , say, an asteroid heading towards the Earth and destroy it before it does damage to us, the investment in space research would have paid off. This is a hypothetical, improbable event, but not impossible.

In the very long run, if and when Earth is no longer habitable, or is badly overpopulated, some may decide to migrate to elsewhere in the Universe, to some planet similar to Earth, one that could support human life. Other bodies in the solar system, such as the Moon, or smaller moons of other planets could serve as launching pads for long inter-stellar journeys. Unthinkable at state-of-the-art technology, but revolutionary new technology and methods of travel could make that possible. Understanding and conquering gravity, currently known to act one way only, could be one such breakthrough — reminiscent of HG Wells’ idea in his First men on the Moon (first published: 1901).

Epilogue

During the last about five decades, the Moon has been visited or orbited by more than a score astronauts. Unmanned probes have penetrated deeper into the solar system, where manned flights are impossible, dangerous or unnecessary.

There has been greater appreciation of the risks and costs involved in space exploration after the end of the Cold War. Lowering the cost an d enhancing the safety of manned space flights remains the biggest challenge for scientists today. Cooperation in space exploration is likely to bring multiple benefits, not the least being the sharing of the risks and costs, promoting better understanding and reducing tensions among nations. Besides Russia and the US, many others — the EU, Japan, China — are getting into the business. More nations are likely to join them.

As manned flights to even nearby planets will take years at currently attainable speeds, a main problem is people’s physical and mental health during long duration space missions. Hence the need for long stays at space stations. Unmanned probes can be more productive in terms of return on capital. The rational solution is to put greater resources into unmanned spacecraft, but infinitely greater interest is generated by manned flights, besides being a matter of national prestige for many planners and ambition to be number one. Above all, there is an urge within humans to understand and explore the universe that just cannot be curbed. Space research would yield answers to many puzzling questions, some yet unimaginable, but each individual program has to be weighed on its own merits.

The writer is a freelance contributor

Please Visit our Sponsor (Ads open in separate window)