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Space scientists are preparing to celebrate a remarkable astronautical achievement. In a few days they will mark the 20th anniversary of humanity’s continued presence in outer space.
For two decades, teams of astronauts have made their homes 250 miles above our planet through their uninterrupted occupation of the International Space Station (ISS). First inhabited by American astronaut Bill Shepherd and Russian cosmonauts Sergei Krikalev and Yuri Gidzenko on November 2, 2000, the ISS has since provided shelter for a constant rotation of crews that has ensured that the station has never been left unoccupied. .
A total of 240 men and women have set up camp at the 420-ton station as it has swept the Earth at 17,000 mph, making 16 orbits of our world every day. Accommodation at the 109-meter-long station includes six bedrooms, two bathrooms, a gym and, most popular of all, a European-built set of bay windows, called Cupola, which offers 360-degree views and allows guests to astronauts Watch as the storms have built up and the Sun has risen over Earth.
Tim Peake, the only official British astronaut to make it to the ISS, was a particular fan of the Cupola, where, he says, he first looked at our planet and realized how fragile it is. “You can see the atmosphere, which is only 16 km thick. It is not endless, ”he recalled in an interview with the BBC. “All the gas that keeps us alive on Earth is trapped in that tiny, tiny layer. Suddenly you realize that what we put on that layer is really important. “
The more mundane aspects of station life have included guitar serenades by floating astronauts; a piece of culinary history made by Italian astronaut Samantha Cristoforetti, who drank the first espresso made in outer space in a zero-gravity cup; and dealing with a series of broken toilets: “I discovered the part of the station that attracts the most curiosity on Earth,” says Peake. And these domestic details are important, the scientists insist. “The operation of the International Space Station has shown us that humans can make their homes far from their own planet in outer space, which is a truly hostile environment,” said astrobiologist professor Charles Cockell of the University of Edinburgh. “That has been a very important lesson for us.”
Plans to build a permanent orbiting space station were first drawn up in the 1980s by NASA. However, cost forecasts indicated that these would be alarmingly high, until the collapse of the Soviet Union offered an opportunity to cooperate with Russia. Its space engineers had already gained considerable experience in long-term space missions with their own small orbiting Salyut stations and the much larger Mir station.
“It was also a very pragmatic move by the United States,” said Professor Anu Ojha, director of the Leicester National Space Center. “The United States wanted to prevent Soviet space experts from being captured by rogue states when the USSR disintegrated. So he sought to get them involved in a joint space program so he could keep them home and give them some degree of involvement. The ISS was perfect for that. “
In the end, the two nations agreed on a plan for the construction of the ISS, and the Canadian and Japanese space agencies also agreed to join the project, along with the European Space Agency, of which the UK is a key member. Assembly of the station began in 1998 and required more than 30 American space shuttle flights and 40 Russian rockets to bring components and modules to the station before its completion in 2011. For years, astronauts were concerned about building the station, And only relatively recently have they been able to focus on doing serious science, including running more than 3,000 experiments in collaboration with thousands of scientists on Earth.
The final bill for the construction of the ISS amounted to more than $ 100 billion. The station absorbs $ 4 billion a year in maintenance costs and service flights. Most of this has been paid for by the United States. The question is: was this huge expense worth it?
Planetary science expert Professor Ian Crawford of Birkbeck, University of London, thinks so. “The ISS is a fantastic example of high-profile international cooperation at a time when the world desperately needs examples of activities that can bring people and nations together. And learning to live and work in space will be of great use to us as we prepare to return to the Moon and possibly send people to Mars. “
However, other scientists take a different position. “There is no way you can justify the huge sums that have been spent building the ISS,” said Astronomer Royal Sir Martin Rees. “To begin with, the scientific results have been scant. We have learned a bit about how the body reacts to spending long periods in space, and we have grown some crystals in zero gravity, but that is by no means proportional to the tens of billions of dollars that have been spent on the EEI. Really, the station only gives news when its toilets are blocked or an astronaut sings while floating with a guitar.
NASA money would have been better spent launching robotic missions to other planets or building orbiting observatories, added Rees, a view backed by Nobel laureate physicist Steve Weinberg of the University of Texas at Austin. “The only interesting science done on the ISS has been the study of cosmic rays by the Alpha Magnetic Spectrometer, but astronauts played no role in its operation,” he told the Observer. “It could have been put into orbit much cheaper by an unmanned mission.”
Ojha added that he initially had many doubts about the scientific justification for the ISS, but was now convinced that it was a great success. “What we have achieved in terms of experience in manned space flight, space engineering and scientific performance has been immense. We have learned to mount huge structures in space and to live for long periods there while dealing with all kinds of incidents that have arisen. It is essential that we do not waste that experience. “
A key lesson learned from studying ISS astronauts has been the impact of prolonged periods of zero gravity on the human body. These include loss of muscle mass, reduction in bone density, and impaired vision and taste. Scientists have found that it can take several years for an astronaut to regain his bone density after a four or five month space mission. On the other hand, by using treadmills and weight machines, astronauts can avoid the worst effects of muscle wasting.
NASA is scheduled to continue funding the ISS for four to five years and has said it hopes private companies will take over and run it commercially as the agency funds more cutting-edge missions to explore and settle on the Moon, and possibly one day. take humans to Mars. These projects will include the construction of Gateway, a smaller version of the space station, in orbit around the Moon as a stopping point for exploring the lunar surface.
But, is the private company interested in taking over the ISS? Several companies have expressed interest from the beginning saying they want to work there. Texas-based company Axiom Space has signed an agreement with NASA to build a module where research would be conducted on novel materials; Actor Tom Cruise and Director Doug Liman are scheduled to fly to the station next year in a SpaceX Crew Dragon capsule to film scenes for an action-adventure movie; and the next reality show, Space hero – scheduled for screening in 2023 – has announced plans to send a winner to the ISS.
It remains to be seen whether companies like these will be enough to provide the billions of dollars needed to operate the station. The alternative would be to dismantle the ISS and send its components spiraling towards Earth in the hope that they would be destroyed as they burn up in the atmosphere.
And that would be a terrible waste, says Cockell. “It was a big effort to get everyone to agree on the station and then build it. We would have little chance of building another in the near future if we lose this one, so we must encourage companies to keep the station running for at least another decade. “
