Introduction
A space station can be defined as a man-made structure built for humans so that they can live in outer space. The concept of the space station was brought about in 1869 by Edward Everett when he described the Brick moon a satellite used to navigate ships in the ocean. Today only the low earth orbit also known as orbital stations have been built. Unlike vehicles, space stations are built to live in the orbit as per the period assigned (Waber, 1998).
On the other hand, the international space station is the world’s largest and most complex research facility being assembled in low earth orbit. It is located at 360 km altitude on an orbit that goes around the Earth and goes around the Earth in one and half hours. It is considered to be the biggest satellite in the whole universe. Its construction began in 1998 and is targeted to end by the year 2011 with an extension of four years to completely end in 2015.
The international space station program is a joint venture between the National Aeronautics and space administration (NASA) of the United States of America, Russia Federal Space Agency (RKA) of Russia, Japan Aerospace Exploration Agency (JAXA) of Japan, Canadian Space Agency (CSA) of Canada and European Space Agency ( ESP) of the European Nations (Launus, 1998). Since the first expedition, the international space station has had staff continuously, thus providing a permanent human presence in the station. In the beginning, only the Russian and the American crew members boarded the space station, they were later joined by Thomas Reiter from Germany in the year 2006. Today the station has been visited by many astronauts from different nations.
Origin
International Space Station originated during the cold war. During this time NASA was planning to launch an exemplary space station called Freedom as a copy to the Soviet Slyut and Mir space station. On the other hand, the Soviet was planning to build another space station called Mir2. However, due to financial and design obstacles, space station freedom did not go past the mock-ups and component tests.
After the cold war, the United Nations nearly canceled Space station freedom and due to the soviet economic crisis, Mir2 space station was canceled (Launius, 1998). These problems and other obstacles to space station construction were being experienced by other nations that tried to build the space station. This triggered the beginning of negotiations between these nations which included; Russia, Europe, Japan, America, and Canada, to collaborate in a multi-national space station project.
In 1992 the then US president George W. Bush and the Russian president Boris signed an agreement that called for a short joint venture between the two nations. In 1993 the then US Vice president Al Gore and the then Russian Prime Minister Viktor Chemomyrdin came up with plans for building a new space station which eventually became the International Space Station. The international space station’s aim was to combine all the proposed space stations of all other nations with a mission of enabling long-term space exploration thus providing benefits to the people of the earth. The station will also provide a permanent orbiting station for long-term research on the material and life forms in space. To add to this, due to its unique conditions it will facilitate major research in technology and engineering (Neeson, 2000).
The purpose of the international space station
One of the reasons why the international space station was constructed was to provide a conducive environment for conducting experiments that require unusual conditions that can only be found in space, for instance, microgravity conditions. The station offers an advantage over other space crafts as it provides long-term conditions in the space environment thus allowing studies to be performed. With the main research being biology, physics, astronomy, and meteorology the United Nations designate their segment in the international space station as a national laboratory. This allowed for the utilization of the international space station by other nations and the private sector (Bond, 2002).
The international space station also provides a favorable testing place for efficiency and reliability for spacecraft that will have a long mission to the Moon and Mars. This is because it allows for the evaluation of equipment in a safe low Earth Orbit location. This gives an experience in maintaining, repairing, and replacing systems that will be required in driving the spacecraft from the Earth. This reduces mission failure risk and enhances the capability of the spacecraft to complete the mission successfully.
In addition, the international space station allows for the study of human muscles, bones, and fluid change in human bodies due to the long exposure of human beings in space. This will help in space living and allow for lengthy space travel.
In addition, the international space station provides the best place to study the effects of near-weightless on other objects besides human beings. The study is focused on plants and other animals so as to establish an outer space environment that will support the development and growth of these subjects (Waber, 1998).
Last but not least international space station provides opportunities for educational tours and international joint venture. The crew aboard the international space station provides educational opportunities to students on Earth, this is done by allowing students to participate in the classroom of international space station experiments, educational demonstrations, among others. Due to the fact that the crew aboard the international space station comes from different nations the important lessons learned are forwarded to their nations and to future multi-national missions (Launius, 1998).
Assembly and Structure
The assembly of the international spaceship started in 1998 and by early2009 it was considered 81 percent complete. In 1998 the first segment of the international space station, Zarya was launched, this was followed by the first three node modules, unity. The station was stagnant for the next one and half years and it was only in 2000 when the Russian model Zvezda was added. This allowed for at least three crew members to board the station. Later in the year 2000, two segment of the station’s Integrated Truss Structure (Z1 & P6) arrived. This enabled communication, guidance, electrical and power sharing via two solar array wings. In 2003, however, a space ship named Columbia hand an accident and this brought the work on the international space station to a stop.
The work on the international space station however, commenced again in 2005 when another space ship name discovery was launched. This was followed by second set of solar arrays and the third set. With these solar arrays more pressurized modules were required and this lead to the addition of harmony node and Columbia node (Bond, 2002). In 2009 more solar arrays were brought in and this marked the last pair of solar arrays. To date work on the international space station still goes on with more and more pieces of it expected to come in and be joined. The final stage of the international space station is expected to end in the year 2011 but the astronauts are still adding more equipments or segment to the station thus furthering the completion date to the year 2015.
Power Supply
The international space station utilizes the sun as its main source of power. The sun energy is transformed to electric energy by the solar arrays that have been installed in the international space station. In international space station, power is very important as it help pumping clean air and water in to the station. The electricity power is also very important as it illuminates the station and providing energy for pumping the oil need in the station.
In the beginning the only source of energy for the station was the solar panel fixed on the first modules (Zarya &Zvezda). The total power that is converted by the solar arrays is about 130 to 180 volts. This power is used by the whole station. In power transportation only small power lines are used so as to reduce weight in the station. Recently the Russian Science power Platform has been installed and this has enabled power sharing in the station (Neeson, 2000).
In trapping the solar energy, the arrays move as the earth moves by rotating so that they always face the sun, this is aided by the alpha gimbals while the beta gimbals held in getting the right angle for the sun rays. This ensures that there is constant energy flow in the international space station (Waber, 1998).
Work Cited
Bond, P. the Continuing Story of International Space Station. (2002). New York.
Waber, M. E. International Space Station Countdown to Launch. (1998). Alexandria.
Launius, R. Space Stations. The Origin of International Partnership in International Space Station. (1998). Washington.
Neeson, L. Inside the Space Station. A Fantastic First Step to Life off Earth. (2000). Santa Monica. Web.