International Space Station Jigsaw Puzzle

The International Space Station is the largest and longest inhabited craft to have ever orbited the Earth. It represents the co-operation of 15 different nations who have joined together to design and build the station itself as well as carry out scientific studies both inside and outside the station. The microgravity of the ISS enables experiments to be done which could not be carried out on Earth. Studies include medicines, physics, biology, astronomy and looking at how the human body copes for extended periods in the weightlessness of space, something that will be important for any manned missions to Mars for example. The station is currently funded until the year 2020 for scientific experiments. It is thought that it may remain in operation until 2028 however, with the possibility of it being used as a base from which to launch manned missions to the Moon, Mars or even a nearby asteroid.

The International Space Station's first component, known as Zarya (Russian for "Dawn", signifying the start of a new era), was brought to space on a Russian Proton rocket which was launched on 20th November 1998 from Baikonur Cosmodrome in Kazakhstan. This did not have long-term life support functions, so initially at this stage the station was uninhabited. Two weeks after Zarya, the second module known as Unity was carried by the Space Shuttle Endeavour on flight STS-88, and attached to Zarya by astronauts on spacewalks.

It was only when the third component, the Zvezda (Russian for "Star") Service Module was attached on 26th July 2000 that the International Space Station became ready for human habitation. The first actual occupants, Commander William Shepherd, Pilotr Sergei Krikalev and Flight Engineer Yuri Gidzenko, launched on 31st October 2000 from Baikonur Cosmodrome. Their spacecraft, the Soyuz TM-31, docked with the International Space Station on 2nd November 2000, and so began their 136 days, 17 hours and 9 minutes stay in the station. Since theses first occupants, knowns as Expedition 1, the station has been permanently occupied.

According to NASA it takes two and a half people to maintain housekeeping tasks on the Space Station. Normally it is crewed by three astronauts, which leaves half a person to carry out scientific experiments. The aim, as the station grows, is to eventually have 7 people onboard, allowing much more time to be devoted to scientific study.

The average stay of a 3 person crew is around 160 days. The longest a crew has lived aboard the ISS is 215 days, this record being held by the Expedition 14 crew commanded by Michael López-Alegría,