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Space and astronaut, where is the Space Station?

With or without horizon

 Automatic translation  Automatic translation Updated May 28, 2014

Since its first launch in 1998, up 9 astronauts permanently occupy the International Space Station. Confined in their solitude, away from sunlight, astronauts paradoxically see the immense space that surrounds the Earth, while they themselves are kept in a small space considerably. They glide at the speed of 7.7 km / s in low Earth orbit and eyes traverse the vast land areas scrolling "under" the station. They attend every day about 16 sunrises and sunsets. But it is "downward" in the night they see their only horizon, the Earth.
The spectacle of the night offers them red and green lights, as well as lights of big terrestrial cities with in the background, multicolored stars. The atmosphere of the Earth reflects sunlight..

NB: Weightlessness or zero gravity?
The term zero gravity that is used in everyday language, but today it is preferred that weightlessness. Weightlessness is a theoretical state because it does not exist in the universe, there is always in the cosmos a residual gravity. On board a spacecraft, speaking generally microgravity. Microgravity has a value of one millionth of the Earth's gravity.

 Free flight into space

Image: The first free flight of an astronaut in space, dates from 1984. Astronaut Bruce McCandless became the first man to move freely with an MMU (Manned Maneuvering Unit), it is propelled by jets nitrogen. One can easily imagine the anxiety can feel a man flying at 27 700 km / h in this state of weightlessness, with as horizon our planet.

 Space of the astronaut

Image: The International Space Station is a 400-ton structure, stuffed with technology. With its 110 meters wide, 74 meters long and 30 meters high, the station orbit at 415 km altitude. Here, the NASA astronaut Reid Wiseman when preparing the launch of May 19, 2014 in Kazakhstan. Its only horizon is his cabin.

Where is the Space Station?


The International Space Station (ISS) is very close to the Earth and it is clearly visible at night because it reflects sunlight, thanks to its huge solar panels. When it flies over your region, you can see it and photograph it without special equipment. Because of its high speed, it is not always easy to know when and where to observe. This dynamic map shows in real time where is the Space Station, it orbits around the Earth at about 415 km altitude at the rate of ≈ 7.7 km / s. 
This tool allows you to track its position in real time. Once you know when and where it will go, wait for dawn or dusk. Space Station looks like a big bright star moving across the sky about one degree every second. To photograph, use a tripod and set the exposure time of more than one minute. On the photo you see on sky background, a large white stripe. The ISS comes from the West.
In the preview window, you can also choose to view the position of the Hubble Space Telescope or environmental satellite Envisat ESA.


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