Where is the ISS?

The ISS orbits the Earth at a distance of approximately 400 km from the Earth. Even though this might seem far away, you can actually see it from Earth with your bare eyes on a clear night. When visible, the ISS looks almost like a wandering star, moving through the sky. The best time to see it is either just after sunset or just before sunrise. At this time we as observers are in the shadow of the Earth and it is dark around us, while the ISS, flying at a high altitude, is still illuminated by the sun.

Even though the ISS always follows the same orbit when travelling around the Earth, the ISS does not pass the same places on Earth every time. This is because the Earth also rotates around its own axis once every 24 hours. Every time the ISS reaches the same point in its orbit, the Earth has rotated and a new place will be underneath the Space Station.

	Explanation: (A) The map of the world. (The dark area indicates where it is night at this moment.) (B) The International Space Station; the centre represents its current latitude/ longitude. (C) The blue line tracks the International Space Station's flight path over the ground. (D) The red circle around the International Space Station represents its horizon (the area on the ground from which the ISS is visible). (F) The yellow disc represents the Sun's zenith (high noon on earth).

The ISS’ orbit will cover 85% of the Earth’s surface, including the countries that are home to 95% of the world’s population. Only the northernmost and southernmost areas of the world cannot see the ISS.