06/05/2014 07:02 BST | Updated 06/05/2014 07:59 BST

Live ISS HD Stream: Nasa Launches Incredible View Of Earth Below The Space Station

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Nasa has finally done the obvious thing, and stuck a webcam on the International Space Station.

In fact it's got four - all in HD - which are broadcasting live HD footage of the Earth rolling underneath.

The cameras are sensitive instruments, and are housed in temperature controlled cases with dry nitrogen inside.

The images are sent back to Earth and reformatted, before being sent out live on the internet at pre-arranged times. The footage is not constant, and is at times totally dark depending on the position of ISS relative to the Sun. Watch long enough and you can see a sunrise or sunset every 45 minutes.

While the crew is on duty the cameras will provide a view of the inside of ISS. When the crew is off duty, it will turn again to the Earth.

But watch the video at the right time and the result is startling - a live, rolling view of our planet that only astronauts usually get the chance to see.

Nasa said the aim of the experiment is to test how the cameras work in space, and what effect radiation has on the equipment.