If you saw Gravity and were blown away by the sweeping shots of earth from space, now you can get even more. A live HD stream is being aired from the International Space Station (ISS), right now.

The experiment, called High Definition Earth Viewing (HDEV), was launched as cargo on the SpaceX Dragon spacecraft on 18 April. Four cameras have been setup on the ISS and can be viewed live via Ustream now.

If you get a dark image that's because you've tuned in when the ISS is in its night cycle. As you can see from the photo there are some pretty impressive moments worth checking back for. You'll also hear the radio transmissions back and forth between earth and the space station.

Part of the test is to try out the hardware to see how it survives and functions for long periods of time in space. Some of the components were designed by schools as part of the High Schools United with NASA to Create Hardware (HUNCH) program.

At the time of publishing we were enjoying some lovely shots that clearly show the earth in daylight. What have you spotted?

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