Watch NASA’s 24/7 HD live stream of earth from the Space Station

NASA launched a High Definition Earth Viewing HDEV experiment in the trunk of the SpaceX Dragon spacecraft and has set it up outside the International Space Station. Four HD cameras were installed on the External Payload Facility of the ESA Columbus moduleare and are now fully operational, which were enclosed in a pressurized box to provide protection to the equipment from the harsh environment of space.

Another cool thing is that the whole experiment is part of a student project, with High school students having designed some of the HDEC components and overseeing the equipment, and The HDEV does not record video on board the ISS, but all video is transmitted to the ground in real time.

Pleas note that The video feed will be running 24/7, although it may appear black when the ISS is in orbital night which occurs every 90 minutes for around 40 minutes.
Here's a graph explaining how the whole thing works.