Abstract: New step closer to earth. The HDEV it means high definition earth viewing. It is an experiment which is developed by NASA. This system is connected to the international space Station. The system made of four specialized high definition video cameras, role of these cameras are to record video of the earth from multiple angles. The main primary purpose is overcome with problems of data loss, errors, wrong data which transmitted from space and maintenance of hardware system. In this paper, we are going to see what is HDEV, how it works, the purpose of this Experiment and some interesting things yet many readers are unknown from this.

Keywords: HDEV description, operation, application.