The reporter learned from the Space Application Engineering and Technology Center of the Chinese Academy of Sciences that China has successfully built a three-star constellation consisting of three satellites in the earth moon space, and will focus on the earth moon space long distance retrograde orbit (DRO) for in-depth scientific research. Long distance retrograde orbit is a lunar orbit that is opposite to the direction of the moon's revolution. A typical type of orbit is about 70000 to 100000 kilometers away from the moon and serves as a "transportation hub" connecting the Earth, the moon, and deep space, known as the "natural harbor" of the Earth Moon space. Exploring this' natural harbor 'will provide strong support for the development and utilization of Earth Moon space, as well as cutting-edge exploration in space science. It is reported that after the interconnection of DRO-A, DRO-B, and DRO-L Samsung networks, multiple cutting-edge scientific experiments and new technology experiments have been carried out, promoting a series of important progress in the exploration and research of DRO in the Earth Moon space. (New Society)