On the early morning of August 13th, China successfully launched the Land Exploration 4 01 satellite using the Long March 3B carrier rocket at the Xichang Satellite Launch Center, and the satellite entered the predetermined orbit. The launch mission was a complete success. This satellite is the world's first high-orbit synthetic aperture radar satellite to enter the implementation stage of engineering. It will further improve China's space-based disaster monitoring system and is of great significance for comprehensively improving China's comprehensive level of disaster prevention, reduction, and relief. The Landsat 4 01 satellite is a remote sensing research satellite in the "National Medium and Long Term Development Plan for Civil Space Infrastructure (2015-2025)". The satellite operates in a tilted geosynchronous orbit and is equipped with synthetic aperture radar payload, which has advantages such as high resolution, wide coverage, multi-mode, and lightweight. Compared with low orbit satellites and optical satellites, this satellite combines the advantages of short revisit cycles and large imaging widths in high orbit observations with the advantages of microwave observations that are not limited by climate (all weather) or light (all day), which can improve the accuracy and efficiency of identifying abnormal changes in disaster information and enhance the comprehensive prevention and control capabilities of natural disasters. After the satellite is launched into orbit, it will enrich the observation methods in key regions of China, enabling 24-hour observation of the local and surrounding areas, meeting the application needs of disaster prevention and reduction, earthquake monitoring, land and resource exploration, as well as industries such as ocean, water conservancy, meteorology, agriculture, environmental protection, and forestry. It is reported that the National Space Administration is responsible for the organization and management of the Land Exploration No. 4 01 satellite project, the organization and coordination of major matters, and the approval of launch permits. The National Space Administration's Earth Observation and Data Center is responsible for the overall engineering work; The Emergency Management Department (leading), the Ministry of Natural Resources, the Ministry of Water Resources, the China Meteorological Administration, the Ministry of Agriculture and Rural Affairs, the Ministry of Ecology and Environment, and the State Forestry and Grassland Administration are user departments responsible for the construction and operation of their respective application systems; The China Resources Satellite Application Center and the Aerospace Information Innovation Institute of the Chinese Academy of Sciences are responsible for the construction and operation of ground systems; The Fifth and First Institutes of China Aerospace Science and Technology Group are respectively responsible for the overall development of satellite systems and launch vehicle systems. Zhang Yunlong, the overall designer of the Long March 3A series carrier rocket model of Aerospace Science and Technology Group, introduced that the rocket development team has carried out more than 10 optimization improvements on the rocket and ground equipment, involving conventional engines, low-temperature engines, software, and other aspects, further improving the reliability of the rocket. At the same time, the development team is continuously improving and improving management, strictly controlling quality and preventing risks, exploring and implementing job integration, streamlining launch site personnel, and ensuring success with high quality and efficiency. In order to better serve the disaster prevention and reduction work of satellites, we fully utilize the characteristics of high orbit and microwave, closely follow the characteristics of disaster occurrence and observation needs, and carefully design four application modes for satellites to provide more accurate and professional services for disaster prevention and reduction. "said Zhang Qingjun, the commander and designer of the Land Exploration No. 4 01 satellite of the Fifth Academy of Aerospace Science and Technology. (New News Agency)