空间对地观测及应用是发展航天技术的核心使命之一。至今为止，国际上已发射了几千颗航天器。其中，对地观测卫星占有重要分量，是为经济发展、国家安全及环境、能源等领域的需求直接带来效益的、不可替代的航天技术领域。几十年的发展表明，国际上把对地观测技术作为重中之重技术发展。我国对地观测技术是上世纪70年代初开始，至今已走过四个发展阶段，已成为谱段齐全、数据获取技术有了较大发展、应用领域不断拓展、有较深入的基础研究及处理方法的初具规模的技术科学体系，几十年来在国民经济发展、国家安全建设中已发挥了重要作用。在我国中长期科技发展规划中，有多项相关对地观测的重大事项和研究项目。我国对地观测将以需求牵引、技术驱动，面向国际前沿，力争在对地观测领域跻身国际先进行列。

Earth Observation and application is one of the core missions in space technology development. Up to now, over thousands of spacecrafts have been launched, and earth observation satellites occupy a very important position. It has become an area of no substitute, which can bring profit to economic development, national security and demands on environment and resources. The development over decades shows that earth observation technology has become a strong trend around the world. In China, earth observation Technology started from 1970s. Up to now, it has developed over four stages and has acquired considerable scale in the technology system, which spans the spectrum and achieves considerable development in data collecting. Besides, the application is expanded and in-depth basic research and processing methods have been set up. In the National Long-Term Technology Development Program, there are severalimportant items and research projects relevant to earth observation. In China, earth observation technology will abide by the principle of “Demand Pulls, Technology Pushs”，aiming at coming up with international advanced technologies.