太阳极紫外光谱探测的历史与展望

More than 70 years of the space-borne solar exploration clearly shows that Extreme Ultraviolet (EUV) wavelengths are very useful for observations of the solar transition region and corona. Because of this, almost all of the current and future solar space missions have EUV payloads. Unfortunately, China has never sent a solar EUV spectrometer to space so far, which significantly restricts the chance for Chinese solar physicists to have original discoveries and breakthroughs. Now it is the right time to develop our own payloads and contribute to space exploration of solar physics. In the paper, the characteristics of solar irradiance as well as the common optical elements at EUV wavelengths are introduced firstly. The history, current status and future perspectives of solar EUV spectroscopic observations are systematically reviewed, including the instrument designs and major scientific achievements. Three major types of spectroscopic observations are focused on, i.e., full-disk integrated irradiance measurements, low-speed spectroscopic imaging observations with a certain spatial resolution and two-dimensional fast spectroscopic imaging. Then, a three-step development strategy is proposed to start Chinese solar EUV spectroscopic observations in space. The scientific objectives, observational requirements and candidate schemes of each step are discussed. Moreover, a solar EUV imager working at a wavelength that has never been done before is suggested. Once the above explorations are successfully implemented, major advances towards our understanding of many unsolved solar mysteries will be made, including the accurate speed estimation of coronal mass ejections and forecast of their arrival times at the Earth, the origin of solar wind and coronal heating mechanism, as well as the generation mechanism of solar eruptions. It will significantly elevate the level of key technologies involved in ultraviolet space explorations, too.