云层对近红外白天测星的影响

大气层内白天测星最大的困难是过强的天空背景辐射,白天近红外波段可以探测到足够多的星体用以导航。目前已有研究针对理想情况下的白天恒星探测进行了分析,然而,对于实际情况来说,天空背景很难像理想分析中那样无风无雨无云,尤其是云层自身的热辐射及散射的太阳辐射对近红外白天恒星探测造成极大的影响;根据经验公式,对云层和太阳的红外辐射进行计算,分析了白天云层对恒星探测的影响,并以层云和积云为例,具体分析了恒星辐射透过云层的衰减,对实际工作具有一定的指导意义。

Influence of cloud on near-infrared star detection during daytime

The strong sky background radiation is the biggest difficulty for star detection during daytime, and NIR can detect sufficient number of stars for navigation during daytime. At present, star detection under the ideal situation has been analyzed during daytime. However, for the actual situation, sky background is much different as the ideal situation, especially clouds has thermal radiation and scatter the solar radiation during daytime. It has great effect on star detection;the radiation of clouds and sun is calculated through empirical formula, the influence of clouds on star detection is analyzed. Using the stratus and cumulus clouds as an example, the star radiation attenuation through the clouds is specifically analyzed. It is helpful to the practical work.