The Global‐scale Observations of the Limb and Disk (GOLD) is a National Aeronautics and Space Administration mission of opportunity designed to study how the Earth's ionosphere‐thermosphere system responds to geomagnetic storms, solar radiation, and upward propagating atmospheric tides and waves. GOLD employs an instrument with two identical ultraviolet spectrographs that make observations of the Earth's thermosphere and ionosphere from a commercial communications satellite owned and operated by Société Européenne des Satellites (SES) and located in geostationary orbit at 47.5° west longitude (near the mouth of the Amazon River). They make images of atomic oxygen 135.6 nm and N₂ Lyman‐Birge‐Hopfield (LBH) 137–162 nm radiances of the entire disk that is observable from geostationary orbit and on the near‐equatorial limb. They also observe occultations of stars to measure molecular oxygen column densities on the limb. Here, we provide an overview of the instrument and compare its prelaunch and early flight measurement performance. Direct comparison of LBH spectra of an electron lamp taken before launch with spectra on orbit provides evidence that both cascade and direct excitation are important sources of thermospheric LBH emission.

中文翻译：

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肢体和磁盘任务执行的全球规模观察：1.仪器设计和早期飞行性能

全球肢体和盘片观测（GOLD）是美国国家航空航天局的一项使命任务，旨在研究地球的电离层-热层系统如何响应地磁风暴，太阳辐射以及向上传播的大气潮汐和波浪。GOLD使用的仪器具有两个相同的紫外光谱仪，它们是从欧洲兴业银行（SES）拥有和运营的，位于地球静止轨道西经47.5°（位于地球入口附近）的商业通信卫星观测地球的热层和电离层的。亚马逊河）。他们使原子氧135.6 nm和N ₂成像Lyman-Birge-Hopfield（LBH）整个磁盘的137-162 nm辐射，可从对地静止轨道和近赤道肢观察到。他们还观察恒星的掩星，以测量肢体上的分子氧柱密度。在这里，我们提供了该仪器的概述，并比较了其发射前和早期飞行测量的性能。直接将电子灯发射前的LBH光谱与轨道上的光谱进行比较，可以证明级联和直接激发都是热球LBH发射的重要来源。