MRI: Development of the Global Network of Robotic Echelle Spectrographs - NRES

近年来，天文学家已经观测到1000多颗被认为包含类似于我们太阳系的行星系统的恒星，而且新的发现正在迅速增加。为了确认和描述这些系统，有必要对主星进行大量的观测。望远镜收集来自恒星的光，并将其通过光谱仪，光谱仪将光扩散成彩虹状的“光谱”，可以通过分析来确定从地球上观察到的恒星的速度。如果观测到的速度以一种可重复的方式变化，这可能是由于在围绕恒星的轨道上存在伴星。这些观测需要相当多的望远镜时间，而专门设计用于这种高精度工作的望远镜和光谱仪种类不多。这对于所谓的短周期轨道来说尤其成问题，在短周期轨道上，绕轨道运行的行星离它的主星很近，行星的“年”（围绕主星运行一周的时间）可能是几天甚至几小时。为了确定这些天体的轨道特征，需要进行频繁的昼夜观测。然而，当地球绕地轴旋转时，恒星就像太阳和月亮一样落在西方，所以从给定的天文台只能看到它们几个小时。拉斯康布雷斯天文台全球望远镜网络的蒂莫西·布朗博士建议在地球周围的几个望远镜上安装相同的光谱仪，这样就可以在地球转动时连续监测恒星。他和他的团队设计了一个高分辨率和非常精确的光谱仪，他们将复制六个。利用这个摄谱仪网络所作的观测，一定会大大增加我们对行星系统的了解。这项工作由美国国家科学基金会天文科学部通过主要研究仪器项目资助。

In recent years astronomers have observed over 1,000 stars that are thought to contain planetary systems akin to our own solar system, and new discoveries are rapidly being added. In order to confirm and characterize these systems, it is necessary to conduct numerous observations of the host stars. Telescopes collect the light from the star and pass it through a spectrograph that spreads the light out into a rainbow-like "spectrum" that can be analyzed to determine the velocity of the star as viewed from earth. If the observed velocity varies in a repeatable way it may be due to the presence of a companion object in orbit around the star. These observations require a considerable amount of telescope time and there is a shortage of the kinds of telescopes and spectrographs specifically designed to do this high precision work. This is especially problematic for so-called short period orbits, where the orbiting planet is close to its host star and the planetary "year" (the time for a full orbit around the host star) may be days or even hours. To determine the orbital characteristics of these objects frequent observations around the clock are required. As the earth rotates on its axis, however, stars, just like the sun and moon, set in the west, so they can only be seen for a few hours from a given observatory. Dr. Timothy Brown of the Las Cumbres Observatory Global Telescope network proposes to put identical spectrographs on several telescopes around the earth so that the stars can be monitored continuously as the earth turns. He and his team have designed a high resolution and very precise spectrograph and they will build six copies. Observations made with this network of spectrographs is certain to add considerably to our understanding of planetary systems. This work is funded by NSF's Division of Astronomical Sciences through the Major Research Instrumentation program.