Solar Variability and Climate: The Balloon-Borne Solar Disk Sextant

研究人员将探索太阳直径在几年到几个世纪的时间尺度上是否存在系统性变化的可能性。这种变化及其对太阳总辐照度的影响会影响天气和/或气候。主要工作是对从太阳盘六分仪飞行中获得的数据进行详细分析。太阳盘六分仪是一种气球载仪器，于1992年首次使用。对单个飞行的分析表明，该仪器能够测量太阳直径，精度达到所需的十万分之一，但迄今为止，系统影响导致飞行间的差异要大得多。在目前的项目中，首席研究员将与光学天文仪器的校准专家合作，以了解和纠正过去数据的系统影响。如果这项努力取得成功，将与美国宇航局戈达德太空飞行中心合作进行更多的有效载荷飞行。

The investigators will explore the possibility that there are systematic changes in the diameter of the sun on timescales ranging from years to centuries. Such changes, and their consequent effect on total solar irradiance, can affect weather and/or climate. The main effort is to conduct a detailed analysis of data obtained on flights of the Solar Disk Sextant, a balloon borne instrument first operated in 1992. Analysis of individual flights has demonstrated that the instrument is capable of measuring the solar diameter to the required precision of one part in 100,000, but systematic effects have to date resulted in flight to flight variations much larger than this. In the present project, the principal investigator will work in collaboration with experts on the calibration of optical astronomical instruments to understand and correct for the systematic effects in past data. If this effort is successful, more flights of the payload will be made in collaboration with the NASA Goddard Space Flight Center.