论文标题
Starlink卫星的平板亮度模型和其绝对视觉幅度的测量
A Flat-Panel Brightness Model for the Starlink Satellites and Measurement of their Absolute Visual Magnitude
论文作者
论文摘要
Starlink卫星的形状像平面面板一样。在正常操作过程中，平坦的侧面面向天顶和纳迪尔。它们的亮度取决于面板的向下侧面太阳照明的乘积乘以向地球上观察者投射的那一侧的区域。这种几何形状导致了独特的亮度功能，而其他卫星则不共享。例如，观察到的亮度对太阳高度角度非常敏感。在某些情况下，阳光只会照亮卫星的向上面，从而使基于地球的观察者看不见。除了卫星距离之外，还取决于太阳能方面和观察者方面的亮度模型。绝对亮度是模型的唯一自由参数，当太阳能和观察者因子是统一时，它被认为是在1,000 km的距离处。该模型已成功拟合到一组观察到的幅度。根据该拟合确定的星链卫星的绝对视觉幅度为4.1 +/- 0.1。该模型可用于确定具有特殊的低α涂层的Starlink卫星的绝对大小。
The Starlink satellites are shaped like flat panels. The flat sides face zenith and nadir during normal operations. Their brightness is determined by the product of the solar illumination on the downward facing side of the panel multiplied by the area of that side projected toward the observer on Earth. This geometry leads to a unique brightness function that is not shared by other satellites. For example, the observed brightness is very sensitive to the solar elevation angle. There are circumstances where sunlight only illuminates the upward facing side of the satellite rendering it invisible to Earth-based observers. A brightness model depending on the solar aspect and the observer aspect of the flat panel, in addition to the satellite distance, is described. Absolute brightness is the only free parameter of the model, and it is taken to be that at a distance of 1,000 km when the solar and observer factors are unity. This model has been successfully fitted to a set of observed magnitudes. The absolute visual magnitude of a Starlink satellite as determined from this fitting is 4.1 +/- 0.1. The model could be used to determine the absolute magnitude of the Starlink satellite known as Dark Sat which has a special low-albedo coating.
