天文年历中的视行星星等计算
Computing Apparent Planetary Magnitudes for The Astronomical Almanac
摘要：
本文报道了计算行星星等的改进方程。这些公式模拟了从20世纪50年代最早的滤光光度测量到现在的V波段观测。新的方程包含了几个以前没有用于生成物理星历的术语。这些包括火星的自转和公转角度，天王星的太阳下和地球下的纬度，以及海王星的长期时间依赖性。天文年历中使用的公式涵盖了从地球上可见的行星相位角。补充方程涵盖了超出地心限制的那些相位角。地心星等是在至少50年的时间跨度内计算的，并对结果进行了统计分析。报告了每颗行星的平均值、变化和极端星等。简要讨论了Johnson-Rupins和Sloan测光系统中除V以外的其它谱带。美国海军天文台提供的行星星等数据产品也被列出。附录描述了源代码和测试数据集，这些数据集可用于根据本文给出的方程和情况在线计算行星星等。这些档案作为本文件的补充材料张贴。它们也可以在SourceForge的项目https://sourceforge.net/projects/planetary-magnitudes/下的“文件”选项卡下的“Ap_Mag_Current_Version”文件夹中找到。
英文摘要：
Improved equations for computing planetary magnitudes are reported. These formulas model V-band observations acquired from the time of the earliest filter photometry in the 1950s up to the present era. The new equations incorporate several terms that have not previously been used for generating physical ephemerides. These include the rotation and revolution angles of Mars, the sub-solar and sub-Earth latitudes of Uranus, and the secular time dependence of Neptune. Formulas for use in The Astronomical Almanac cover the planetary phase angles visible from Earth. Supplementary equations cover those phase angles beyond the geocentric limits. Geocentric magnitudes were computed over a span of at least 50 years and the results were statistically analyzed. The mean, variation and extreme magnitudes for each planet are reported. Other bands besides V on the Johnson-Cousins and Sloan photometric systems are briefly discussed. The planetary magnitude data products available from the U.S. Naval Observatory are also listed. An appendix describes source code and test data sets that are available on-line for computing planetary magnitudes according to the equations and circumstances given in this paper. The files are posted as supplementary material for this paper. They are also available at SourceForge under project https://sourceforge.net/projects/planetary-magnitudes/ under the 'Files' tab in the folder 'Ap_Mag_Current_Version'.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
