摘要或動機

In this project, we mainly employ the self-made “positioning system for celestial objects” (PSFCO) to investigate the relations among Sun, Moon, and Earth. Based on the observational data, we then construct a three-dimensional (3D) model to further understand the hidden mystery. We first use the PSFCO, which was developed through four generations (see figure 1), to measure the change for a whole year in the North Polar Distance (NPD) of Sun and Moon individually. From the data analysis, we find that: 1. This change in NPD is very close to a sinusoidal function. 2. The date when the NPD of Moon is the largest in a month shifts earlier by 2.26 days every month on average. 3. The angle between the equatorial axis (EA) and the lunar orbital plane (LOP) is about 63.5 degrees, while the angle between the EA and the ecliptic plane (EP) is about 66.5 degrees. 4. The angle between the LOP and the EP is about 5 degrees. This is exactly why the solar eclipse and the lunar eclipse do not happen every month. 5. Time for a celestial object to be above the horizon = 1080 minutes – 4 (minute/degree) x NPD of the object. We geographically prove this empirical formula. With this formula and the PSFCO, we can accurately predict the times when an object rises and sets. We finally make a 3D model for Sun, Moon, and Earth. In this process, we confronted and then solved several difficult questions in mathematics and astronomy. This research dramatically enhances our understanding in our local planetary system. 主要利用自製的“天體定位儀”來詳細探討月亮、太陽及地球之間的位置及軌道關 係，並藉由三度空間模型的製作來進一步了解其中的奧妙。 首先利用天體定位儀 (共研發出四代，見圖1) 來量測月亮及太陽各自與北極的夾角 在1 年內的變化，經數據分析發現： 一、這個變化很像sin 函數。 二、月亮與北極的夾角發生極大值的農曆日數，每月平均提早約2.26 日。 三、白道面與赤道軸的夾角約為63.5 度，黃道面與赤道軸的夾角約為66.5 度。 四、白道面與黃道面之間的夾角約為5 度。這正是日蝕及月蝕不常發生的主要原因。 五、天體在地平線上的時間(分) = 1080 分－４(分/度) x 天體與北極夾角(度)。我們用幾 何定理證明了這個觀測到的關係式，且配合天體定位儀可準確預測任何可見天體 升上及落下地平線的時間。 最後製作月亮、太陽及地球的3D 軌道模型。過程中遭遇並解決了各種數學及天文 難題，使我們對這個行星系統有了更深一層的認識。