2019年IOAA理论第10题-南-东-北

来自astro-init

英文原题

South East North

Consider the Earth as a perfect, rigid, sphere with radius 𝑅=6378 km. There exist some points on the surface of the Earth from which we can travel first 6378 km South, then 6378 km East, and after that 6378 km North, and as a result return to the original point of departure. Find such points and paths. Calculate the geographic coordinates of the turning points of your solutions and draw the paths.

For the sake of simplicity measure the geographic longitude from 0° to +360° eastward from Greenwich, the geographic latitude from 0° to +90° north of the Equator and from 0° to −90° south of the Equator. Solutions resulting from rotational symmetry should not be considered to be different.


中文翻译

将地球考虑为半径为𝑅=6378 km的完美的刚性球体。在地球上存在一些点 符合以下条件:从该点向南走6378km,再向东走6378km,最后向北走6378km,就回到了出发点。找到这类点和路径。计算转向点的地理坐标并画出路径。

为了简化计算,我们从本初子午线向东,从0° 到 +360°计量经度。赤道为0°,向北至+90°,向南至-90°计量纬度。认为由旋转对称导出的结果没有区别。

官方解答