2019年IOAA天文馆观测第3题

英文题目

PROBLEM 3 For this view, we are now standing on the Moon. At this instant viewed, the Earth is centrally eclipsing the Sun (see the red circle on the sky). Consequently the Moon is at one of its nodes now. Assume the longitudinal and latitudinal librations are exactly 0° at this moment.

QUESTIONS / TASKS:

3.1. At the time of this observation, which season is it in Hungary?

3.2. There is a yellow circle on the projected sky (next to the red circle), which denotes minor planet Juno, which is at a distance of exactly 3 au from the Sun at this moment. Estimate its distance to the Moon at this instant. (Rounded to the nearest integer in units of million km.) Assume all orbits to be circular.

3.3. Approximately how much time (in Earth days) after the projected event will …

…the Sun set at your observing site?

…the Earth set at your observing site?

3.4. Determine the Lunar (Selenographic) coordinates of this observing site (as defined in the lunar map on the next page):

What is the name of the large surface lunar area, where your observing site is situated? Do not use your national language, please use the official IAU nomenclature. (See lunar map on next page.)

3.5. Estimate the distance from the observing site to the Apollo-11 landing site (0.6875 N, 23.4333 E):

中文题目

问题3 从这个角度看，我们现在正站在月球上。在这一瞬间，地球与太阳形成中心食(见天空中的红色圆圈)。因此，月亮现在是在它的一个特殊点上。假设此时的纵向和纬向天平动都恰好为0°。

问题/任务:

3.1 在观测的时候，匈牙利是哪个季节?

3.2 投影的天空上有一个黄色的圆圈(在红色圆圈旁边)，表示 朱诺小行星，此时距离太阳正好3天文单位。估计其 此时距离月球的距离。(四舍五入到以百万公里为单位的最近整数。) 假设所有轨道都是正圆。

3.3 预计观测后大约有多少时间(以地球日计算)下列事件将发生：

太阳在你的观测点落下?

地球在你的观测点落下?

3.4 确定该观测点的月球坐标(见下一页月面图):

你的观测点所在的月海区域叫什么名字?请不要使用您的母语，请使用IAU官方命名法。 (见下一页月球地图)（事实上地图根本没有给月海名……这是道背诵题-小编注）

3.5 估算从观测点到阿波罗11号着陆点的距离(0.6875 N，23.4333 E):