無氧氣瓶沒宇航服太空漫步，恐怕最震撼的是太空人本人
月球是一個圍繞地球運行的天體，是地球唯一的永久性天然衛星。 它是太陽系中第五大天然衛星，並且相對於它所環繞的行星的大小而言是行星衛星中最大的。 在已知密度的衛星中，月球是密度第二高的天然衛星，僅次於木星的衛星 Io。
月球的直徑約為 3,474 公里（2,159 英里），約為地球質量的 1/81。 它平均距離地球約 238,855 英里（384,400 公里）。 月球表面佈滿岩石和塵土飛揚，有許多撞擊坑和其他特徵，如山脈、山谷和平坦、黑暗的平原，稱為“瑪麗亞”（拉丁語意為“海洋”）。 月球沒有大氣層，也沒有水，並且由於沒有氣體保護層來保持熱量，所以它會經歷極端的溫度變化。
月相（滿月、新月、盈月和虧月）是由月球圍繞地球的軌道及其反射陽光的方式引起的。 長期以來，月相對人類很重要，月球在世界各地的許多文化和傳統中都發揮著重要作用。
The Moon is an astronomical body that orbits Earth and is Earth’s only permanent natural satellite. It is the fifth-largest natural satellite in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits. The Moon is the second densest natural satellite among those whose densities are known, after Jupiter’s moon Io.
The Moon has a diameter of about 3,474 kilometers (2,159 miles) and is about 1/81 the mass of Earth. It is approximately 238,855 miles (384,400 kilometers) away from Earth on average. The Moon’s surface is rocky and dusty, and it is marked by numerous impact craters and other features such as mountains, valleys, and flat, dark plains called “maria” (meaning “seas” in Latin). The Moon has no atmosphere and no water, and it experiences extreme temperature variations because it has no protective layer of gases to retain heat.
The Moon’s phases (full, new, waxing, and waning) are caused by the Moon’s orbit around Earth and the way it reflects sunlight. The phases of the Moon have long been important to humans, and the Moon has played a significant role in many cultures and traditions around the world.
