元旦,在《数理天地》网站上读了一篇文章《月球上为什么没有大气》,其大意为: 气体分子做剧烈的热运动,如0℃,一标准大气压下N2、O2分子运动的平均速率为454m/s、425m/s.而月球的第二宇宙速度(脱离速度)仅为2360m/s,于是在不太高的温度下,气体分子很容易达到这一速度而脱离月球.月球可能曾经拥有大气,只是因为引力小吸 On New Year’s Day, an article was read on the website of “Mathematics and Planetary World”, “Why is there no atmosphere on the Moon?”, the general idea is: The gas molecules do intense thermal movement, such as 0°C, the average rate of N2, O2 molecular motion at a standard atmospheric pressure At 454m/s, 425m/s. While the moon’s second cosmic velocity (disengagement velocity) is only 2360m/s, at very low temperatures, gas molecules can easily reach this speed and escape the Moon. The Moon may have Have atmosphere, just because of gravity