There is no atmosphere on the Moon, because

There is no atmosphere on the Moon because its escape velocity is less than the root mean square velocity of atoms; option [D]. This means that gas molecules on the Moon can easily escape into space due to insufficient gravitational pull. Consequently, over time, the Moon lost its atmosphere, resulting in its current lack of significant atmospheric gases. This phenomenon contrasts with Earth, which has a sufficiently strong gravitational pull to retain its atmosphere. The Moon’s proximity to the Earth or its revolution around the Sun doesn’t directly affect its lack of atmosphere. While sunlight does reach the Moon, the absence of a significant atmosphere prevents it from creating conditions conducive to atmospheric processes like those on Earth. Therefore, the correct option is [D] Here the escape velocity of atoms is less than their root mean square velocity, elucidating the fundamental reason for the Moon’s lack of atmosphere.