Question

The work done by a weightless piston in causing an expansion ∆V ( at constant
temperature ), when the opposing pressure, P is variable, is given by:​

Answer 1

During the sunrise the sun is set close to the Earth's horizon, and therefore light travels a longer distance through the atmosphere of the Earth.

During the sunrise the sun is set close to the Earth's horizon, and therefore light travels a longer distance through the atmosphere of the Earth. This is the reason sun appear reddish early in the morning. The astronaut will not observe this phenomenon on the moon's surface, because the moon has no atmosphere.