Question

Julian is using a biking app that compares his position to a simulated biker traveling Julian's target speed.
Julian sets the simulated biker to a speed of 20 km/h. After he rides his bike for 15 minutes, Julians app reports a position of -2 1/4 km whats has julians averge speed been so far

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.

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.