Look up: Mercury is at its farthest distance from the sun on Aug. 19

August is full of celestial events, and this week marks a milestone for the 4.503 billion-year-old planet known as Mercury.

Being such a small planet that lies close to the sun, Mercury can be difficult to see. That’ll change on Aug. 19, when planet-gazers on Earth can look up and see Mercury at its greatest distance from the sun, according to Time and Date .