Venus and Mercury Trails

Honorable mention in the 2023 IAU OAE Astrophotography Contest, category Still images of phases of Venus: Venus and Mercury Trails, by Marcella Giulia Pace.

In this composite image, both Mercury (left) and Venus (right) can be seen heading into the sunset. The phases of each are beautifully captured as they descend. Not all planets or moons in the Solar System show phases as viewed from Earth. This phenomenon occurs because the orbits of Venus and Mercury are positioned between Earth’s orbit and the Sun, sometimes allowing us to see only part of the illuminated portion of each planet. These phases are similar to the phases we see of our own Moon.

Credit: Marcella Giulia Pace (CC BY 4.0)