When one of humanity’s cosmic explorers discovers something unexpected, it is always fantastic. This time, it’s the European Space Agency’s Mars Express’ chance to catch a glimpse of an uncommon occurrence. After over 20 years of watching the Red Planet, the orbiting spacecraft has recently recorded an astronomical occultation. A view of Deimos, one of Mars’ two smaller moons, was captured when it passed in front of Jupiter and its four largest satellites.
Deimos exactly passed in front of Jupiter, Io, Callisto, Europa, Ganymede, and the four Galilean moons on February 14, 2022. Scientists learned a lot about Deimos’ orbit thanks to a chance alignment between the 15-kilometer (less than 10-mile) Martian moon and the far-off Jovian system.
This insight is crucial because it helps us better understand how the martian moons behave. While Deimos’ larger companion Phobos is approaching Mars, Deimos is going away. Phobos may give mars a ring and may finally be annihilated by the gravity of the Red Planet.
Deimos’ apparent up-and-down motion is a result of the spacecraft’s vibrating solar wings and radar antenna. In addition, image processing and enhancement were the only things that made the Jovian moons visible. Without it, the background would have been completely illuminated by Jupiter’s light. The brightest planet is the king of the planets (check it out in the sky tonight, towards the south in the Northern hemisphere.)