Retrograde motion
Retrograde motion is the apparent backward movement of a planet across the sky, as observed from Earth. This optical illusion occurs when Earth, traveling in its orbit, overtakes an outer planet like Mars, making the planet appear to reverse direction temporarily against the backdrop of stars.
Source: apod.nasa.gov
APODs including "Retrograde motion"
Saturn and Jupiter in Summer 2020
12/12/2020
During this northern summer Saturn and Jupiter were both near opposition, opposite the Sun in planet Earth's sky. Their paired retrograde motion, seen about every 20 years, is followed from 19 June through 28 August in this panoramic composite as they wander together between the stars in western Capricornus and eastern Sagittarius. But this December's skies find them drawing even closer together. Jupiter and Saturn are now close, bright celestial beacons in the west after sunset. On solstice day December 21 they will reach their magnificent 20 year Great Conjunction. Then the two largest worlds in the Solar System will appear in Earth's sky separated by only about 1/5 the apparent diameter of a Full Moon.