Observing Mars' Loop Normally, watching a planet go through its retrograde motion would take several months of nightly observation and require carefully plotting the planets position every night. Fortunately, Stellarium can simulate several months' worth of motion in just a few minutes. Execute the following commands. Start Stellarium. Turn off Ground, Atmosphere and Fog by Pressing G, A and F. To view Ecliptic line, go to Sky and Viewing options window, select the fourth tab "Markings" and check on "Ecliptic J2000". Close Sky and Viewing options window. Press the shortcut C and V to show constellation lines and labels 'Show Lines' and 'Show Labels'. Go to the search tab on the lift and type 'Mars' and press [space] to center it, Press F11 for full screen mode