Mars Retrograde Happens Every Two Years
As seen from the Earth(observer), the planets don't always make steady progress along the ecliptic(Path of the planets). They usually move in the same direction as the Sun (i.e., eastward), but from time to time they seem to slow down, stop, and reverse direction (i.e., move westward). This apparent reversal is called retrograde motion.
Apparent retrograde motion occurs when the observer (Earth) and the retrograding object (e.g., Mars) align with the Sun. Retrograde motion is an illusion created when we observe other planets from the moving planet Earth.
<u>Example:</u>
A familiar example of retrograde motion occurs when you pass a car on the freeway, the car being passed appears to move backwards relative to you.
For the planet mars, it takes almost two years to observe this kind of motion.
To know more about mars retrograde motion kindly refer to the below link:
brainly.com/question/12016093
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