When Mars becomes retrograde, it enters the retrograde zone and it starts to slow down. It starts moving in the backward direction before becoming stationary and keeps on moving in the forward direction in the retarded speed. It is known that Mars remains in the stationary position for a time being before it starts to move in the backward direction. The time at which Mars starts to move in the backward direction is important and is noted down for the calculations.
2021 Mars Retrograde Motion
When Mars becomes progressive, the same phenomenon occurs i.e., the time when Mars starts to move in the forward direction. Till it gains full speed, it remains in the retrograde zone before moving in the forward direction. The time at which Mars starts to move in the forward direction is important and is noted down for the calculations.
To sum up all, there are four points in each retrograde zone i.e., Retro Station, Shadow, Direct Station and Release.