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Mars Retrograde Motion

-- Kathy | April 17, 2025

Question:

Am wondering why Mars looks like it’s moving backwards in relation to where it was several weeks ago. (Mars formed a triangle with Castor and Pollux, and before that was in line with them.) Now it looks like Mars has moved back to be somewhat in line with the two stars again. I don’t understand how that can happen. I would so appreciate if you could help me understand what is happening. Am just a amateur star gazer and am so confused. Thank you.

-- Kathy

Answer:

I believe what you are seeing is the apparent “retrograde”, or backwards, motion of Mars as the Earth overtakes Mars on an inside track (orbit) around the Sun. Mars was most recently in an apparent retrograde motion in the sky from December 6, 2024 until February 23, 2025.

-- Jeff Mangum

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