Did large meteor impacts cause volcanoes on the other side Mars?
Here's approximate locations for those regions indicating
a rough correlation as global opposites.

Largest Martian volcanic area
Tharsis-Olympus Mons region 240 E, 10 N
Largest Martian meteor impact
Hellas Impact Basin 70 E, 40 S

Next largest Martian volcanic area
Elysium Mons volcanic region 150 E, 25 N
Next largest Martian meteor impact
Argyre Impact Basin 320 E, 50 S

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