IT·Science Talk

Honest question: why go to a moon of Mars instead of Mars itself?

Doctor, not a space person, so be gentle. Japan's MMX is going to land on Phobos and bring back about 10 grams of dust in 2031. Meanwhile, according to the GONOM article, NASA's own Mars return plan was effectively cancelled, and China is going for Mars itself with Tianwen-3.

So why Phobos? Is it just easier to land on and leave because the gravity is tiny? Or is there something scientifically special about it? And would dust from Phobos tell us anything about Mars, or only about Phobos?