Just a guess: The weaker gravity (around 1/3 of Earth's gravity) makes it much easier for wind to pick dust off the ground. Once a dust storm starts, it would a

Just a guess: The weaker gravity (around 1/3 of Earth's gravity) makes it much easier for wind to pick dust off the ground. Once a dust storm starts, it would also take a lot longer for the cloud of dust to dissipate. Look at the videos of astronauts on the moon from the Apollo landings. Everything they do kicks up a significant amount of dust that takes quite a while to dissipate. Obviously it's not a perfect comparison because the moon has weaker gravity and a different composition.