Answer:
there are a couple reasons
they would be able to hear outside there suits i believe also gravity is light on the moon so rocks would likely fall softly where they would notice also landslide would be very rare on the moon due to the material the moon i s made of which would moves do to impact and there are a lot of reasons that anyone could make up
Step-by-step explanation:
but the scientific answer is : sound waves needs a medium to travel just like our planet, we are able to hear each other because the air around us acts as the medium which sound waves travel, however, the moon does not have any air that sound waves,which a landslide would produce, use to travel from one place to another.