I believe the correct gravity on the moon is 1/6 of Earth.
Take note there is a difference between 1 6 and 1/6.
HOWEVER, we should realize that the trick here is that the
question asks about the MASS of the astronaut and not his weight. Mass is an
inherent property of an object, it is unaffected by external factors such as
gravity. What will change as the astronaut moves from Earth to the moon is his
weight, which has the formula: weight = mass times gravity.
Therefore if he has a mass of 50 kg on Earth, then he will
also have a mass of 50 kg on moon.
