Final answer:
An astronaut weighing 254 lbs on Earth would weigh about 42.33 lbs on the Moon and about 84.67 lbs on Mars, as the gravitational force on the Moon is 1/6th and on Mars is 1/3rd of that on Earth.
Step-by-step explanation:
The question is regarding the weight of an astronaut on different celestial bodies, specifically the moon and mars. Weight is the force of gravity acting on an object and depends on the local gravitational acceleration. Mass, however, is a measure of the amount of matter in an object and is constant regardless of location. On the Moon, where gravity is about 1/6th of Earth's, the astronaut's weight would be 1/6 of the weight on Earth. On Mars, with gravity about 1/3rd of Earth's, the astronaut's weight would be 1/3 of the weight on Earth.
An astronaut weighing 254 lbs on Earth would weigh approximately 42.33 lbs on the Moon (254 lbs / 6) and approximately 84.67 lbs on Mars (254 lbs / 3).