Final answer:
An astronaut's mass remains the same during orbit, but their weight decreases due to the microgravity environment that causes a state of continuous free-fall.
Step-by-step explanation:
How Do Mass and Weight Change from Earth to Orbit?
When an astronaut leaves Earth's surface and begins orbiting Earth, their mass remains unchanged since it is an intrinsic property of the matter that constitutes their body. However, their weight, which is a measure of the force exerted on their mass by gravity, will decrease due to being in a state of free-fall during orbit. This can be explained because in orbit, astronauts experience what is known as 'microgravity' or 'weightlessness,' although there is still gravity acting on them, it's just that they are falling towards Earth at the same rate as the spacecraft, creating the sensation of weightlessness.
In summary, the correct option in regards to how an astronaut's departure from Earth affects their mass and weight is: Option 1: Mass remains the same, but weight decreases. This is because mass is a measure of the amount of matter in an object and does not change regardless of location, whereas weight depends on gravitational pull which changes with location.