Final answer:
An astronaut's mass remains constant between Earth and the Moon, but her weight changes due to the differences in gravity. Human space exploration has arguments for and against it, involving costs, risks, and benefits. Lack of stars in Moon landing photos is due to camera settings, not a faked landing.
Step-by-step explanation:
The mass of an astronaut does not change when she travels from Earth to the Moon, because mass is a measure of the amount of matter in an object and is constant regardless of location. However, her weight does change due to the different gravitational forces on the Moon compared to Earth. The Moon's gravity is about 1/6th that of Earth's, so an astronaut would weigh significantly less on the Moon.
One could argue for continued human exploration of space, putting forward various arguments and facts such as the pursuit of scientific knowledge, the need for a backup plan for humanity, and the inspirational aspect of space exploration. Conversely, arguments against it might include the high cost, the risks involved, and the fact that robotic explorers can often accomplish the necessary tasks at a lower risk and cost.
Regarding the Moon landings and why no stars are visible in photos, it's pivotal to understand that the camera settings used to photograph the brightly-lit lunar surface are not sensitive enough to capture the relatively dim stars in the background. This phenomenon is similar to not seeing stars in daytime photos on Earth.