Since the moon doesn’t have an atmosphere, there’s no wind or water to erode or wash away the Apollo astronauts’ mark on the moon. That means their footprints, roverprints, spaceship prints, and discarded materials will stay preserved on the moon for a very long time.
They won’t stay on there forever, though. The moon still a dynamic environment. It’s actually being constantly bombarded with “micrometeorites,” which means that erosion is still happening on the moon, just very slowly.
Source: Space.com

Neutron stars are one of the possible evolutionary end-points of high mass stars. They’re born in a core-collapse supernova star explosion and subsequently rotate extremely rapidly as a consequence of their physics. Neutron stars can rotate up to 60 times per second after born. Under special circumstances, this rate can increase to more than 600 times per second.
Source: Swinburne University of Technology Centre for Astrophysics and Supercomputing