What a difference the time of day makes on the moon.
NASA’s Lunar Reconnaissance Orbiter has re-photographed the Apollo 11 landing site on the Sea of Tranquility. The first picture released on July 17 showed the long shadow of the lander because the sun was low in the sky. It was essentially late afternoon on the moon.
In the new picture the afternoon sun is 28 degrees above the horizon and the site looks noticeably different with better contrast and brightness.
In particular, you can see the trail of footprints of the first man on the moon, Neil Armstrong, as he walked to the 100-foot wide Little West crater for a close-up look.
The astronauts’ footpath to the TV camera is visible as well as the camera itself. Two parts of the Apollo Lunar Science Experiments Package (ALSEP) stand out - the Lunar Ranging Retro Reflector (LRRR) and the Passive Seismic Experiment (PSE).
I like this picture because the Apollo hardware is clearly evident as bright artifacts on the lunar surface. The linear footprint trails clearly cannot be explained by natural processes. But it is humbling to see how insignificant everything looks against the vast lunar wasteland.
Unevolved moons and asteroids in the solar system could be littered with undetected artifacts left behind by visits from extraterrestrial probes over geologic time. But this kind of view tells me that alien artifacts could only be detected in high-resolution photo surveys. That is, assuming they were built on the scale of the Apollo hardware. This seem reasonable becasue a small probe would be far less costly to propel across interstellar space than something massive.