Final answer:
A surface must be smooth compared to the wavelength of light, with irregularities smaller than a few hundred nanometers, to produce specular reflection. The 'fine and powdery' lunar surface, marked by astronaut bootprints, does not meet this standard as it causes diffused reflection due to its roughness and texture.
Step-by-step explanation:
For a surface to produce specular reflection, it must be smooth in comparison to the wavelength of light. This means any irregularities on the surface must be smaller than approximately a few hundred nanometers. Mirror-like reflections are observed when light reflects off such smooth surfaces at specific angles, highlighting features like the image in a mirror.
According to Neil Armstrong's description during the Apollo 11 mission, the Moon's surface is 'fine and powdery,' allowing astronauts to leave bootprints in the lunar soil. These bootprints are a clear sign that the lunar surface has significant texture and irregularities at a scale much larger than the wavelength of visible light, thus not meeting the standard for producing specular reflection. Instead, the lunar surface scatters light in many directions due to its roughness, resulting in diffused reflection.
The fact that lunar soil is porous and has an extreme temperature variation also indicates its surface roughness and textured nature. While some areas of the Moon may reflect light to form a glint or sheen due to smaller smooth patches, overall, the bootprints left by astronauts on the Moon confirm that the lunar surface is not smooth enough for specular reflection on a large scale.