Caption: Pete Conrad (1930--1999) of Apollo 12 (Apollo 12 Nov20) on the Moon finds Surveyor 3 (landing date 1967 Apr17).

Notice the regolith dust. This powdery dust has been created by blasting by micrometeoroids and other space weathering processes. The dust (NOT the regolith in toto) is perhaps a few centimeters thick (Se-445). The dust is quite glassy and slippery (Ze2002-177).

The Apollo astronauts always landed in the daytime of the lunar day, but the sky looks black because there is almost NO atmosphere to scatter sunlight around.

Airless worlds are astro-bodies NO or almost NO atmosphere. A very thin atmosphere where atoms and molecules are gravitationally bound to a astro-body, but have too low a density to collide with each other significantly is called an exosphere. There is, in fact, a lunar exosphere: i.e., Moon's atmosphere.

Recall the lunar day is as long as the lunar month = 29.530588861 days (mean value, J2000) and so lunar daytime is about 14.7 days.

Because of the Moon's small size the horizon seems very near. Perhaps this is NOT obvious in images, but the Apollo astronauts were quite struck by it (PF-103).

To explicate the distance to the horizon, consider the horizon distance formula:

  d = (2hR+h**2)**(1/2) = (2hR)**2*[1+h/(2R)]**(1/2)  
       where h is height and R is sphere radius

    = (2hR)**2*[1++h/(4R)+ ... ]

    =  3.5715926*[h_m*(R/R_⊕_eq)]**(1/2) to 1st order in small h/R

    ≅ 3.571 km   for h_m = 1 and R = R_⊕_eq = 6378.1370 km
    ≅ 5.051 km   for h_m = 2 and R = R_⊕_eq = 6378.1370 km
    ≅ 2.637 km   for h_m = 2 and R = R_☽_eq = 1738.14 km.  

Credit/Permission: NASA, NASA: Catalog of Spaceborne Imaging: Astronaut Pete Conrad inspects the Surveyor 3 spacecraft on the Moon, 1969 / Public domain.
Image link: Itself.
Local file: local link: moon_regolith_pete_conrad.html.
File: Moon geology file: moon_regolith_pete_conrad.html.