This is the 1516th most frequent Russian word.
поверхности
"Surfaces" or "of the surface" (depending on context).
In this sentence, 'поверхности' refers to the flat area of a physical object, specifically the table top.
На поверхности стола лежала книга.
A book lay on the surface of the table.
Here, 'поверхности' is used in plural to describe different exposed areas of the moon.
Поверхности луны изучаются учёными во всём мире.
The surfaces of the moon are studied by scientists all over the world.
In this case, 'поверхности' specifies the external visible area of a structure.