* The Moon doesn't have a "dark side" The term "dark side" is misleading. Both sides of the Moon receive sunlight, just at different times. The side we see from Earth is called the "near side," and the side facing away is called the "far side."

* What we see depends on the phase: During the first and third quarter phases, we see exactly 50% of the Moon's surface illuminated.

* The "dark side" changes: Because the Moon rotates, different parts of the "far side" become illuminated during different lunar cycles. You never see the entire "far side" from Earth.

In short: You can't see any specific percentage of the "dark side" during the first and third quarter phases. You see 50% of the illuminated Moon, and that could include parts of the "near side" or "far side" depending on the specific time in the lunar cycle.