While no confirmed “secrets” from the dark side of the moon have been revealed by an Apollo 11 astronaut, the Apollo 8 mission, which orbited the moon in 1968, became the first to see the far side, and the Apollo 11 mission collected samples that included evidence of an early “magma ocean”.

Here’s a more detailed breakdown:
Apollo 8’s View:
The Apollo 8 astronauts were the first humans to see the far side of the moon, describing it as “a sand pile my kids have played in for some time. It’s all beat up, no definition, just a lot of bumps and holes”.

Apollo 11’s Samples:
The Apollo 11 mission primarily collected basalts and breccias, but fragments of the Moon’s highland crust found in some of the breccias provided evidence of an early “magma ocean”.
No Human Footfall on Far Side:
No human has set foot on the far side of the moon, and no unmanned craft landed there until 2019.

Chang’e-5 Samples:
The Chinese Chang’e-5 mission also brought samples from the far side, which primarily consisted of basalt, breccia, agglutinate, glᴀsses, and leucocrate.
“Dark Side” Misnomer:
The term “dark side” is a misnomer, as the far side of the moon is actually brighter than the near side, and the phrase is often used to refer to something mysterious or unknown.