On the internet, you need to be a skeptical reader these days. Claims of aliens and UFOs, Mars being abnormally big, or the moon turning green are the kinds of things you should check out carefully. Here are some of the biggest space myths that just won’t go away.

NASA

Twelve NASA astronauts walked on the moon between 1969 and 1972, and the Lunar Reconnaissance Orbiter has since released new photos of the landing sites. In the decades since Apollo 11 astronauts first set foot on the moon, many theories have been put forward claiming that the whole Apollo program was staged. Why are there no stars in the sky in the moonwalkers’ photos? Why are the U.S. flags fluttering on the surface? Why do you see footprints in the pictures, but no marks from the lunar modules that landed there?

The answers to those questions are simpler than you may think. There are no stars in the sky for the same reason you don’t see stars during the day on Earth: The bright glow of daylight on the surface washes them out. U.S. flags planted into the lunar soil had metal rods sewn in them to appear as though they were moving. Without these wires, the flag would have hung straight down, making for a pretty lackluster photo prop. And the lunar modules, though heavier, didn’t put prominent marks in the surface in some places because their mass was more evenly distributed than the astronauts’ weight was in their boots.>>>>READ MORE