Astronauts brought back a total of 842 lbs (382 kg) samples of lunar rocks and soil over the course of six missions
. International teams of scientists - both affiliated and unaffiliated with NASA - have analyzed these samples and have determined that the rocks are not of terrestrial origin
. The rocks, identified as mostly basalts and breccias, have chemical makeups that are very different from those found on earth
. They are also estimated to be up to 4.5 billion years old; the oldest earth rocks are approximately 4.28 billion years old
, which is a 200-million-year difference.
With the technology available in the 1960s, it would not have been possible to organize an unmanned sample-returning mission. In fact, NASA has yet to successfully complete an unmanned sample-returning mission to and from a planetary surface
Apollo missions 11, 14, and 15 left mirrors, called laser-ranging retroreflectors, on the moon's surface. High-powered laser beams can be aimed through telescopes; the reflection of the beam bounces off of the mirrors and is returned to earth
. This ongoing experiment is meant to provide data on the distance between the moon and earth but also serves as physical evidence that the moon landings were not fake.
Lastly, photographs taken by the Lunar Reconnaissance Orbiter mission in 2009 show the remainders of physical evidence left by astronauts on the moon, such as footpaths, landing sites, and various scientific instruments
. The abundance of physical evidence that NASA has collected over the decades is enough proof to confirm the moon landing was real, and humans have stood on the moon.