The Apollo 11 moon landing of 1969 was an instantly iconic moment in world history. So, it can be easy to forget that Neil Armstrong, Buzz Aldrin, and Michael Collins were just fulfilling the duties of their job just like anyone on Earth — mundane tasks included.

In July 2015, Aldrin reminded us of that fact when he tweeted a photo of a forgotten souvenir from the journey: his travel voucher. The image outlines the unique points of travel: Houston, Texas > Cape Canaveral, Florida > Moon > Pacific Ocean (USS Hornett) > Hawaii > Houston, Texas. The grand total for reimbursement? Just $33.31 (for a rental car). Not bad for a round-trip ticket to the lunar surface. Anyone's guess if Aldrin was reimbursed in a timely manner.

In August 2015, Aldrin tweeted another photo of a fantastically ordinary piece of history from the trip: a customs form. All three of the Apollo 11 astronauts had to sign a customs form upon returning to Earth in Honolulu, Hawaii, on July 24, 1969. The document declared that the "cargo" they had brought back included "moon rock and moon dust samples." Also included on the form is a portion for "any other condition on board that may lead to the spread of disease." Answer: "TO BE DETERMINED."

But it wasn't all quite business as usual when the Apollo 11 astronauts came home from their multi-day jaunt on and around the moon. The three men were quarantined when they returned from the moon, just in case. And it wasn't just a short pit stop in the Mobile Quarantine Facility before heading back home; the astronauts were cooped up in there for 21 days. Hey, safety first, right?

The crews of Apollo 11, 12, and 14 were all quarantined, Robert Frost, Instructor and Flight Controller at NASA, explained on Quora. "[W]e didn't know that the Moon was sterile. We hadn't been there before, so how could we know? How could we know that there wasn't some form of life that could form and survive on a body like the Moon? How could we know that there weren't hibernating microorganisms in the lunar soil, just waiting to wake up and infect every living human, animal or plant on Earth?" said Frost. "To ensure we were taking safety seriously, we had to assume that there could be biological organisms in the samples returned and on the crew, their spacesuits and their vehicle, and we had to take reasonable measures to contain such life forms."

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Hear about everything Buzz Aldrin has learned in his life on Earth and elsewhere by picking up his book, "No Dream Is Too High: Life Lessons From a Man Who Walked on the Moon." We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.

For more fun stories from space, listen to our in-depth conversation with astronomer Michelle Nichols on the Curiosity Podcast. Stream or download the episode using the player below, or find it everywhere podcasts are found, including iTunes, Stitcher, and Gretta.