Neil Armstrong left his wife Carol a doozy of a surprise in his closet—an otherwise unremarkable white storage bag full of equipment he carried to the moon and back. The family of the late astronaut has donated the "McDivitt Purse" and its contents to the Smithsonian.

After his historic trip to the moon, Armstrong apparently hung onto the mission's Temporary Stowage Bag, which contained a 16mm Data Acquisition Camera used to film the late astronaut's famous first steps on the lunar surface, two waist tethers intended for emergency spacewalks, and more. Those bags were informally called McDivitt Purses by Apollo astronauts because they were the brainchild of Apollo 9 Commander James McDivitt. Such bags were used clipped into sockets in front of the Commander's station in the Apollo program's lunar module, and used to stuff odds and ends when there wasn't time to put them back in their permanent storage locations.

Armstrong died in August 2012, leaving behind personal effects such as his correspondence, which his family donated to Purdue University, the astronaut's alma mater, as well as other items donated to the National Collection. But he apparently kept his possession of the McDivitt Purse a secret, according to Allan Needel, a curator in the Space History Department of the Smithsonian's National Air and Space Museum.

When Carol Armstrong sent a photo of the bag and its contents to Needel and his colleagues, they found it "hard to imagine anything more exciting."

"Realizing how important it would be to determine whether any or all of these items were actually flown in the Lunar Module Eagle during the historic Apollo 11 mission, I decided to enlist the expertise of Eric Jones, Ken Glover, and the team of experts who have put together the incredible Apollo Lunar Surface Journal (ALSJ) website, an indispensable site of detailed information about all aspects of the Apollo program," Needel said.

The ALSJ team determined with "almost complete certainty" that the items in Armstrong's Temporary Stowage Bag had made the trip to the moon in the Eagle. The Apollo 11 mission actually called for Armstrong to leave those items in the lunar module, which crashed to the moon's surface after detaching from the command module which carried Armstrong, Buzz Aldrin, and Michael Collins back to Earth.

Armstrong, Aldrin, and Collins apparently had other ideas and managed to keep his possession of some remarkable Apollo 11 artifacts a secret from most everybody for 45 years—though a review of the Eagle mission transcript record gave a pretty big clue as to their plans for the McDivitt Purse and its contents.

"Less than an hour before they were ready to jettison Eagle, mission transcripts record Armstrong saying to Collins (Mission Elapsed Time (MET): 129:14:53): 'You know, that—that one's just a bunch of trash that we want to take back—LM parts, odds and ends, and it won't stay closed by itself. We'll have to figure something out for it'," Needel noted.

The National Air and Space Museum is now displaying the camera and spacewalk tethers in its temporary exhibit, Outside the Spacecraft: 50 Years of Extra-Vehicular Activity.