Ax-3 astronauts leave precious parting gift behind for ISS crew: peanut butter

A departing astronaut crew left behind a peanut butter surprise in space.

Ax-3, a four-astronaut mission leaving the International Space Station (ISS) aboard Crew Dragon "Freedom" from SpaceX, made a special call-out in the minutes after undocking at 9:20 a.m. EST (1320 GMT) earlier today (Feb. 7), on their way to returning to Earth two days later.

"There's some peanut butter waiting for you in the airlock entrance, on the forward side, enjoy" Ax-3 commander and retired NASA astronaut Michael López-Alegría told the Expedition 70 astronauts while backing away from the ISS, during a NASA Television broadcast. (The spacecraft was docked at the Harmony module's space-facing port side for a little over two weeks.)

While no full menu for Ax-3 is available, peanut butter has been a staple of astronaut preparation for decades. In fact, the Axiom Space private crew got to spend National Peanut Butter Day in space; that's an event each Jan. 24 marked by the U.S. Department of Agriculture's National Peanut Board, among other institutions.

Related: Live updates from the Ax-3 private astronaut mission

Ax-3 is the third crewed mission to the ISS organized by Houston-based Axiom, after two previous excursions in April 2022 and May 2023. For meal items, the company typically uses a food scientist to take "various commercial off-the-shelf food products" that will fare well in a floating environment with limited galley space, like "nutrition bars, candies, snacks and shelf-stable entrées", Axiom officials wrote in 2023.

But Axiom is far from the first to fly peanuts in space, as NASA astronauts at the least have snacked on them for generations. Cubes of peanuts are listed in the typical Gemini program menu, in the 1967 book "Lectures in Aerospace Medicine." And it appears that varieties of these cubes also flew to the moon with the Apollo 11 landing crew in 1969, per this picture from the Smithsonian Institution's National Air and Space Museum.

NASA space food specialist Paul Lachance spoke about these astronaut-friendly peanut cubes in a 1966 television program for the Massachusetts Institute for Technology, as Gemini was giving way to Apollo. "The bites we'd have are like the beef sandwich, which could also be a chicken sandwich, a cheese sandwich; compressed items, such as a peanut cube, which could also be a cereal cube of some sort; and even a fruit cake," he said.

Peanut butter, which may or may not be separate from these peanut cubes, apparently flew to the moon with Apollo astronauts in the 1960s and 1970s. It's mentioned both in the NASA 1999 document "Space Food and Nutrition", and a 2023 peer-reviewed study in the journal Life Sciences in Space Research.

But food preparation was limited in these little capsules, requiring astronauts to either eat it out of tubes or packets or to use a few squirts of water for preparation. The easiest varieties of travel food back then were powders or puddings, Lachance said in an oral history for NASA in 1996. (He died at age 83 in 2017.) "You could really take them off the shelf, and then just find a way to add the water and shake them up and make a pudding and then squeeze it out," he said.

Peanut butter was a staple of the shuttle program, which used a small galley for food preparation. It was in fact on board the very first mission, STS-1, in 1981 as this Smithsonian picture demonstrates. The savory spread continues to fly on ISS missions and sometimes shows up in astronaut videos, such as in Canadian Chris Hadfield's space cooking clips of 2012-2013 and NASA's Shane Kimbrough 2017 demonstration of peanut-butter-and-tortilla sandwich preparation in space.