Apollo 17 Command Module, and a porthole view of an astronaut strolling on the moon.

Space Center Houston

Houston, Texas

The faint -- we're talking molecular level -- sweat from hundreds of hard-working astronauts lingers on artifacts at Space Center Houston, the exhibition airlock between earthbound tourists and Johnson Space Center, which is the training base for all NASA and ISS astronauts. "What we have are things that relate to human spaceflight," said Carmina Mortillaro, a Center exhibit specialist. "The real things." That's true: pretty much everything at Space Center Houston was either touched by, sat on, or protectively cocooned a real astronaut.

International Space Station replica hangs from the rafters in the Main Plaza.

There are, for example, the well-travelled spacecraft from Mercury 9 (1963), Gemini 5 (1965), and Apollo 17 (1972), all dramatically staged with their interiors aglow. There are the Space Shuttle's two ejection seats, which were removed at astronaut request from the Shuttle after its crew increased to seven with no way of ejecting the other five. Pete Conrad's Apollo 12 moon suit is here as well, still caked with 1969 lunar dust in its sealed display capsule.

Another highlight of Space Center Houston is the Crew Access Arm, the formerly sky-high walkway between the launch tower and rocket ships from Apollo to the Space Shuttle. It may be the only space relic that the public is allowed to walk on. Carmina told us that visitors can "follow in the footsteps of astronauts," but when we asked if NASA planned to paint famous astronaut footprints on it, she laughed.

World's only piggyback Space Shuttle display features a walk-thru Orbiter and 747.

"No, because it's an actual artifact."

Space Center Houston is home to a number of the now-historic training mockups formerly used at JSC, the best surviving examples of habitats, craft, and vehicles that have since been lost in space, such as the Lunar Lander and Lunar Rover. Especially impressive and unexpected is a full-size Skylab, America's first space station, which is so large that the Space Center had to be built around it. That NASA would save something this big -- a full-size fake antique space station -- is as impressive as the thing itself. In contrast to the immense mockup, Space Center Houston also displays a tiny, frayed fragment of the real Skylab, one of the few pieces that survived its fiery reentry in 1979.

The Lunar Touchstone has to be periodically cleaned of Earth finger grease.

Moon rocks are the most famous things touched by astronauts, and Space Center Houston houses the largest collection anywhere on display, chosen, said Carmina, to showcase the moon's diverse geology. The rocks are inside a clean room replica of the lunar lab at JSC, which is itself inside The Lunar Vault with a giant steel door. In the center of the vault is the Lunar Touchstone, displayed in a case where visitors can insert their hands and put one finger on the rock. "We cleaned the Touchstone a couple of years ago," said Carmina (Earth fingers are dirty). "More than 20 million people have come through here, and I would say most everybody touches that rock."

Historic Mission Control was fully restored in time for the 50th anniversary of the moon landing.

Out in front of Space Center Houston, performing the same "Hey, over here!" function as a dinosaur by the highway, is a scorched, 156-foot-long SpaceX Falcon 9 rocket that flew to the International Space Station twice and landed back on earth each time (it was installed here in 2020), and the world's only piggyback Space Shuttle. Space Center Houston was shocked when it was denied one of the retired Shuttles, but turned lemons into Tang-flavored lemonade by acquiring the mockup Shuttle from the Kennedy Space Center (which received a real Shuttle) and mounting it atop one of the 747s that routinely flew the spacecraft from California to Florida. Visitors can now tour the 747, full of displays about its unique job, then climb and walk through the Shuttle. Space Center Houston points out that you can't go inside any of the four real Shuttles, but you can go inside this one.

Visitors peer into the dizzying full-size Skylab mockup.

Also unique to Space Center Houston are its tram tours, which take visitors onto the JSC campus, either to Historic Mission Control (made famous by Apollo 11 and the movie Apollo 13) or to Building 9, where visitors can walk an elevated gallery overlooking the training mockups currently used for the International Space Station and Mars Orion mission. Both trams stop at Rocket Park with its Saturn V moon rocket, 363 feet long, the largest of Space Center Houston's supersized showstoppers. A special "Level 9" VIP tour also takes visitors to the Neutral Buoyancy Lab, which is a pool filled with 6.2 million gallons of water, big enough to submerge the mockup Skylab and ISS.

We asked Carmina if she's ever met a space question she couldn't answer. "We've had some people coming here asking where the Zero Gravity Room is," she said. "We have to explain to them that you can only get Zero Gravity in space; you can't make it on Earth" (Although that hasn't stopped some Earthlings from trying).

Perhaps the most undeservedly overlooked heroes at the Johnson Space Center are its Space Food Systems Laboratory biochemists, who gave the world freeze-dried astronaut ice cream. Carmina told us that it's still one of the most popular items in the Space Center Houston gift shop.