A few rules for the cleanroom where NASA’s new InSight Mars lander waits for launch. One, if you must sneeze, sneeze away from the spacecraft. Two, if you drop anything, let one of NASA’s escorts pick it up for you. Three, do not under any circumstances cross the black-and-yellow-striped tape and touch the spacecraft.

Oh also—an engineer tells a dozen media in a conference room at Vandenberg Air Force Base—do not lick the spacecraft. There’s always that one rebel, I suppose.

The InSight lander at rest in a cleanroom. NASA

The reasons to behave ourselves are many, and they are serious. For one, InSight costs nearly a billion dollars, and although it’s engineered to survive the punishing journey to Mars, it’s not engineered to be licked. And two, this conference room is loaded with planetary protection specialists, whose oh-no-big-deal job is to make sure Earthling microbes don’t end up colonizing Mars. And not just for the solar system’s sake—NASA is obligated by international treaty to keep other planets clean. In just a month, it'll fire InSight to the Red Planet, where the lander will drill to unravel the geological mysteries of our solar system's rocky bodies.

On Friday NASA shuffled us media into a pair of rooms designed to keep bugs the hell away from InSight. In the first, we step all over a sticky white rectangle, a kind of fly paper for particulates. Then we don those blue fabric booties you’d find in a hospital.

In the next room over, on goes the face mask, and over that a hood. A friendly yet stern specialist demonstrates how to step into coveralls without making any of the material touch the ground, or falling over and having to start all over again. Then I sit on a bench, feet on one side of a line of tape, and slide on shoes with high socks that cinch tight over my calfs. Only now can I swing my feet over to the other side of the tape—the clean zone.

The specialist ushers me through a glass door into a tiny closet dotted with vents, which blast my body as I spin 360 degrees with arms up. After a few seconds, I push through another door and into the planetary science version of heaven.

It’s shiny, almost entirely white, and cavernous. There sits InSight in two pieces—the spacecraft itself and the heat shield that’ll protect it from the 2,800-degree-Fahrenheit temperatures as it descends through the red planet’s atmosphere. Around it stand engineers in all white (media get conspicuous dark blue), hands clasped in front of them. I can see nothing but their eyes, but they’re friendly eyes. Eyes that say, What would you like to talk about at a safe distance from the spacecraft?