The International Space Station. Send Clorox.

I’ve been attending some of the sessions at the Humans to Mars summit the last couple of days (for full coverage check out Jeff Faust’s Foust’s space politics blog), and here’s one takeaway: Real spaceflight is very different from PowerPoint spaceflight (borrowing a truism here from former NASA boss Mike Griffin).

Case in point: At a session yesterday, Bas Lansdorp, the head of a nonprofit organization called Mars One, discussed his extraordinarily ambitious plans for a permanent Mars colony starting in 2023. The idea is to make a reality TV show out of it, in which different teams will compete for the honor of becoming the first Martian colonists (the audience will vote, as will “experts,” Lansdorp said). Hardware would be flown to Mars and landed on the surface to await the first humans, with four astronauts arriving in the first wave, in April 2023, then four more two years later. They will all have to commit themselves to being on Mars for the rest of their lives. Let’s move beyond the obvious issue of whether this scheme is, in the literal sense, fantastic. Or even ethical. Today I just want to note that one of Lansdorp’s slides showed the Mars One living quarters on Mars: Very spacious, modern, and most of all, clean.

No clutter. No stacks of newspapers piling up in the corner. No empty beer glasses or leftover pizza. Life on Mars looks like life in a nice room at the Ritz.

“You can see it’s quite a nice living volume for them to live in,” Lansdorp said. “It’s important for them to have a nice place to live bcause this is their home. This is where they are staying the rest of their lives.”

But then came the other panelists, including engineers who work on space flight. There was a lot of talk about dust. Turns out, Mars is really dusty, and a major challenge would be keeping the dust out of the habitat and particularly out of the airlock, which could cease to be operational or safe if too contaminated with dust.

And there was an astonishing pair of images, presented by a fellow from Boeing, Greg Gentry, who has duties involving the International Space Station (I didn’t quite catch his precise role). He showed the U.S. laboratory module at launch: A perfectly clean chamber, with all the equipment carefully stowed in cabinets — not a loose item to be seen. Then he showed that same module as it is actually used at the International Space Station: Extremely cluttered, with wires everywhere, gear all over the place. Frankly, it looks like a mess (though I’m sure the astronauts know exactly where everything is and why they’ve got it set up that way).

“We really didn’t anticipate the needs for stowage very well,” Gentry said.

The ancient lament: Not enough closet space!

Moreover, much of space flight involves maintenance, which is to say, cleaning filters. Scuzz gets into the filters like you wouldn’t believe. Lint invades devices that were never designed to be cleaned. Mysterious substances form — like little wafers of zinc oxide, origin unknown, forming in one of the filtration systems. Biofilms grow. And even with a 6 person crew on the station, they spend so much time doing maintenance and repairs, “we are happy when we get 30 hours of science out of the crew a week,” Gentry said.

Funny: The visionaries never have PowerPoint slides showing astronauts scrubbing filters.