HUNTSVILLE, Alabama - I've just moved from the "dirty" side of the bench to the "clean" side by pulling a thin paper cover onto one shoe while facing the "dirty" side, swiveling and putting that foot on the floor on the "clean" side.

It seems a little silly. I'm on the same bench in the same room in the same clothes except for one shoe cover. But entering a room "clean" to NASA standards - as I'm doing at ManTech International in Huntsville's Cummings Research Park - is both psychological and physical. Yes, I've been through the shoe scrubber and stepped on the tacky mat to get this far, but now I'm officially on the "clean" side. I need to pay attention.

Next come the layers

I cover the other shoe and add a shower-like cap of the same thin material. Ed Fahey, ManTech Contamination Control specialist, hands me a sealed plastic bag holding a white suit cleaned in a special laundry. I slip on both legs and pull the suit to my waist. Fahey passes me a pair of boots with leggings that reach above my calves and snap to the suit. Straps secure the boots to my feet.

I pull the suit over my shoulders and zip it up. Not all the way, because Fahey also hands me a hood with a long drape to cover my already covered head a second time. The drape stuffs inside the suit collar, along with the drape from a mask he hands me next. A thin pair of gloves pulls over the sleeves to complete the ensemble. I am now fully covered except for my eyes. It's time to step on another tacky mat at the clean room door.

What is the uniform for?

What is all this cleanliness for? I'm about to photograph - when my iPhone is scrubbed acceptably clean - a thin piece of very special plastic that will shield the James Webb Space Telescope from the sun's heat at the telescope's final destination 1 million miles from Earth in deep space. This is actual "flight hardware," as NASA calls it, the first of five state-of-the-technical-art shields made in Huntsville by ManTech and undergoing final testing in a clean room not far from the U.S. Space & Rocket Center.

I've been told how to walk in the clean room - slowly, methodically - and I follow Greg Laue, ManTech's sunshield program manager and director of aerospace products, who walks like an ice skater with both hands clasped behind his back.

The attention to detail just getting here is a tiny glimpse of the incredible complexity of sending something into space. The shield itself is thinner than a human hair but the size of a tennis court. It is made of Kapton, a high-performance plastic with a reflective aluminum coating. The shield is welded and assembled with specialized techniques invented and patented by ManTech in Huntsville.

In the next year and a half, Lead Analyst Branwen Schuettpelz, Quality Assurance Manager Greg Farmer, Lead Test Engineer Joshua Johnson and their team will put all five flight shields through these final strength and shape tests. Each test will be exhaustively documented.

What is the most fascinating?

Standing beside the shield, it's hard to decide what's most fascinating about what you're seeing. Is it the technical challenge of turning a computer design into something that can fly in space? Is it the fact this very object will be in deep space a few years from now? Or is it what seems to excite Laue most this day: thinking about the scientific leap America is daring with this telescope. No other country could do this, he says.

The Webb must launch perfectly in 2018, reach its orbit 1 million miles away perfectly, unfold perfectly, and start and work perfectly. It is too far for a repair mission if something goes wrong.

But when it is finally there, the Webb's mirrors, polished at a plant in Cullman, Ala. and tested at Huntsville's Marshall Space Flight Center, will show the world images from closer to the beginning of the universe than ever before. And the shields made in Huntsville, Ala. will be its only protection from the sun's disabling light and heat.

Updated Oct. 9 at 9:30 a.m. to make minor corrections