One of the contractors has been helping me organize 30 years’ worth of flight hardware. I’ve enjoyed it because he worked in a different area for 20+ years, so I can tell all my stories because he hasn’t heard them before (dagnabbit). So the other morning, when I said, “Oh, here is my favorite sample!”, he laughed and asked, “How can you have a favorite sample?” There are at least a couple thousand samples, what makes this one so special?
Well, it flew on LDEF (see yesterday’s post), so it was one of the first flight samples I ever analyzed. It was a sample of the coating used on the Hubble Space Telescope handrails (Chemglaze Z-853, if you must know). Hubble was sitting in another clean room at the Kennedy Space Center, waiting for its April 1990 launch. And this little one-inch diameter sample shows just what the space environment can do.
This is a “half-moon” sample, where only the left side of the sample was exposed to space. Atomic oxygen has eroded away the polyurethane binder, leaving a diffuse surface of fine yellow pigment dust. On the right side, you can see how glossy the paint is supposed to be. This was located 38 degrees from the ram direction (velocity vector), so there’s little bits at the corners of the half-moon where there was UV radiation but it was shadowed from atomic oxygen, so there’s UV darkening of the remaining binder. Finally, the little black circle on the upper left is a meteoroid/space debris impact. AO, UV, MMOD, all on one sample.
Yes, I know I’m a nerd, but it’s still neat.