Gouge Found on Shuttle Endeavour's Underside

SonicSpike writes " NASA has discovered a chunk missing from the underside of the space shuttle Endeavour. It was discovered after the shuttle docked with the ISS earlier today. Technicians theorize it may have been caused by ice ripping free of a fuel take during takeoff. From the article:'The gouge — about 3 inches square — was spotted in zoom-in photography taken by the space station crew shortly before Endeavour delivered teacher-astronaut Barbara Morgan and her six crewmates to the orbiting outpost ... On Sunday, the astronauts will inspect the area, using Endeavour's 100-foot robot arm and extension beam. Lasers on the end of the beam will gauge the exact size and depth of the gouge, Shannon said, and then engineering analyses will determine whether the damage is severe enough to warrant repairs. Radar images show a white spray or streak coming off Endeavour 58 seconds after liftoff. Engineers theorize that if the debris was ice, it pierced the tile and then broke up, scraping the area downwind. Pictures from Friday's photo inspection show downwind scrapes."

Comments

Re:Can't be the First Time

[florescent_beige]

I wonder how many times this kind of thing happened...

Lots (yes it's a pdf so kill me). See page 9.

Sorta reminds me of the time the de Havilland Comet blew up in mid air and aviation engineers learned about fatigue and decided to go look at other airplanes for signs of fatigue cracks and found them everywhere. Talk about freaking out.

Then, after that, several smart people[1] figured out that cracks always had been everywhere and, you know, chill. The airplanes we fly around on have lots of cracks. The thing that saves our collective butts is that they are understood.

1 P Paris and F Erdogan (1963), A critical analysis of crack propagation laws, Journal of Basic Engineering, Transactions of the American Society of Mechanical Engineers, December 1963, pp.528-534.

The shuttle can land without pilots

[Mal Reynolds]

The Discovery was given remote landing capability in 2006. I would be shocked if the Endeavour didn't have this same capability.

http://science.slashdot.org/article.pl?sid=06/06/3 0/0458246&from=rss

If mission control thinks a manned landing too risky, they'll just hook up the remote system and send down the can without the spam. Another Shuttle will be sent up in 6 or 8 weeks and take the whole lot of them home.

This would probably be another large setback to the ISS and to the astronaut corps. The "rescue mission" would probably depart with just 2 or 3 astronauts. And if the Endeavour was lost on re-entry, it would probably doom the shuttle program.

Sucks to be an astronaut these days. Chances of dying, 1 in 59, and you're lucky to get a single ride every 10 years.

On the other hand, SpaceX may get be getting some rush orders for Falcon 9's and Dragons.

Perseid meteor shower

[flewp]

I have some somewhat offtopic questions I was hoping someone here might be able to shed some light on.

Does anyone know how/if NASA handles things like micrometeorites? Now, I know that for the most part they're just tiny specks of debris, and *very far* and *very few* between, but do they have any kind of contingency plan for fixing either parts of the shuttle or the ISS in a case of impact? I've seen and heard a lot of times that even a small speck at those speeds can punch a rather large hole in even thick aluminum/steel/etc plating. Can a spec of dust truly do that much damage, or are they exaggerating and really talking about something more along the size of a pebble or even a grain of sand? It wouldn't surprise me to learn that a tiny speck of debris could indeed punch a huge whole, but it also wouldn't surprise me that even the scientific/educational* shows I've seen this on could be exaggerating for effect. (* I use scientific/educational loosely, as even stuff on the Discovery Science channel is still entertainment, especially more so now than ever it seems)

Also, how would an event like the Perseid meteor shower change the odds? Again, I realize that even during a meteor shower, the actual meteors and objects are extremely sparse. What I'm wondering is, do they (statistically speaking) increase the likelihood of an impact, or are they still so sparse as to have very little consequence?

And finally, about what is the lower limit for NASA and other agencies when it comes to tracking space junk and meteors that orbit the Earth? I know they have some kind of tracking system, but I'm wondering what its limits and capabilities are. Are they making efforts to curb space junk, since I imagine there's more stuff in orbit now than ever? Are the number of launches increasing with time as well, or have they sort of leveled off or even dropped off now that we have a lot of communication, research, etc satellites in orbit?

Apologies for asking here instead of googling, but I figured it might make for good discussion. Or at the very least, expand my knowledge a bit.

Re:Perseid meteor shower

[imemyself]

I've read that a little piece of paint made a fairly noticeable "dent" in the Shuttle's windshield. Here's a website that mentions it: http://www.spacetoday.org/Satellites/SatBytes/Spac eJunk.html

Several other sites showed up on Google when I searched for shuttle, fleck of paint, windshield

Considering how small the mass of the paint must have been, I could easily see how a small pebble sized object could cause major damage, but I'm not a rocket scientist. I think there has also been some general concern about all of the debris from China's ASAT test earlier this year. I think they are tracking most of the thousands of pieces of debris, so they would hopefully have an idea if something was coming, but I'm sure that they can't track the smallest pieces of debris. There are some animations on the web that show how the debris spread out from that test - its really amazing.

When you're traveling at 7 km per second, hitting anything that is not traveling along with you on a similar orbit (they would have similar velocities and wouldn't be moving as fast relative to you) has got to be seriously bad news.