I saw a news article about night shining clouds on the edge iof space. Pretty interesting until I came across the screw up (I think) stating that 400 tons of water from the shuttle exhaust caused one of these clouds to form. Care to give a explanation?
http://www.space.com/scienceastronomy/080901-mm-night-shining.html
Interesting question, Huck. Well, a little known fact is that the Shuttle's exhaust is about 90% water. Just a quick lookup shows the shuttle takes off with about 830 tons of propellant. However, the fuel burned when the shuttle is close to the ground cannot contribute to noctilucent clouds since it isn't high enough in the atmosphere. The shuttle has to be about halfway to orbit for the exhaust to be high enough to form noctilucent clouds, which jives nicely with the 400 tons of water sited (exhaust from the solid rockets is irrelevant since they drop off before the shuttle is high enough).
ReplyDeleteThe evidence comes from the Middle Atmosphere High Resolution Spectrograph Investigation which flew on the Shuttle in 1997. They were able to track the water vapor plume as it migrated northward and formed noctilucent clouds. You can read a NASA article about it here.
Fortunately, I am a little far south to see them...I like the heat!
That's what I was thinking, but the example used was the shuttle that crashed which leads one to think it happened during the crash.
ReplyDeleteConsidering every shuttle puts out this amount (and othe rockets too) there should be more of these clouds, no?
And just to add to the confusion, Huck, the paper outlining this work was published in 2003, the same year as the Columbia accident.
ReplyDeleteInteresting question...it would depend on the launch. Most rockets give off much less water vapor than the shuttle. Rockets launched from the ESA site near the equator might not be able to get their water vapor to the pole. So it probably only happens for relatively large rockets launched far enough north (or south).