The Mystery Glow of Space Shuttles

As the NO leaves the shell of the spacecraft, it emits photons at a wavelength of 680 nm (orange)  

Support for this explanation came inadvertently in 1991, when astronauts aboard Discovery released various gases, including carbon dioxide, neon, xenon, and nitric oxide, from the cargo bay in the course of an unrelated experiment. Expelled one at a time, these gases scattered onto the surface of the shuttle s tail. The nitric oxide caused the normal shuttle glow to intensify nrarkedly, but the other gases had no effect on it. 

What is the source of the nitric oxide on the outside of the spacecraft Scientists believe that some of it may come from the exhaust gases emitted by the shuttle s rockets and that some of it is present in the surrounding atmosphere. The shuttle glow does not harm the vehicle, birt it does interfere with spectroscopic measurements on distant objects made from the spacecraft. 

1 What maximum wavelength (in nm) of light is necessary to break the bond in a nitrogen molecule (Ni) (The bond energy of N2 is 941.4 kJ/mol.) 

2 What process gives rise to the aurora borealis and the aurora australis  

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