http://cosmiclog.msnbc.msn.com:80/ar.../11/19898.aspx


Discovery's Ring of Fire // Alan Boyle's 'cosmic Log'
Posted: Monday, December 11, 2006 4:13 PM
When the space shuttle Discovery soared through the night sky on Saturday
night, a camera mounted on the craft's external fuel tank beamed back a
light show that had never been seen before - at least from this particular
perspective. Arcs of multicolored lights shimmered around the orbiter
itself, looking for all the world like an aurora. You can watch the display
by clicking on this video link.

But what's behind the spectacle? NBC News space analyst James Oberg went to
some effort to explain the physics behind the show:

snip