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Al Jazeera has a terrific collection of Space Shuttle photos. In photo #11 we can see something bright in each Space Shuttle Main Engine (SSME) as Endeavour lands. What might that be? A reflection off the back of the combustion chamber? Something related to the auxiliary power units (APUs) venting through the SSMEs?

Here's a smaller cropped version; see the "photo #11" link for the original.

Endeavour landing

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left over propellant in the plumbing? – Nic Jan 20 '12 at 14:05
up vote 9 down vote accepted

You can see in this shot from a Gizmodo article the injector at the centre of the engine is quite reflective.

I assume that it is this catching the spotlights illuminating the shuttle that we can see in that shot.

Injector Nozzle on SSME from Gizmodo.

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Yep, seems logical. – ghoppe Jan 24 '12 at 21:39
Nice find! Thanks! – dotancohen Jan 25 '12 at 18:53
Ha... Ha... Ha... So simple! – Evil Angel Dec 10 '12 at 5:13

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