What's the reflection of in Gordon's glasses?

[DocRock]

This just caught my eye, but doesn't it look like there's a reflection of something in Gordon's glasses?

 

[Gordon'sFreeman]

its called light

 

[Bleeder]

That's a reflection of me crying. How the hell can you even bring this up at a time like this?

 

[mbrithoms]

its buildings, probably c17

 

[mrchimp]

looks abit like the citadel and some other buildings