Yet, another part ID question: Large blue dish Does anyone have an idea what the circled piece could be? Picture from this Flickr gallery.



I'm thinking it's circular so I've been scouring BrickLink for dishes and disks but have not been successful so far.  Any help would be greatly appreciated!
Set #4417- Aero Pod. 




Top. Part #4767 - Blue
Container, X-Pod Top Cap 9 x 9 x 1 1/3.
Middle.  Part #47674 -
Trans-Yellow Container, X-Pod Barrel Section 10 x 10 x 3 1/3.
Bottom.  Part #47676 - Blue
Container, X-Pod Bottom Cap 9 x 9 x 1.