You mean in Charlie's visor? That's the reflection of John Young, who was taking the picture.
Between John's reflection and the reflection of Charlie's shadow there's a bright patch of surface. It's bright because the camera sees it (via the reflection) at almost zero phase angle. This is called the opposition effect and it explains why the full moon is much more than twice as bright as a half moon. And a full moon is at its very brightest immediately before and after a lunar eclipse.
Simple rule for visor reflections: the image of the camera taking the picture always appears in the visor at the point on the visor closest to the camera.