What is the question? Is it:

(a) Where, if anywhere, do you have to be in order to see the mote; or

(b) If you see the mote, where does it appear to be?

Hi Chris,

Good questions.  We know we can see motes in light, especially sunlight and you are standing on a darker side.  I think, from the question the mote is suspended in the centre of the sphere

It feels as if (I'm trying to visualise it) the photons travelling from the mote to either eye will hit the surface of the sphere perpendicularly, so they won't refract, so it would appear to be in the centre?

But I'm quite prepared to be shown to be wrong 

As it happens I have a globe shaped storm glass* on my shelf, so I did a quick experiment swirling it around, it does appear that the crystals in the centre seem to be in the centre (just by the way they don't move when I spin it), and neither magnified nor minified(is there such a word?). Not very scientific though.  

* en.wikipedia.org/.../Storm_glass

I am inclined to agree, it is only an offset defect that would appear in the 'wrong place' but if there was any doubt, then you could immerse the whole thing in an oil of similar refractive index to the glass (a so called 'index matching' fluid or gel for the less runny ones ), and then there would be no beam bending at the surface.

Mike.

I am inclined to agree, it is only an offset defect that would appear in the 'wrong place' but if there was any doubt, then you could immerse the whole thing in an oil of similar refractive index to the glass (a so called 'index matching' fluid or gel for the less runny ones ), and then there would be no beam bending at the surface.

Mike.