[jacquesm]

On days with clouds it won't matter at all. And on days without clouds it will be a tiny cloud at that distance, one that moves relative to the sun/earth line of sight because it would have to be geostationary, so it will rotate with the earth.

Which means the time of 'transit' would be the time the image of the sun takes to move a single solar diameter across the sky, and only for those people who are in the line-of-sight, so it would be a different group of people almost every time this happens, at most twice every year.

No such 'guy' would exist.