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Radiant heating of air trapped in hollow glass spheres?

Radiant heating of air trapped in hollow glass spheres?

Radiant heating of air trapped in hollow glass spheres?

Assume two hollow sealed clear glass spheres, let's say both about 2 foot diameter each.
Glass is typical thickness and transparency of single pane window, inside just trapped air.

Temperature of spheres and air inside and outside is the same, 70 degrees F, for both spheres
when first positioned outside in the morning before sun rise.

Spheres then exposed to rising sun for hours, outside ambient air temperature climbs to over
100 degrees F, but let's also assume the glass was super insulated somehow and there was no
convection/conduction transference from the hotter outside air to and through the glass to
then raise the temp of the air inside the sphere. They both only have radiant heat intruding.

The two spheres differ as follows...

#1 sphere is as described above.

#2 sphere is the same, except that it has a silver reflective coating on half of the inside of
the glass and it stays positioned, relative to the sun, where that reflective coating is always
on the bottom and sunshine is always streaming in on the clear top hemisphere.

Question; Would air temp inside either likely rise significantly higher than starting temp of 70F,
when only being exposed externally to short wave IR of direct sunlight?

And, would there be much of a difference in internal air temp between the two different sphere's?

Appreciate any thoughts, thanks.

- Shane

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