Yes, it's a bit obscure.
They are two pieces of clear lucite that showcase space flown objects. These were made in limited amounts to support an astronaut scholarship fund.
One holds a small piece of ablative material from the heat shield of the Apollo-soyuz command module. This is the bottom section that burns away on reentry.
The other holds a piece of Skylab, which was one of the missions that Pogue flew. After Skylab was deactivated, Skylab eventually fell from orbit but large chunks survived reentry. One of the largest pieces that was recovered was an oxygen tank that landed in Western Australia. This piece of lucite holds a piece of that tank.