Is the glass half empty, or is it half full?

The Space Patrol would like to take this opportunity to remind you that - as easy as it is to take the apparently 'empty' half of this glass for granted - in some places that half can be the most important one of all.

Empty, schmempty! One half of THIS glass is filled with atmosphere. And, atmosphere? Well, when you need it... you really need it. Take it from us.

Just one of four carefully crafted answers to that eternal question: Is the glass half empty, or is it half full?