Related Clues:

• Chicken Little's concern
• Astronomer's focus
• It's up there
• Fifth element
• Pilot's domain
• Firmament
• Some people reach for it
• Hit high in the air
• Jet setting
• It's above the horizon
• Where to look for pie?
• It goes around the world
• Kite setting
• Contrail milieu
• "Reach for the ___!" (oater phrase)