Planetary defense shield

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Earth Defense Directorate operators before a large towering wall-sized monitor as Ranger 3 makes its unauthorized approach (BR25Film, "Awakening").

A planetary defense shield overseen by the Earth Defense Directorate ensconces the Earth in an impenetrable, protective energy barrier.

This defense shield is able to protect Earth from extra-terrestrial threats, including those posed by the Draconian Empire. The field can be adjusted, but is typically projected more than 100 miles above Earth's surface, but can be retracted to 100 miles in order for approaching ships to be investigated (BR25Film, "Awakening").

A narrow channel within the shield is created for military use, allowing Thunderfighters and other crafts ingress and egress from Earth. Kane secretly plants a microtransmitter aboard William "Buck" Rogers's Ranger 3 on the belief that the Defense Directorate would escort him through this channel, which inevitably happens (BR25Film, "Awakening").