Switching your cellphone off in this American town is mandatory.
Green Bank is located in the state of West Virginia, a smack dab in the middle of the 33,670 square-kilometre stretch of land otherwise known as the National Radio Quiet Zone (NRQZ).
The area is home to the largest steerable telescope in the world — the Green Bank Telescope is 0.80 hectares wide and reaches 147 metres in to the sky.
Scientists conduct searches of the galaxies for signals weaker than billionths of a watt at the facility. However stray beacons can cause interference in the telescope's range and readings.
What does this mean for the area's population? No Wi-Fi, Bluetooth or cellphones.
The town resembles the Square Kilometre Array (SKA) site in the Karoo desert of South Africa — which comprises 131,500 hectares of land, with 176 telescopes. The SKA site also needs to be free from radio-frequency interference.
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