Why does the Green Bank Telescope (GBT) require large radio quiet zones for protection?

Answer

Its extreme sensitivity allows it to detect radio noise from common electronic devices.

The GBT's sensitivity is so high that electronic noise, such as from a cell phone even on Mars, could interfere with its observations of faint cosmic signals, necessitating protection via radio quiet zones against electromagnetic pollution.

Why does the Green Bank Telescope (GBT) require large radio quiet zones for protection?
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