The United States has a limited capability to track targeted cell phone communications anywhere in the world. The Orion-class Signals Intelligence satellites a

The United States has a limited capability to track targeted cell phone communications anywhere in the world. The Orion-class Signals Intelligence satellites are claimed to be the largest in space, with a primary dish diameter of about 100 meters. https://en.m.wikipedia.org/wiki/Orion_(satellite) https://en.m.wikipedia.org/wiki/Orion_(satellite) The Green Bank radio telescope is a dish on that scale, and it looks just wrong, too large to be real. The usual portrait shot doesn't do it justice, but try to put a mental image together from the photos up on the Commons: https://commons.m.wikimedia.org/wiki/Category:Green_Bank_Telescope https://commons.m.wikimedia.org/wiki/Category:Green_Bank_Tel... I spent a week out there during its construction. There were contractor shacks - cargo container size - up there on the platform at the base of the elevation gear (photo labeled "Altitude" on the page linked above). So right now, in space, you have soccer-stadium-sized satellites. They are far less massive than the GBT, not solid surface. But very large.