Episode 108: NASA’s Europa Clipper Mission

The Clarke Exobelt is the name that Dr Hector Socas-Navarro has
given to perhaps the largest structure humans have built. A
collection of satellites in earth orbit (geosynchronous) 36,000 km
radius. All circling the earth at the same speed in the same
direction. The density of this orbit has been increasing since the
1960s but is not yet sufficiently dense for detection from
interstellar distances. But in 200 years it may be. In the
meantime, this concept works the other way around too. SETI
researchers can search for these megastructures or Tecno Signatures
to look for extraterrestrial intelligence