  What is the chance we start a conversation with another civilization like our
own? Our technological society produced signals that could be received by other
extraterrestrial civilizations, within a sphere around us with a radius of
$\sim 10^2$ light years. Given that, the Copernican principle provides a lower
limit on the response time that we should expect from transmitters on
Earth-like planets around Sun-like stars. If our civilization lives longer, the
expected number of responses could increase. We explore the chance of detecting
a response in the future, and show that a response should only be expected to
arrive after a few millennia.
