Not directly ICBM related, but the Arecibo telescope detected an ionospheric anomaly in the 1979 Vela incident [0], believed to be an undeclared nuclear weapons

Not directly ICBM related, but the Arecibo telescope detected an ionospheric anomaly in the 1979 Vela incident [0], believed to be an undeclared nuclear weapons test. [0] https://en.wikipedia.org/wiki/Vela_incident https://en.wikipedia.org/wiki/Vela_incident