"Nikola Tesla and the Electrical Signals of Planetary Origin," K. L. Corum and J. F. Corum, Ph.D., International Tesla Conference, "Tesla, III Millennium," Belgrade, Yugoslavia. 1996. 82 pp. Illustrated.

Abstract: This paper reports on an engineering study conducted to evaluate the possibility that Nikola Tesla's Colorado Springs receivers could receive the 10 GW kilometric radiation from Jupiter discovered during the Voyager I fly-by of that planet.  A little known result, drawn from the Appleton-Hartree Equation and experimentally confirmed by the U.S. Naval Research Laboratory many years ago, demonstrates that during solar minima there is an ionospheric-transparency window near 18 kHz, the very frequencies and conditions under which Tesla's Colorado Springs receivers operated. 

A careful replication and analysis of these receivers clearly indicates that Tesla employed a two-port regenerative feedback technology that achieved a remarkable sensitivity for that day (less than 100 microvolts).  While the receivers are not envelope detectors, they do give a triggered 400 Hz audio "Beep" in response to impulsive radiation.  Consequently, their response to the singlet, doublet and triplet pulses observed to be emanating from Jupiter would be, "Beep . . . Beep-Beep . . . Beep-Beep-Beep."  On several occasions we have heard such signals from replicated Tesla receivers (the signals are not inherent in the electronics) and we have even recorded them on audio tape for others to hear also.  (Skeptics may reconstruct their own apparatus and actually listen to the signals for themselves.)

Not only do we conclude that Tesla's receivers were more than adequate for the reception of the kilometric Jovian signals, but a computer search of Jupiter's storms predicted for the summer of 1899 reveal that, on several nights, these radiations ceased precisely as Mars dipped below the visual horizon at Colorado Springs.  Any correlation would surely imply to a casual observer that the signals might be of Martian origin.

We conclude that, far from being an absurd assertion, a staggering scientific discovery had been made.  Tesla's observations, performed during the summer of 1899, preceded Karl Jansky's by more than three decades.  (Jansky, like Tesla, was monitoring the radio signals from atmospheric storms.)  We believe that it can now be maintained that Tesla's were the first successful observations in radio astronomy and that they were, indeed, signals of planetary origin.