> it just happens to be a frequency near one we expect to be used as a signal.
What's the reasoning for this? I've seen noted that the Wow signal of 1420 MHz is near the hydrogen line frequency, and is commonly detected astrophysically.
So is the reasoning just that, if you want to send a signal, then you might choose this frequency because other civilizations will probably have detectors tuned to it?
But then the flip-side of that is that if you detect this frequency, then it's almost certainly natural origin, from the excitation of hydrogen.
What's the reasoning for this? I've seen noted that the Wow signal of 1420 MHz is near the hydrogen line frequency, and is commonly detected astrophysically.
So is the reasoning just that, if you want to send a signal, then you might choose this frequency because other civilizations will probably have detectors tuned to it?
But then the flip-side of that is that if you detect this frequency, then it's almost certainly natural origin, from the excitation of hydrogen.