No, it hasn’t happened yet…unless you count the “wow” event :rolleyes: .
Suppose we encounter a radio transmission from an extra-terrestrial planet or ship. How do we compensate for the doppler shift of an object moving toward/away in respect to Earth at an uneven rate?
I mean, a planet orbits a star, and in regards to a distant stationary object, is seen to approach and then recede. This means its frequency increases and decreases.
How does SETI compensate for that?