Premise 1: From the frame of reference of the earth, observing a thing falling into a black hole (crossing the Schwarzschild radius) is impossible -> the thing is observed falling toward but never reaching the radius, i.e. the process takes an infinite amount of time. Premise 2: Observation includes any manner of measurement and/or signal detection etc. Premise 3: Another black hole qualifies as "a thing" which can fall toward the black hole Conclusion: Actual black hole merger can never be observed, only a process leading toward it but taking an infinite amount of time. Question1: If the conclusion is correct, observation of black hole merger is impossible, then WHAT was observed by LIGO, and why is not still occurring (granted the signals may be weakening... but I assume that in our frame of reference the black holes are still merging.. and will continue to do so "forever") i.e. Did LIGO detect an actual merger or only an approach towards merger? Question 2: If the conclusion is incorrect which of the premises is false or how do the set of premises not logically necessitate the Conclusion?