This might be sound from beyond a blackhole. It could be the anti-phonon version of an inter-galactic event that supplied humanity with our first gravitational wave recording shortly after the detector was constructed and operational.
I am not sure what it is yet to be honest. What do you think it is?
From those who published... 
Am I to understand that gravitational waves should behave opposite a wave on earth where intereferent matter causes waves to begin with a sharper peak rather than end with a sharp peak. Few sounds on earth beside the odd bird song sound that way and produce that specific late-peaked wave form. The wave-form is reversed to the sounds I have recorded.
If gravity is a concept that requires two masses sharing a connection by proximity ..what is this concept of gravity coming in waves from 10 billion light years away? ..I call foul till resolved.
If it is defined as a wave/frequency RESULTING from interactions involving gravity ten billion light years away, I can accept that.
That however does not qualify the title of gravitational wave, IMO. It would most accurately be described as a wave of something else resulting from the far away collision.
If there are not two masses expressing angular and/either linear force in the system, a rotating sphere on it's own cannot express nor be subject to gravity. It expresses the complimentary force, centrifugal (outward from center of mass).
In the case where there are not two masses, a single pole can be simulated by high-voltage flux emission. The configuration will not yield gravity, it will allow one to apply the complimentary forces that counter it's effect upon an object.
Oh my... they share a center of mass through space? ..they even share a dipole linear/mass polarity of convergent bodies in space as one object/system.