I find it hard to believe this was detectable with a 2.5 mile detector. If you had a detector that was from here to the sun it would change length by 1 part in 5 x 10^22
Distance to sun 150,000,000 km
150,000,000/5 x 10^22 = 3 x 10^-15
That is 3 nm or about 1/200th of the wavelength of red light. And there detector was 30 million times smaller!
It's either very incredible or very suspicious.
Just saying,
Mike.
Edit, Seems the sensitivity claimed is 1 in 5 x 10^22, gravity waves distort by 1 in 10^20. So, I was out by a factor of 500!! Their 4km detector would distort 400 X 10^-15 m = 400 femto meters!!!