LIGO: How to Know Wave Direction?

[nmsurobert]

Im sure you guys see a lot of this. I only come here when google has let me down for several hours.

How does LIGO know where the waves are coming from?
My guess is that they can get an idea of the direction of the wave based on how the arms are stretched of compressed.

Thanks.

 

[mfb]

LIGO has two detectors, Virgo is a third detector. Based on the arrival times (e. g. "Virgo first, 20 ms afterwards at one LIGO site, 3 ms later at the other LIGO site") it is possible to figure out from which direction the gravitational wave came. The relative amplitudes help a bit as well as the different detectors have different orientations.

 

[nmsurobert]

LIGO has two detectors, Virgo is a third detector. Based on the arrival times (e. g. "Virgo first, 20 ms afterwards at one LIGO site, 3 ms later at the other LIGO site") it is possible to figure out from which direction the gravitational wave came. The relative amplitudes help a bit as well as the different detectors have different orientations.

that makes total sense. thank you!