Thursday's grand announcement pointed out that the Livingston station (Louisiana) "heard" the gravitational wave "chirp" 7 milliseconds before the Hanford station (Washington) on Sept. 14, 2015. As gravitational waves travel at the speed of light, this timing difference confirmed that the two detections were indeed the same event. Scientists were immediately able to deduce the direction the gravitational waves were traveling.
NEWS: Gravitational Waves Detected for First Time
Now, the LIGO collaboration has released a map of the Southern Hemisphere skies, giving us a glimpse at the promising future of gravitational wave astronomy. In the map, contours have been added that represent the different probabilities for where the signal originated. The outermost purple line represents a 90 percent certainty that the signal's source (the colliding black holes) is contained within that area. The innermost white contour line highlights a possible source region to a 10 percent certainty.
The band of stars through the middle of the image is the edge-on disk of the Milky Way and the Large Magellanic Cloud and Small Magellanic Cloud (two small nearby galaxies) can also be seen in the bottom portion of the image. It is worth noting that, although there is some uncertainty in the black hole's distance, its location is far beyond our own galaxy and Local Group of galaxies.