The gravitational wave based distance measurements are really awesome because they are the only way to verify red shift distances. You can calculate how strong

The gravitational wave based distance measurements are really awesome because they are the only way to verify red shift distances. You can calculate how strong the wave should be based on the difference in mass between the two objects before collision and the combined object after and then calculate how strong the wave should be when it reaches earth. Right now the precision of the distances are only 10% but in the future when something like the Cosmic Explorer with 40km arms is built they will get a lot more precise.