How to Measure Distance in the Universe

The best red giant candidates are old stars that are on like the outskirts of galaxies which tend to be less dusty. These things are a little harder to find so there aren't as many examples but recently people have been working really hard on this using it to measure independently the expansion rate of the universe. You can actually see these in distance galaxies because usually when you look at a distant galaxy it just looks like a fuzz you can actually make out a little pinpoint in them. By measuring the gravitational wave frequency you can sort of predict the intensity of the gravitational wave as it was emitted and compare it to the intensity you measure here on earth.