The island in the picture is 9' and the fixture spacing is about 42", but it really depends on the fixture you're using. These are pretty big fixtures, so they can be spaced pretty far apart. I'd hate to give you a spacing dimension and have it not work correctly for your project.

Thanks so much for your advice. I appreciate it. We're using this same pendant as shown here (yoke by visual comfort). Our island is 9 x 4.8. You have used it beautifully here.