When matter is flowing into a black hole, it generally forms a disk, and a jet of outflowing material can also be formed perpendicular to this inflowing disk of matter. By tracking the motions associated with this jet of outflowing material, astronomers can infer properties about the black hole. This article describes one such study, helping to advance this area of research.

http://www.raa-journal.org/raa/index.php/raa/article/view/2122