Illustration of a supermassive black hole seed (main image). The lefthand inset shows a seed candidate imaged in X-ray light by NASA’s Chandra X-ray Observatory; the righthand inset shows the same seed in optical light (center) as seen by NASA’s Hubble Space Telescope. Credit: X-ray: NASA/CXC/Scuola Normale Superiore/Pacucci, F. et al, Optical: NASA/STScI; Illustration: NASA/CXC/M.Weiss