HIDE AND SEEK Galaxies around as early as 1 billion years after the Big Bang, seen in this composite image from the Chandra and Hubble space telescopes, show no evidence of X-rays (blue) from growing black holes.
E. Treister et al/University of Hawaii/CXC/NASA (X-ray); G. Illingworth et al/University of California, Santa Cruz/STScI/NASA (infrared); Optical: S. Beckwith et al/STScI/NASA (optical).