This color composite image of the Hubble Ultra Deep Field was created using data taken by its WFC3 and ACS instruments. The green circles mark the locations of candidate galaxies at redshifts about z =8-10, when the Universe was only 650-480 million years old. About 20-30 percent of these candidates are very close to foreground galaxies, which is consistent with the prediction that a significant fraction of galaxies that we could see at these very high redshifts are gravitationally lensed by individual foreground galaxies.
Photo credit: NASA, ESA, Z. Levay and A. Feild (STScI). Data Credit: S. Beckwith (STScI) and the HUDF team; G. Illingworth and R. Bouwens (University of California, Santa Cruz), and the HUDF09 Team.