Special lensing effect
The farthest galaxy (MS 1512-cB58) is the brightest known celestial body at such a large distance and such an early time. This is due to the lucky circumstance: a massive cluster of galaxies (MS1512+36) is located about halfway along the line-of-sight, at a distance of about seven billion light years and acts as a gravitational "magnifying glass'. Thanks to this lensing effect, the image of the galaxy appears 50 times brighter. Nevertheless, the apparent brightness is still as faint as magnitude 20.6, i.e., nearly 1 million times fainter than what can be perceived with the unaided eye. Moreover, the galaxy is located 36 degrees north of the celestial equator and can, therefore, only be observed for about 90 minutes each night from Paranal observatory in the University of Hawaii (at geographical latitude 25 degrees south). It was a great challenge for scientists to secure the present observational data using the ultraviolet-visual echelle spectrograph (UVES). The extremely detailed UVES-spectrum of the galaxy displays numerous absorption lines of intergalactic gas clouds along the line-of-sight. Some of the clouds are close to the galaxy and the astronomers are investigating the distribution of matter in its immediate surroundings. The new observations will provide an invaluable contribution to ongoing studies of the birth and evolution of the structures in the early universe.