Hubble Discovers the Oldest Galaxies Ever Observed
Por Dialogo janeiro 07, 2010The Hubble Telescope has broken a new record by discovering the oldest galaxies yet observed, dating from 13 billion years ago, which is to say 600 to 800 million years after the Big Bang, NASA announced Tuesday. These newly discovered cosmic objects are essential for understanding the evolution that took place from the birth of the first stars to the formation of the first galaxies, which would later give way to the creation of the Milky Way and other elliptical galaxies that populate the present universe, the astrophysicists involved in the discovery indicated. The team of astronomers combined the information provided by the new instruments on the Hubble (the first space telescope) and observations made using the Spitzer Space Telescope in order to calculate the ages and masses of these first galaxies. “The masses are just one percent of those of the Milky Way,” explained Ivo Labbé of Carnegie Observatories, one of the members of the research team. “To our surprise, the results show that these galaxies at 700 million years after the Big Bang (the theoretical beginning of the universe) must have started forming stars hundreds of millions of years earlier, pushing back the time of the earliest star formation in the Universe,” he added. “With the rejuvenated Hubble (repaired and updated in May 2009) and its new instruments, we are now entering unchartered territory that is ripe for new discoveries,” emphasized Garth Illingworth of the University of California at Santa Cruz, one of the leaders of the project.