NASA`s Hubble Space telescope has uncovered a primordial population of compact and ultra blue galaxies never seen before.The galaxies were found at a distance beyond anything previously discovered.
As the Hubble telescope looks deeper into space it to looks further back in time. With Hubble Astronomers are able to see galaxies as they were 13 billion years ago, just 600-800million years post the Big Bang.
The existence of these newly found galaxies pushes back the time when galaxies began to form to before 500-600 million years after the Big Bang. This is good news for astronomers building the much more powerful James Webb Space Telescope (planned for launch in 2014), which will allow astronomers to study the detailed nature of primordial galaxies and discover many more even farther away. There should be a lot for Webb to hunt for.
The Images and data were captured using Hubble’s new instrument, the Wide Field Camera 3. Taken in August 2009 astronomers from more then five international teams have been analyzing the data and have produced papers relating to the findings. Early analytic results are to be presented on Jan 6, 2010 at the 215th AAS meeting in Washington DC.
Garth Illingworth of the University of California, Santa Cruz, leader of the survey team that was awarded the time to take the new WFC3 infrared data on the Hubble Ultra Deep Field (imaged in visible light by the Advanced Camera for Surveys in 2004) quoted, “With the rejuvenated Hubble and its new instruments, we are now entering uncharted territory that is ripe for new discoveries, The deepest-ever near-infrared view of the universe — the HUDF09 image — has now been combined with the deepest-ever optical image — the original HUDF (taken in 2004) — to push back the frontiers of the searches for the first galaxies and to explore their nature.”
Rychard Bouwens of the University of California, Santa Cruz, a member of Illingworth’s team and leader of a paper on the striking properties of these galaxies, says that, “the faintest galaxies are now showing signs of linkage to their origins from the first stars. They are so blue that they must be extremely deficient in heavy elements, thus representing a population that has nearly primordial characteristics.”
James Dunlop of the University of Edinburgh, agrees and says, “There must be a substantial component of galaxies beyond Hubble’s detection limit.”
These newly found objects are crucial to understanding the evolutionary link between the birth of the first stars, the formation of the first galaxies, and the sequence of evolutionary events that resulted in the assembly of our Milky Way and the other “mature” elliptical and majestic spiral galaxies in today’s universe.
The HUDF09 team also combined the new Hubble data with observations from NASA’s Spitzer Space Telescope to estimate the ages and masses of these primordial galaxies. “The masses are just 1 percent of those of the Milky Way,” explains team member Ivo Labbe of the Carnegie Institute of Washington, leader of two papers on the data from the combined NASA Great Observatories. He further noted that “to our surprise, the results show that these galaxies at 700 million years after the Big Bang must have started forming stars hundreds of millions of years earlier, pushing back the time of the earliest star formation in the universe.”