NASA's Hubble Space Telescope has reached back 13.2 billion years -- farther than ever before in time and space -- to reveal a "primordial population" of galaxies never seen before."The deeper Hubble looks into space, the farther back in time it looks, because light takes billions of years to cross the observable universe," the Space Telescope Science Institute said in a statement released Tuesday.
"This makes Hubble a powerful 'time machine' that allows astronomers to see galaxies as they were 13 billion years ago -- just 600 million to 800 million years after the Big Bang," the institute said in a statement released Tuesday.
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, the institute said.
"These galaxies could have roots stretching into an earlier population of stars. There must be a substantial component of galaxies beyond Hubble's detection limit," according to James Dunlop of the University of Edinburgh in Scotland, who was quoted in the release.
From the current cache of images, astronomers can see for the first time that "galaxies grew from small, bright clusters of stars to the big spiral cities of stars today," Villard said. The small galaxies show up as ultra-blue in color.
According to the institute, "the deep observations also demonstrate the progressive buildup of galaxies and provide further support for the hierarchical model of galaxy assembly, where small objects ... merge to form bigger objects over a smooth and steady but dramatic process of collision and agglomeration. It's like streams merging into tributaries and then into a bay."
The camera was pointed at a section of sky known as the Hubble Ultra Deep Field, which was initially surveyed in visible light in 2004, and showed a dark sky filled with more than 10,000 galaxies. –CNN Tech
No comments:
Post a Comment