Washington, Feb 13 : The NASA/ESA Hubble Space Telescope has found a galaxy that was likely one of the youngest and brightest galaxies ever right after the cosmic "dark ages", just 700 million years after the beginning of our Universe.
The cosmic "dark ages" refers to a period in the early universe when the first stars and galaxies were just beginning to burst to life. This period lasted from about 400,000 to roughly a billion years after the Big Bang.
Now, using the Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS), astronomers have revealed images of an infant galaxy, dubbed A1689-zD1, undergoing a firestorm of star birth as it comes out of the dark ages, a time shortly after the Big Bang, but before the first stars completed the reheating of the cold, dark Universe.
Images from NASA's Spitzer Space Telescope's Infrared Array Camera provided strong additional evidence that it was a young star-forming galaxy in the dark ages.
"We certainly were surprised to find such a bright young galaxy 13 billion years in the past", said astronomer Garth Illingworth of the University of California, Santa Cruz, USA and a member of the research team. "This is the most detailed look to date at an object so far back in time," he added.
"The Hubble images yield insight into the galaxy's structure that we cannot get with any other telescope," added astronomer Rychard Bouwens of the University of California, Santa Cruz, one of the co-discoverers of this galaxy.
The new images should offer insights into the formative years of galaxy birth and evolution and yield information on the types of objects that may have contributed to ending the dark ages.
Current theory holds that the dark ages began about 400,000 years after the Big Bang, as matter in the expanding Universe cooled and formed clouds of cold hydrogen. These cold clouds pervaded the Universe like a thick fog.
At some point during this era, stars and galaxies started to form. Their collective light heated and cleared the fog of cold hydrogen, and ended the dark ages about a billion years after the Big Bang.
"This galaxy presumably is one of the many galaxies that helped end the dark ages", said astronomer Larry Bradley of Johns Hopkins University in Baltimore, USA.
"Astronomers are fairly certain that high-energy objects such as quasars did not provide enough energy to end the dark ages of the Universe. But many young star-forming galaxies may have produced enough energy to end it," he explained.