Astronomers said they have used the NASA's Hubble Space Telescope to spot a galaxy whose light traveled 13.2 billion years to reach Hubble, about 150 million years longer than the previous record holder.
According to NASA the tiny, dim object is a compact galaxy of blue stars that existed 480 million years after the big bang. More than 100 such mini-galaxies would be needed to make up our Milky Way. The new research offers surprising evidence that the rate of star birth in the early universe grew dramatically, increasing by about a factor of 10 from 480 million years to 650 million years after the big bang, NASA stated.
The galaxy appears as a faint dot of starlight in the Hubble exposures. It is too young and too small to have the familiar spiral shape that is characteristic of galaxies in the local universe. While individual stars can't be resolved by Hubble, the evidence suggests this is a compact galaxy of hot stars formed more than 100-to-200 million years earlier from gas trapped in a pocket of dark matter, NASA stated.
NASA said the discovery was made with the telescope's Wide Field Camera 3 right after it was installed in May 2009, during the last NASA space shuttle servicing mission to Hubble. After more than a year of detailed observations and analysis, the object was positively identified in the camera's Hubble Ultra Deep Field-Infrared data taken in the late summers of 2009 and 2010, NASA stated. The proto-galaxy is only visible at the farthest infrared wavelengths observable by Hubble, NASA noted.
Previous searches had found 47 galaxies at somewhat later times, when the universe was about 650 million years old. The rate of star birth therefore increased by about ten times in the interval from 480 million years to 650 million years. "This is an astonishing increase in such a short period, happening in just 1% of the age of the universe," says Ivo Labbe of the Carnegie Observatories, one of the authors of a paper on the new galaxy discovery. "We are thrilled to have discovered this galaxy, but we're equally surprised to have found only one. This tells us that the universe was changing very rapidly in early times."
Last year a European team of astronomers using results from the Hubble Space Telescope and the European Southern Observatory's Very Large Telescope (VLT) team spotted the faint glow of a galaxy 13.1 billion light years from our own. The galaxy, named UDFy-38135539 includes about a billion stars.
According to the Hubble Web site: "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. 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."
Follow Michael Cooney on Twitter: nwwlayer8
Layer 8 Extra
Check out these other hot stories: