New Delhi: Scientists are said to have found traces of first stars which suggests that they winked to life roughly 250 million years after the Big Bang.
Smithsonianmag.com quotes Ethan Siegal at Forbes as reporting that the current generation of telescopes, like the Hubble Space Telescope, aren’t equipped to gaze into the deepest depths of space and time. GNZ-11 - is the oldest and furthest galaxy directly detected. It was formed just 400 million years after the Big Bang.
However, the report says that the scientists believe that the first stars began to flicker on sometime between 380,000 years after the Big Bang. It also says that according to many astronomers the first stars lit up around 200 million years after the Big Bang.
But a glimpse of these stars has not been successfully captured. It is hard to detect without specially equipped IR telescopes as after billions of years of travel their light shifts into the infrared end of the spectrum.
The website says that for a new study in the journal Nature, an international team of astronomers relied on indirect evidence. They searched instead for signatures of oxygen and helium. These elements that can only be created in the cores of stars.
The researchers focussed on galaxy MACS1149-JD1 - it lies billions of light years away - using two Earth-bound telescopes, namely the Atacama Large Millimetre/Submillimetre Array (Alma) and the European Southern Observatory’s Very Large Telescope (VLT). The researchers found that over billions of years, the expansion of the universe shifts that light, as per Smithsonianmag.com. When they analysed that shift, the researchers were able to figure out the age of the oxygen and hydrogen signatures. But they can’t directly see the galaxy.
Richard Ellis, a professor of astrophysics at University College London and co-author of the study, was quoted by the website as telling Jonathan Amos of BBC - that the oxygen has a redshift of 9.1 and that means the "Universe has expanded nine to 10 times since the light left this object. We’re looking back about 97 percent of the way to the Big Bang [13.8 billion years ago] when the Universe was only about 500 million years old... we find this galaxy formed its stars when the Universe was only 250 million years old, which is like 2 percent of the present age of the Universe."