Reading astronomy news always humbles me–makes me realize time and again my place in an enormous universe, the size of which is just unthinkable by my little human mind. This week I came across an article detailing the findings of Planck, the European telescope. It re-estimated the time, and the scientists seem to agree on this new number, the time of formation of the earliest stars in our universe. I was sort of lost in the science and the dazed by the timelines. 560 million years after Big Bang, which happened about 13.8 billion years ago? Can you even think about the ancientness of it all? I have to be honest–it sort of stuns me.
Anyway, thought of sharing some tidbits of Planck’s findings today. Here goes–
Observations made by the European telescope Planck has “effectively solved the conflict” regarding the dates of the earliest star formations. Previously, the American satellite WMAP, which operated in the 2000s, made an estimate for the peak of re-ionisation at 420 million years after the Big Bang. That re-ionisation would have been possible due to the first star formations.
There was a problem with that number though–the observations the Hubble Space Telescope observations of the early Universe contradicted that assumption. Hubble could not find enough stars and galaxies that could lead to that scale of environmental change at the 420 million years mark.
Planck’s new timing, which is set at 560 million years after the Big Bang, “effectively solves the conflict,” said Prof Richard McMahon from Cambridge University, UK. “We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the ‘now side’. It’s like a bridge being built over a river. The two sides do now join where previously we had a gap,” he told BBC News.
More from Physicsworld.com
The first stars and large-scale structure in our universe formed much later than previously thought, according to the latest maps and data from the European Space Agency’s Planck telescope, which has been scrutinizing the polarized fossil light from the early universe. Planck’s new timeline pinpoints when star formation began in the nascent universe. This signalled the end of the cosmic “dark ages” and knowing when it occurred will help improve our understanding of the earliest epochs of the universe.
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Marco Bersanelli of Università degli Studi di Milano, Italy. “Planck’s observations of the CMB polarization now tell us that these ‘dark ages’ ended some 550 million years after the Big Bang – more than 100 million years later than previously thought,” he adds, explaining that, while 100 million years may seem negligible compared to the universe’s age of almost 14 billion years, the timescale has a large impact when it comes to the formation of the first stars.
Link to the full article on physicsworld.com
A few portraits of our galaxy, as captured by Planck.