Astronomers say that the earliest stars in outer space are younger than what was previously determined. 140 million years younger to be precise. So, how have the stars gotten younger? Astronomers utilized and analyzed data gathered by the Planck telescope at the European Space Agency and came to new conclusions.
Over the course of a few years (roughly between 2009 and 2013) the Planck telescope measured the cosmic microwave background (CMB). CMB is the oldest source of light in the universe. This light came into existence as the newly formed hot and dense universe cooled and expanded. CMB is thought to be between 13.7 and 13.8 billion years old. At the end of Planck’s study astronomers had a high-resolution map of CMB and the polarization of temperatures across the firmament.
Before this research was complete, early estimates agreed that the peak of early star development was approximately 420 million years after the Big Bang. These previous approximations were made with the use of NASA’s Wilkinson Microwave Anisotropy Probe (WMAP). The problem was that the Hubble Telescope could not spot a sufficient number of galaxies old enough to fit with this timeline. Planck solved this problem.
After spending a few years immersed in analysis of Planck’s new CMB map, scientists at the European Space Agency have come to conclude that stars did not appear until 140 million years later than the previous estimate. So, according to these calculation, the stars have gotten younger.
This mean that the cosmic dark ages (the time before the first light) lasted longer than what was previously thought to be true. Professor of Astrophysics, George Efstathiou works with the Planck Science Collaboration team and claims that this new data is significant. He states, “Proportionately it’s actually a very big change in our understanding of how certain key events progressed at the earliest epochs.”
After the Big Bang was the period containing the era dark age. It stayed dark for hundreds of millions of year until gravity began to draw matter together. The first stars and galaxies began to emit light and helped to clear away a fog of hydrogen atoms that shrouded space. The photons that are created by stars ionized the hydrogen atoms and quasars and galaxies began to come into existence. This period is known as the re-ionization era.
The new data take from the map made by Planck could help provide more information and details about the re-ionization era in the future. One study scientific study that might already be underway is the careful investigation of the map for subtle distortions. This might revel to astronomers any other interactions (caused by environmental changes) the CMB had on its way to present time.
The exact timing of the appearance of the very first star is still unknown, and will potentially always remain unknown. Nonetheless, the map provided by Planck displays that large clusters of early stars did in fact appear roughly 560 million years after the Big Bang.
In terms human understanding, although not in the reality, today the stars have gotten younger. Thanks to the Planck telescope and the devotion of astronomers, a little more light has been shed on when things happened in the early universe.
By Emilee Prado