A new scientific data released by the European Space Agency (ESA) has once again sparked the debate over the age of the oldest known stars in the Universe.
The data, collected by the ESA’s Planck satellite, suggested that the first estimates of the age of these oldest stars could be wrong, as they could possibly be a little younger than we initially believed.
The researchers studied a map of the cosmic microwave background of the Universe, which was created with the help of data collected from Planck, and found that these stars are actually younger than previously thought.
Notably, the background of cosmic microwaves is the first light witnessed by the Universe. The previous estimates have proposed it occurring nearly 380,000 years after the Big Bang more than 13 billion years ago. And now, it is spread across the Universe. The same is also seen in the map developed from data offered by Planck satellite.
The map showed that an event known as “reionization” happened later than previously believed. In the beginning sometime after the Big Bang, the scientists explained that the Universe was dark and had no starlight. But eventually, the pieces of matter were brought together due to the gravity, forming the first stars and galaxies. In turn, this led to the creation of radiation that further ionized hydrogen present in the Universe.
The scientists had originally believed that this process of reionization occurred nearly 420 million years ago. But after the careful analysis of the Planck map, the scientists estimate that the reionization event occurred 550 million years after the Big Bang, making the oldest stars in the Universe 100 million years younger than originally believed.
In 2016, the scientists will be validating these measurements following the analysis of data gathered from other satellites and telescopes. The scientists are hopeful their results will confirm this new estimate.
“The Planck’s observations showed stars may be younger than believed, in bearing with other independent astrophysical indicators, and this finding may have major consequences on our attempts to understand the dark components of the Universe,” said SISSA cosmologist Carlo Baccigalupi.
Baccigalupi further said, “Now we’re awaiting data from the high-frequency instrument (HFI), whose maps are mostly constructed by the French team. These additional maps should provide confirmation and a clearer picture of the evidence we detected.”
The Planck satellite was launched by the European Space Agency in the year 2009 in order to observe the features of the cosmic microwave background in the Universe. Although the satellite was deactivated by the space agency in 2013, the scientists continued to study its maps and data. This contributed in making new discoveries, like this one.
