First stars not as old as we thought
DOI: 10.1063/PT.5.028622
New Scientist : The first stars developed in the early universe about 150 million years later than previously estimated, according to a new analysis of data collected from Planck. The space-based telescope surveyed the cosmic microwave background from 2009 through 2012. Before the first stars formed, normal matter in the universe consisted of opaque clouds. Only when the starlight ionized those atoms did the universe become transparent. This latest analysis also confirmed Planck‘s previous measurements of the amount of ordinary matter, dark matter, and dark energy in the universe and continued to rule out the possibility of a ghostly particle called a sterile neutrino . The remaining mystery that Planck hasn’t confirmed is the existence of primordial gravitational waves.