Astronomers Detected A Signal From Stars In The Early Universe
Scientists have announced that they have detected a signal from the very first start in the universe. These are signals from ancient stars that were active within the first 180 million years of the Big Bang. The research team includes members from Arizona State University (ASU), the Massachusetts Institute of Technology (MIT) and the University of Colorado at Boulder.
These researchers used discovered the signal with their Experiment to Detect the Global EoR (Epoch of Reionization) Signature (EDGES) project, funded by the National Science Foundation (NSF) and reported their findings in the March issue of "Nature". The lead investigator on the project is Judd Bowman of the University of Arizona, he said that finding the signal opened a window on the early universe. Bowman also notes that telescopes can't see far enough to directly image stars this ancient.
The scientists were able to see when they turned on in radio waves they have detected. Scientists believe that these early stars were massive, blue, and lived for a brief time. The team was searching for these stars by looking for a change in the background electromagnetic radiation found throughout the universe called cosmic microwave background (CMB).
These dips occur between 65 MHz and 95MHz according to the scientists, but they are hard to detect from Earth due to a crowded radio-wave environment around our planet. The astronomers were able to find the signal thanks to past research indicating these stars released tremendous amounts of UV light that would interact with free-floating hydrogen atoms and absorb the CMB photons.
The team reported in their paper that they saw a clear signal in the radio wave data and detected a fall in CMB intensity. The team also notes that when these early stars died, black holes, supernovae, and other objects left behind continue the ionizing process that the stellar fusion began at the birth of the star. The scientists say that the discovery opens a new chapter in our understanding of how the universe came to be.
SOURCE: Eurekalert