Using a compact radio antenna 10 years in the making, Scientists have discovered the confirmation of the oldest suns in the known universe. They’ve published their findings in Nature.
Whenever we look at the stars, we see them as they used to be, not as they are now. The reason behind this is that the light takes time for traveling from its source to our eyes. With the most powerful enough telescopes, we can directly see the very oldest stars present in the universe. Unfortunately, those telescopes don’t exist.
Instead, we have to rely on indirect proofs. Hence, that’s what a team of astronomers from Arizona State University (ASU), the Massachusetts Institute of Technology (MIT), and the University of Colorado at Boulder set out to find. Their search was part of the Experiment to Detect the Global EoR (Epoch of Reionization) Signature (EDGES) project, that is funded by the National Science Foundation (NSF).
The researchers assumed that the earliest stars likely changed the universe’s background in concern with the electromagnetic radiation, that is also known as cosmic microwave background (CMB). Moreover, they knew what they were looking for a small change in the intensity of CMB radio signals between certain wavelengths; furthermore, finding it wasn’t going to be easy, considering everything else going on in the universe.
“Sources of noise can be 10,000 times brighter than the signal — it’s like being in the middle of a hurricane and trying to hear the flap of a hummingbird’s wing,” Peter Kurczynski, an NSF program director, noted in a press release.
Based on the previous researches, the team of the Scientists also knew that the universe’s earliest stars released a quite large quantity of ultraviolet (UV) light. As soon as this light interacts with hydrogen atoms, it immediately absorbs CMB photons, later leaving a signal in radio frequencies; that’s an indication of the stars are forming.
Using a customized radio antenna in the Australian desert, the team collected radio wave data until, finally, they found what they have been looking for: this could be a clear dip in CMB intensity. This dip, somwhere indicated that the ancient suns first emerged about 180 million years post-Big Bang. Later, for several years the researchers kept working on this- the continuously checked and rechecked the data before concluding its validity.
“Finding this minuscule signal has opened a new window on the early universe,” said lead investigator Judd Bowman, an ASU cosmologist, in the press release. “It’s unlikely we’ll be able to see any earlier into the history of stars in our lifetime.”
This discovery of Scientists helps us in solving one of its greatest mysteries: the nature of dark matter than just giving us a glimpse of the universe’s earliest stars.
The signal at the center of the EDGES project was twice as intense as expected, indicating that the absorbing hydrogen atoms were colder than researchers thought they’d be. One possible explanation could be an interaction with dark matter.
“If that idea is confirmed, then we’ve learned something new and fundamental about the mysterious dark matter that makes up 85 percent of the matter in the universe,” said Bowman. “This would provide the first glimpse of physics beyond the standard model.”
Even without the possible dark matter connection, the discovery is revolutionary. The EDGES project team’s follow-up projects, designed to build off this remarkable research, are already in the works.