Scientists Working to Decode Signal From Earliest Years of Universe
So far, we have very strong suspicions, but no hard answers. One reason is that the light from this period, called the cosmic dawn, is extremely faint, making it nearly impossible to infer the traits of these first cosmic objects, let alone directly observe them.
But that's about to change, according to a team of international astronomers. In a new study published in the journal Nature Astronomy, the astronomers argue that we're on the verge of finally decoding a radio signal that was emitted just one hundred millions years after the Big Bang. Known as the 21 centimeter signal, which refers to its distinct wavelength, this burst of radiation was unleashed as the inchoate cosmos spawned the earliest stars and black holes.
"This is a unique opportunity to learn how the universe's first light emerged from the darkness," said study co-author Anastasia Fialkov, an astronomer from the University of Cambridge in a statement about the work. "The transition from a cold, dark universe to one filled with stars is a story we're only beginning to understand."
After several hundred thousand years of cooling following the Big Bang, the first atoms to form in the universe were overwhelmingly neutral hydrogen atoms made of one positively charged proton and one negatively charged electron.
But the formation of the first stars unbalanced that. As these cosmic reactors came online, they radiated light energetic enough to reionize this preponderance of neutral hydrogen atoms. In the process, they emitted photons that produced light in the telltale 21 centimeter wavelength, making it an unmistakeable marker of when the first cosmic structures formed. Deciphering these emissions would be tantamount to obtaining a skeleton key to the dawn of the universe.
And drum roll, please: employing the Radio Experiment for the Analysis of Cosmic Hydrogen telescope, which is currently undergoing calibration, and the enormous Square Kilometer Array, which is under construction Australia, the researchers say they've developed a model that can tease out the masses of the first stars, sometimes dubbed Population III stars, that are locked inside the 21 centimeter signal.
While developing the model, their key revelation was that, until now, astronomers weren't properly accounting for the impact of star systems called x-ray binaries among these first stars. These are systems where a black hole or neutron star is stripping material off a more ordinary star that's orbiting it, producing light in the x-ray spectrum. In short, it appears that x-ray binaries are both brighter and more numerous than what was previously thought.
"We are the first group to consistently model the dependence of the 21-centimeter signal of the masses of the first stars, including the impact of ultraviolet starlight and X-ray emissions from X-ray binaries produced when the first stars die," said Fialkov. "These insights are derived from simulations that integrate the primordial conditions of the universe, such as the hydrogen-helium composition produced by the Big Bang."
All told, it's another promising leap forward in the field of radio astronomy, where recent advances have begun to reveal an entire "low surface brightness" universe — and a potentially profound one as well, with the promise to illuminate our understanding of the cosmic dawn as never never before.
"The predictions we are reporting have huge implications for our understanding of the nature of the very first stars in the universe," said co-author Eloy de Lera Acedo, a Cambridge astronomer and a principal investigator of the REACH telescope. "We show evidence that our radio telescopes can tell us details about the mass of those first stars and how these early lights may have been very different from today's stars."
More on astronomy: Scientists Investigating Small Orange Objects Coating Surface of the Moon
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
4 hours ago
- Yahoo
Stunning pictures capture tonight's incredible moon
Stunning pictures show the incredible Sturgeon Moon lighting up the night sky tonight. Bolton Camera Club member Ian Bleakley snapped these beautiful pictures this evening. The 2025 Sturgeon Moon will be available to see this weekend, and it is the last full moon in summer this year. (Image: Ian Bleakley) It will rise again tomorrow, Sunday, August 10, in the southeast between 8pm and 9pm. he Sky at Night Magazine also says that if you view the Sturgeon Moon from its rise, then you will witness an optical effect called the "Moon Illusion". READ MORE: Planetary parade: When to see the rare event in the UK skies How to see 2025 August Sturgeon Moon in UK this weekend Pictures of the Northern Lights above Bolton It says: "It happens when the Moon is low on the horizon and looks much bigger than normal. "It's likely caused by foreground objects like buildings and trees appearing tiny in comparison to the bright full Moon, thereby making the Moon itself look huge." The Sturgeon Moon is not the only exciting sky event taking place this month. (Image: Ian Bleakley) Next week, the Perseids Meteor Shower peaks, which could see more than 100 per hour, meaning August 12 and 13 are the best times to see it. It has been active since July 17 and will continue until August 24. (Image: Ian Bleakley) Then, later in August, there will be a planetary paradewith six planets visible in the night sky. Mercury, Jupiter, Venus, and Saturn will be visible to the naked eye, while Uranus and Neptune can be spotted through binoculars or a small telescope. It will take place on the morning of August 18, with the alignment visible for about 45 minutes before sunrise at around 6am, according to The Farmers' Almanac.
Yahoo
7 hours ago
- Yahoo
Wild New Theory Suggests Gravitational Waves Shaped The Universe
Just as ocean waves shape our shores, ripples in space-time may have once set the Universe on an evolutionary path that led to the cosmos as we see it today. A new theory suggests gravitational waves – rather than hypothetical particles called inflatons – drove the Universe's early expansion, and the redistribution of matter therein. "For decades, we have tried to understand the early moments of the Universe using models based on elements we have never observed," explains the first author of the paper, theoretical astrophysicist Raúl Jiménez of the University of Barcelona. "What makes this proposal exciting is its simplicity and verifiability. We are not adding speculative elements, but rather demonstrating that gravity and quantum mechanics may be sufficient to explain how the structure of the cosmos came into being." Related: Dark Matter May Have Existed Before The Big Bang, Study Finds We don't know for certain how the very earliest stages of the Universe unfolded following the Big Bang some 13.8 billion years ago. All scientists can do at this point is come up with theories that fit the physics of the Universe we do observe. Those theories are pretty good, but there are clear shortcomings. Take the JWST's discovery of large numbers of massive galaxies earlier in the Universe than cosmologists expected, for example. The currently accepted timeline of the Universe's evolution involves a period of rapid expansion, or inflation, just after the Big Bang. From a single, one-dimensional point of infinite density – a singularity, the mathematical description of the Universe just before the Big Bang – the Universe rapidly inflated, puffing up with a hot plasma soup that cooled to form matter. The inflaton is a speculative particle or quantum field that scientists use to explain cosmological inflation and the surprising smoothness of the cosmos. In theory, the particle drives the rapid expansion of the Universe while still allowing for variations in the density of the plasma soup that eventually condense into black holes, galaxies, stars, and all the other bits and bobs of matter scattered throughout the Universe. Despite our best efforts, however, physicists have found no other evidence that supports the existence of the inflaton. Jiménez and his colleagues wanted to know if there's another way – if we can explain the early evolution of the Universe using different parameters that rely less on speculative elements. They started with a very simplified model of the real Universe consistent with general relativity and current observations of the expansion of the Universe, called de Sitter space. Within this field, quantum fluctuations in space-time – that is, gravitational waves – can be generated by a type of turbulence called tensor perturbations. Gravitational waves are thought to fill the Universe today. They're the ripples generated in space-time by massive disruptions. The ones we can detect currently are generated by collisions between massive, dense objects such as neutron stars and black holes, but physicists believe the entire Universe is ringing with a constant background hum of gravitational waves too large for us to be able to detect (yet). The researchers found that the gravitational waves generated by tensor perturbations in their space-time model could create density variations in the primordial plasma on their own, as well as drive the early expansion of the Universe. Eventually, these variations would create clumps dense enough to collapse under gravity and form the seeds of the early Universe – the very first stars and galaxies and black holes. It's such an elegant solution, and removes the reliance on hypotheticals as the driving force behind the early evolution of the entire Universe, although further work is needed to verify it, of course. Nevertheless, "Our proposed mechanism could remove the need for a model-dependent scenario: the choice of a scalar field, as the inflaton, to drive inflation," the researchers write. Their work has been published in Physical Review Research. Related News August's Full Sturgeon Moon Is Here: What It Is And How to See It An Astrophysicist Proposes We Send a Spacecraft to Visit a Black Hole You're More Likely to Die From an Asteroid Than Rabies, Scientists Find Solve the daily Crossword
Yahoo
9 hours ago
- Yahoo
Shroud of Turin study unlocks new, key details of Jesus' burial — reinforcing accuracy of biblical accounts
The blood, sweat and tears on these threads are still — sorta — shrouded in mystery. New findings provide more evidence on what Jesus might have been buried in after he was crucified. A recent study conducted by Johns Hopkins-trained immunologist Kelly Kearse suggests that it is, in fact, possible that Jesus was buried unwashed, wrapped in spices and linen — which is believed to be the Shroud of Turin — as biblical narratives suggest. The research, published in the International Journal of Archaeology in June 2025, specifically referenced a garment where evidence of blood clotting was found. Among the key discoveries from the study, visible rings around bloodstains — or serum halos — were found on the linen when examined with a UV light. Kearse tested multiple samples — mimicking blood conditions after death, including thickened consistency and increased acidity. The expert also studied the way that blood transfers to textiles in various conditions and compared it to the bloodstains on the Shroud of Turin with a microscope. The immunologist, who has studied the shroud for years, believes that this is a revealing element that can help provide context for Jesus' burial conditions — specifically, for what he calls 'the washing hypothesis,' according to the study. A previous study of the shroud, done in 1998, concluded that if a body was indeed enveloped in the cloth, it was washed before burial. The serum halos are only visible if wounds begin to clot before touching the surface. If the body were washed or cleaned, the stains wouldn't be as prominent. Biblical passages suggest that the Jewish burial customs observed prohibited the washing of bodies that suffered violent deaths, with the belief that blood should not be separated from the physical body in the case of murder. Countless studies about the Shroud of Turin have been conducted across the centuries since it surfaced, and skeptics have suggested various theories about the authenticity of the shroud itself and the biblical account. One such recent inquiry into the iconic cloth is that it was not the messiah's post-mortem mode, but rather, it was used to swathe an artist's chiseled Christ-like copy, a study suggested.
