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Scientists use NASA's James . The Webb Space Telescope has observed the farthest galaxy from Earth, at a distance of 13.5 billion light-years, 325 million years after the Big Bang.
The discovery of these ancient galaxies will help unravel the mystery of the origin of the universe and provide important information about the young age of the universe.
Only 325 million years after the birth of the universe, galaxies have already formed, which is only a split second for mankind before the Big Bang.
So, what does this 13.5 billion light-year galaxy mean for humanity?
How will these ancient galaxies help scientists unravel the mystery of the origin of the universe?
1. 13.5 billion light-years old galaxies.
A few days ago, NASA announced that scientists had discovered the farthest galaxy ever observed from Earth through the Webb Space Telescope.
These galaxies have different redshift values, but they are all very high, and they are all more than 10 billion light-years away from Earth.
If the redshift values of these galaxies were converted to distance, then the galaxy farthest from Earth would be 13.5 billion light-years away, and that would be just two poles sandwiched between two numbers.
It is worth mentioning that galaxies at a distance of 13.5 billion light years are not one, but many.
So, when and where were these ancient galaxies born?
And what can scientists learn from these observations of ancient galaxies?
Ranking these observed ancient galaxies, it was found that they were also the oldest galaxy 13.5 billion light-years away from Earth, located in the Powell-Lake Theon-Powell Mountains.
Next up are the Martin Galaxy, which is only 500 million light-years away from Earth, and the Soss Galaxy, which is 12.1 billion light-years away.
So, how were these ancient galaxies discovered?
How can we confirm the distance of these galaxies from Earth?
From the perspective of galaxy observation, neither terrestrial telescopes nor space telescopes are suitable for observing these ancient galaxies, so scientists can only use the "redshift" method to observe these ancient galaxies.
For galaxies, people often use the redshift value to measure the distance of the galaxy, and the larger the redshift value, the faster the galaxy recedes and the farther away.
So, how big are the redshifts of these ancient galaxies?
How can we confirm the redshift values of these ancient galaxies?
2. The redshift value of galaxies.
Since galaxies are usually very far away from Earth, there are many ways to measure the distance of galaxies, but the more common method is to calculate the redshift value of galaxies.
Redshift is a special physical phenomenon that occurs when galaxies are moving, which can change the spectrum of galaxies so that they turn red and can be observed by humans.
In order to confirm the redshift of galaxies, scientists made an observation in 1978, first selected 10 known stars with different redshift values, and then selected 9 stars near the Earth to observe, and obtained the spectra of these stars as standard spectra.
Next, the known and unknown stars were observed, and the spectra of the two samples were obtained, they were attached to the standard spectrum, and the images were plotted.
During the drawing of the image, scientists found that the spectrum of unknown stars shifted in the direction of red, while the spectrum of known stars did not move significantly, indicating that there is a redshift in unknown stars.
On closer analysis, most of the light of unknown stars moves from the middle of the spectrum to both ends, which means that the spectrum of unknown stars is broad, so the redshift of unknown stars is not easy to measure.
In order to better measure the redshift of unknown stars, scientists have proposed a new method to analyze the redshift value of the spectrum by measuring the peak sequence of the main features in the spectrum.
After many observations and studies, it has gradually been discovered that redshift is not an unknown territory, but a universal physical phenomenon, and even objects on Earth have redshifts.
In the 300,000 years after the Big Bang, hydrogen and helium nuclei gradually took shape and fused into protons and neutral atoms, at which point the gases of the universe were diluted to the point where they could transmit light.
This makes the universe transparent, and light can penetrate the gases in the universe, propagate outward, and create a very faint spectrum that is characterized by redshifts.
And the redshift value of this spectrum is about 1100, which is relatively large, which is helpful for observation.
This spectrum is also known as the "extended redshift", and after many observations, scientists have found that the spectrum of the extended redshift has a characteristic, that is, "narrow and high peaks".
By observing the spectra of ancient galaxies, scientists found that their spectra had "narrow, high peaks", and measured the redshift values of these spectra, and finally obtained the oldest galaxies farthest from Earth, and their redshifts.
Among the ancient galaxies observed, the ancient galaxy with a redshift value of 12.63 is about 12.1 billion light-years away from Earth, this galaxy is the closest to Earth, and it also contains a large number of stars, which is a special galaxy.
This galaxy is massive, more than 30 times the mass of Sirius A, and has many massive stars that can easily explode, produce supernovae, and even form black holes.
Over time, the stars of this galaxy will gradually die, leaving some black holes, and the distance of this galaxy is not the farthest, and there are older galaxies with a larger redshift value of 13.20.
Calculating the elongation of an ancient galaxy, it was found that this ancient galaxy is about 13.5 billion light-years away from Earth, which is the farthest ancient galaxy from Earth so far.
The redshift reflected in the spectrum of ancient galaxies is the result of the refraction of light by dark matter in the universe and its eventual propagation to Earth, where telescopes are observed.
3. The Significance of Ancient Galaxies.
The farthest ancient galaxies from the Earth are equivalent to the giant galaxies born 325 million years after the birth of the universe, so what kind of information can these ancient galaxies provide to other galaxies in the universe?
The discovery of these ancient galaxies has given us a new understanding of the "evolutionary history of the universe" from the thriving Milky Way, to active galaxy clusters, to vanishing galaxy clusters, and vanishing ancient galaxies.
Ancient galaxies contain a large number of ancient stars, how did these ancient stars form?
From a theoretical point of view, the formation of these ancient galaxies may be inseparable from 300,000 years after the Big Bang, which is of great significance for the development of the universe and is also a verification of the universe.
According to the existing Big Bang theory, the universe was the Big Bang 14 billion years ago, starting from a singularity, filled with high-energy radiation, thus forming the universe as we see it, and the universe is constantly expanding.
In the 300,000 years after the Big Bang, the universe was warm enough to fuse protons and electrons into hydrogen nuclei, helium nuclei and protons, etc.
In these 300,000 years, the nucleus of hydrogen and electrons collided continuously, and finally the electrons in the gas nucleus were attracted to the protons in the helium nucleus, forming the neutral atoms in the hydrogen nucleus and the subhelium nucleus, and the temperature of the universe gradually decreased.
And in the process of cooling, neutrons, protons and electrons in the universe are gradually formed, and these neutral atoms constitute a quasi-neutral gas cloud, but in the process of cooling, the electrons in the body atoms will be constantly affected by the photons in the universe, and thus become nuclei composed of protons and electrons such as hydrogen and helium.
And in the process of gradually forming neutral nuclei and dense gas clouds, the loaded photons continue to disappear, which forms a gradually transparent universe, so that the existing photons can travel freely in the universe.
The perturbations of matter and dark matter that exist in the universe eventually form the earliest density waves in the universe.
Through the observation and analysis of these neutral nuclei and high-density gas clouds, the disturbances of matter and dark matter in the universe are discovered, and the density of the disturbances is mapped, which can only show the earliest density waves in the universe.
epilogue
These ancient galaxies provide scientists with important information to understand the young age of the universe, helping to test existing theories and unravel the mystery of the origin of the universe.
With the continuous advancement of science and technology, human beings are becoming more and more capable of exploring the universe, and in the future, more distant and ancient galaxies may be discovered, which will bring more information about the origin of the universe.
For the origin and evolution of the universe, scientists may need to combine more fields of knowledge and technical means to conduct multi-faceted research and exploration.
The discovery of these ancient galaxies has also made us more humble to realize our insignificance in the universe, and stimulated human curiosity and desire to explore the mysteries of the universe.
On the road of exploring the universe, the cooperation and joint efforts of scientists around the world are needed to understand the mysteries of the universe more deeply.
Through the study of ancient galaxies, scientists may also be able to discover some new physical laws or phenomena, bringing new breakthroughs and challenges to human scientific understanding.