Rohan was at home with his girlfriend when he came across the galaxy. Late one night in July, he shot to attention after digging through early images from theJWST. It looked at the object and found that it was 300 million years old, older than any other galaxy. He says he called his girlfriend immediately. I told her that it might be the most distant starlight. He got to work after exchanging excited messages with his partner. They published a paper called GLASS-z13. The internet went crazy. Around the world, it was heard. Captain America would share the story on the social networking site.
The discovery of this galaxy, just weeks into full operations, was beyond imagination. The largest, most powerful observatory ever launched from Earth was built to help us understand the universe. Stationed 1.5 million kilometers away from earthly interference, chilled within striking distance of absolute zero by its tennis court–sized sunshade, the telescope was designed to uncover never-before-seen details of Cosmic Dawn. This is the era after the big bang, in which the first stars and galaxies formed. Exotic physics, ranging from dark matter and dark energy to the poorly understood feedbacks between starlight, gas and dust, affect how this process unfolded. It is possible for cosmologists to test their knowledge of the underlying phenomena by looking at the universe from a different point of view.
The initial projections were that the first galaxies would be so small and faint that they wouldn't find many interesting candidates. Things didn't go according to plan. As soon as the telescope's scientists released its first images of the distant universe, they began to find more and more stars that were larger and brighter than expected. The competition for discovery was fierce, with each new day there would be a new claim from one of the research groups. Charlotte Mason is an astronomer at the University of Danes. We didn't expect this.
In the weeks and months after the discovery of early galaxies, theorists and observers alike have been trying to understand them. Is there a flaw in the analysis of the telescope's initial observations? Could they possibly be explained by standard models? Maybe they were the first clues that the universe is more complex than we had thought.
Our understanding of how the orderly universe came about is at stake. The opening chapters of the history of the universe could be changed by the early revelations of the JST. Mark McCaughrean is an advisor for science and exploration at the European Space Agency. You don't know how it's going to break
The Space and Science Telescope Institute (STScI) in Baltimore was the place where the observations of early galaxies were made. The Hubble Space Telescope was five years away from being launched. Illingworth was surprised when his boss asked him to think about what would happen after Hubble. Illingworth said we have more than enough to do on Hubble. He said it would take a long time. The Next Generation Space Telescope (NGST) was renamed to the JWST after a former NASA administrator.
Hubble's capabilities were limited by its observations in visible light. The expansion of the universe widens the wavelength of light known as red shift. The more stretched the light has been, the more distant its source will be. Hubble was unable to see early galaxies because of their high redshifts, which stretched the visible light into IR when it arrived at our telescopes. The NGST has a very large starlight-gathering mirror and would be able to peer much deeper into the universe. According to Illingworth, everyone realized that the telescope would be used to look at early galaxies. The primary science goal was that.
Astronomers pointed Hubble at an empty patch of the sky for 10 days in December 1995 to highlight the need for a telescope. The effort was richly rewarded despite the experts' predictions that the extended observation would be a waste of time and money. The Hubble Deep Field showed that the empty spot was filled with thousands of galaxies, stretching back 12 billion years. Illingworth used to be an astronomer at the University of California, Santa Cruz The Hubble Deep Field shows that the early universe was more crowded and exciting than most people thought. Astronomers wanted more than Hubble did.
After more than two decades of labor, the JWST finally launched on Christmas Day 2021. After reaching its deep-space destination, the telescope's instruments had been put through their paces and the first year of science observations could begin. Some of the telescope's early time was devoted to high impact programs across a range of disciplines from which data would immediately be made public. Two of those, CEERS (the Cosmic Evolution Early Release Science Survey) and GLASS (the Grism Lens–Amplified Survey from Space), would each spend hundreds of hours looking for distant galaxies in the early universe. Perhaps a slightly more ornate version of the Hubble Deep Field was what was expected. Steven Finkelstein from the University of Texas at Austin is the lead on the project.
It was much to the surprise of the astronomer. The most distant known galaxy was spotted in 2015 at a redshift of 11 thanks to a 2009 upgrade to the telescope. A redshift of 11 is a point at the verge of when the universe was formed. There were two teams that independently found a candidate for a more distant galaxy, dubbed GLASS-z13, which was 70 million years away. The researchers relied on redshift estimates to get the results they wanted. It's easier to get these than it is to get a direct measurement of red shift. Our own galaxy is billions of years older than the one suggested by the simplified technique, but it was found to have a mass of stars of a billion suns, less than the one suggested by the simplified technique. Tomasso Treu is an astronomer at the University of California, Los Angeles and the lead on the project.
The record only lasted a short time. After the big bang, a number of galaxy candidates from CEERS and GLASS appeared with redshifts as high as 20 and disklike structures that were not expected to manifest so early in the history of the universe. At a redshift of 10, less than 500 million years after the big bang, another team found evidence for the size of the universe. This model incorporates scientists' best estimates for the properties of dark energy and dark matter which act to dominate the emergence of large-scale Cosmic structures. Dark energy and dark matter are referred to asLambda andCDM. Michael Boylan-Kolchin is a cosmologist at the University of Texas at Austin. It would be a big deal.
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The universe was very hot and dense in the first second after the big bang. As the universe expanded and cooled, the very light elements began to form. The universe was so cold that the first atoms appeared. The conditions were right for the emergence of the first stars when the universe was around 100 million years old. These giant fireballs of mostly hydrogen and helium were not contaminated by heavier elements like modern-day stars. The first suns coalesced in clusters of gas that were invisible to the naked eye. The interactions between the protogalaxies were guided by gravity. It is thought that the process of becoming of the early universe's chaos took about a billion years.
The model is challenged by the discovery of bright galaxies. McGaugh is a cosmologist at Case Western Reserve University in Ohio. We are seeing a few things that are bigger than the universe. Some of these galaxies are shrouded in dust that makes them look dimmer and further away when compared to the rest of the universe. ALMA did not see evidence for large amounts of dust when they looked at GLASS-z13 in August. The astronomer who led the observations thinks we can exclude low-redshift interlopers. The lack of dust makes it difficult for telescopes to match the brilliance of the observations. There is nothing detected. There isn't anything detected. The only thing that can follow-up itself is JWST.
There is an explanation as to why the LCDM model is wrong. The results are hard to get in the standard model of cosmology. It is likely not a small change. We would have to return to the drawing board. The idea that dark matter doesn't exist and can be explained by large-scale fluctuations in gravity is controversial. Such a theory could be supported by JWST's observations. McGaugh is one of the leading proponents of the idea. Others aren't convinced. Jeyhan Kartaltepe is an astronomer at the Rochester Institute of Technology in New York.
It's possible that the early universe had little or no dust, which would make them appear brighter. This scenario could make it difficult to calculate the true mass of the universe. The astronomer at the Scuola Normale Superiore university in Italy has proposed that it could be that the dust from supernovae didn't have enough time to reach us. According to Mason and colleagues, the very bright young galaxies should be the easiest to spot in the early universe. She theorizes that there is something happening in the early universe that makes it easier to form stars.
David Spergel is the president of the Simons Foundation. He believes that high-mass star formation is very efficient in the early universe. Gas pressures are higher. The temperature is going up. It has a huge impact on the environment. Magnetic fields are thought to have arisen earlier in the universe than we thought. Spergel theorizes that magnetic fields could be emerging very early in the universe's history.
When the first data started streaming down, astronomer were eagerly waiting. The people had been working on their pipes for a long time. Scientific papers can be uploaded to arXiv before formal peer review, which is why many chose to publish on the site. Today's peer review is happening in real time on social media. It's science by arXiv. Some people were surprised by the action. Nancy said she expected a lot of activity. I didn't think the amount was that much.
Scientific results were quickly publicized and discussed, but some were afraid. Klaus Pontoppidan said people were rushing things. The gold standard is a peer reviewed paper. Some results may have been affected by early calibration issues. One galaxy at a redshift of 20.4 could be changed to a redshift of 0.7. Adams wants us to calm down a bit. It's too early to say we've broken the universe.
It is unlikely that these issues will eradicate all of the high-redshift galaxies. Finkelstein believes that the early universe is different from what was predicted. The chances are small that we are all wrong. Astronomers are racing to conduct follow-up observations, most of which are looking at high-redshift galaxy candidates. "We thought it was appropriate to ask for a little bit of time to confirm them because of the excitement and importance of these early discoveries."
The population of early galaxies is expected to be greatly increased by observing a wider swath of sky for hundreds of hours. She says there are thousands that will be detected. Future proposals might use the deaths of supersized first stars as markers for their existence. A redshift of 26 is thought to be possible just 120 million years after the big bang. The growing list of high redshift candidates will be followed. It would be incredible to confirm a few of these. It would show we are not being deceived.
Despite all the uncertainties, the rapid exchange of ideas as new discoveries are made and immediately publicized has rejuvenated the astronomy community. "It's been great," said Treu. The community is excited and engaged. Is it time to reexamine our understanding of the dawn of time if we are able to truly believe what we see? Mason is looking into the unknown.
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