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A single universal equation can closely approximate the frequency of wingbeats and fin strokes made by birds, insects, bats and whales, despite their different body sizes and wing shapes, researchers report in a new study.

Large Language Models behind popular generative AI platforms like ChatGPT gave different answers when asked to respond to the same reasoning test and didn't improve when given additional context, finds a new study.

New partitioning coefficients of first-transition row elements, Ga and Ge between olivine and silicate melt have been reported. New high-temperature experiments have investigated the effects of oxygen fugacity and iron content on these partition coefficients. This newly compiled dataset offers insights into interpreting trace elements found in olivine phenocrysts within lunar basalts, shedding light on the deep interior composition of the Moon.

Scientists are getting closer to detecting bushfires in record time, thanks to cube satellites with onboard AI now able to detect fires from space 500 times faster than traditional on-ground processing of imagery.

A groundbreaking method of detecting high-frequency gravitational waves (HFGWs) has been proposed. The team's innovative approach may enable the successful detection of HFGWs by utilizing existing and technologically feasible astronomical telescopes in planetary magnetosphere, opening up new possibilities for studying the early universe and violent cosmic events in an effective and technically viable way.

Scientists have detected what they believe to be a neutron star spinning at an unprecedentedly slow rate -- slower than any of the more than 3,000 radio emitting neutron stars measured to date.

Car tires contain hundreds of chemical additives that can leach out of them. This is how they end up in crops and subsequently in the food chain. Researchers have now detected these chemical residues in leafy vegetables for the first time. Although the concentrations were low, the evidence was clear, a finding that is also known for drug residues in plant-based foods.

Babies' brains are not as immature as previously thought, rather they are using the period of postnatal 'helplessness' to learn powerful foundation models similar to those underpinning generative Artificial Intelligence, according to a new study.

A collaborative team of researchers has made a cracking discovery with the potential to make a significant impact in the sustainable recovery of rare earth elements (REEs), which are in increasing demand for use in green energy technologies. The team found that humble eggshell waste could recover REES from water, offering a new, environmentally friendly method for their extraction.

A collaborative team of researchers has made a cracking discovery with the potential to make a significant impact in the sustainable recovery of rare earth elements (REEs), which are in increasing demand for use in green energy technologies. The team found that humble eggshell waste could recover REES from water, offering a new, environmentally friendly method for their extraction.

Many managers are currently seeking a balance between digital and face-to-face communication. A recent study shows that top IT industry managers have different views on when and for what purposes face-to-face communication in the workplace is needed.

A team of researchers has developed a new method for target DNA sequence amplification, testing and analysis.

For many parents, it can feel like curbing kids' screen use is a losing battle. But new research has found the parenting practices that work best to curb screen time and addictive screen behavior: restricting screens in bedrooms and at mealtimes and modeling healthy practices at home.

Fusion researchers have successfully deployed machine learning methods to suppress harmful plasma edge instabilities without sacrificing plasma performance.

Fusion researchers have successfully deployed machine learning methods to suppress harmful plasma edge instabilities without sacrificing plasma performance.

Almost a century ago, the discovery of antibiotics like penicillin revolutionized medicine by harnessing the natural bacteria-killing abilities of microbes. A study suggests that natural-product antibiotic discovery is about to accelerate into a new era, powered by artificial intelligence (AI).

Researchers have developed a low-cost, energy-efficient method for making materials that can capture carbon dioxide directly from the air. Researchers used a method similar to charging a battery to instead charge activated charcoal, which is often used in household water filters.

Researchers have discovered how networks of neurons in fruit flies transform simple brain signals into coordinated actions. This sheds light on the neural mechanisms underlying complex behaviors for potential application in robotics.

A rare exoplanet that should have been stripped down to bare rock by its nearby host star's intense radiation somehow grew a puffy atmosphere instead -- the latest in a string of discoveries forcing scientists to rethink theories about how planets age and die in extreme environments. Nicknamed 'Phoenix' for its ability to survive its red giant star's radiant energy discovered planet illustrates the vast diversity of solar systems and the complexity of planetary evolution -- especially at the end of stars' lives.

When the James Webb Space Telescope was launched at the end of 2021, we expected stunning images and illuminating scientific results. So far, the powerful space telescope has lived up to our expectations. The JWST has shown us things about the early Universe we never anticipated.

Some of those results are forcing a rewrite of astronomy textbooks.

Textbooks are regularly updated as new evidence works its way through the scientific process. But seldom does new evidence arrive at the speed the JWST is delivering it. Chapters on the Early Universe are in need of a significant update.

At the recent 2024 International Space Science Institute (ISSI) Breakthrough Workshop in Bern, Switzerland, a group of scientists summed up some of the telescope’s results so far. Their work is in a new paper titled “The First Billion Years, According to JWST.” The list of authors is long, and those authors are quick to point out that an even larger group of international scientists played a role. It takes an international scientific community to use JWST observations and advance the “collective understanding of the evolution of the Early Universe,” as the authors write.

The Early Universe is one of the JWST’s primary scientific targets. Its infrared capabilities allow it to see the light from ancient galaxies with greater acuity than any other telescope. The telescope was designed to directly address confounding questions about the high-redshift Universe.

The following three broad questions are foundational issues in cosmology that the JWST is addressing.

What are the Physical Properties of the Earliest Galaxies? The JWST captured these images of 19 face-on spiral galaxies as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program. The telescope has shown us that early galaxies were much larger than expected. Image Credit: NASA, ESA, CSA, STScI, J. Lee (STScI), T. Williams (Oxford), PHANGS Team, E. Wheatley (STScI)

The early Universe and its transformations are fundamental to our understanding of the Universe around us today. Galaxies were in their infancy, stars were forming, and black holes were forming and becoming more massive.

The Hubble Space Telescope was limited to observations at about z=11. The JWST has shoved that boundary aside. Its current high-redshift observations have reached z=14.32. Astronomers think that the JWST will eventually observe galaxies at z=20.

The lookback time of extragalactic observations by their redshift up to z=20. Image Credit: By Sandizer – Own work, CC0, https://commons.wikimedia.org/w/index.php?curid=140812763

The first few hundred million years after the Big Bang is called the Cosmic Dawn. JWST showed us that ancient galaxies during the Cosmic Dawn were much more luminous and, therefore, larger than we expected. The galaxy the telescope found at z=14.32, called JADES-GS-z14-0, has several hundred million solar masses. “This raises the question: How can nature make such a bright, massive, and large galaxy in less than 300 million years?” scientists involved with JWST Advanced Deep Extragalactic Survey (JADES) said in a NASA post.

It also showed us that they were differently shaped, that they contained more dust than expected, and that oxygen was present. The presence of oxygen indicates that generations of stars had already lived and died. “The presence of oxygen so early in the life of this galaxy is a surprise and suggests that multiple generations of very massive stars had already lived their lives before we observed the galaxy,” the researchers wrote in the post.

“All of these observations, together, tell us that JADES-GS-z14-0 is not like the types of galaxies that have been predicted by theoretical models and computer simulations to exist in the very early universe,” they continued.

What is the Nature of Active Galactic Nuclei in Early Galaxies? This image shows Hercules A, a galaxy in the Hercules constellation. The X-ray observations show superheated gas, and the radio observations show jets of particles streaming away from the AGN at the center of the galaxy. The jets are almost 1 million light-years long. Image Credits: X-ray: NASA/CXC/SAO; visual: NASA/STScI; radio: NSF/NRAO/VLA.

Active Galactic Nuclei (AGN) are Supermassive Black Holes (SMBHs) that are actively accreting material and emitting jets and winds.

Quasars are a sub-type of AGN that are extremely luminous and distant, and quasar observations show that SMBHs were present in the centers of galaxies as early as 700 million years after the Big Bang. But their origins were a mystery. Astrophysicists think that these early SMBHs were created from black hole “seeds” that were either “light” or “heavy.” Light seeds had about 10 to 100 solar masses and were stellar remnants. Heavy seeds had 10 to 105 solar masses and came from the direct collapse of gas clouds.

The JWST’s ability to effectively look back in time has allowed it to spot an ancient black hole at about z=10.3 that contains between 107 to 108 solar masses. The Hubble Space Telescope didn’t allow astronomers to measure the stellar mass of entire galaxies the way that the JWST does. Thanks to the JWST’s power, astronomers know that the black hole at z=10.3 has about the same mass as the stellar mass of its entire galaxy. This is in stark contrast to modern galaxies, where the mass of the black hole is only about 0.1% of the entire stellar mass.

Such a massive black hole existing only about 500 million years after the Big Bang is proof that early BHs originated from heavy seeds. This is actually in line with theoretical predictions. So, the textbook authors are now in a position to remove the uncertainty.

When and How Did the Early Universe Become Ionized? This graphical timeline of the Universe shows where the Epoch of Reionization fits in. Image Credit: By NASA – NASA, Public Domain, https://commons.wikimedia.org/w/index.php?curid=6272041

“We know that hydrogen reionization happened, but exactly when and how it happened has been a major missing piece in our understanding of the first billion years.”

From “The First Billion Years According to the JWST.”

We know that in the early Universe, hydrogen became ionized during the Epoch of Reionization (EoR). Light from the first stars, accreting black holes, and galaxies heated and reionized the hydrogen gas in the intergalactic medium (IGM), removing the dense, hot, primordial fog that suffused the early Universe.

Young stars were the primary light source for the reionization. They created expanding bubbles of ionized hydrogen that overlapped one another. Eventually, the bubbles expanded until the entire Universe was ionized.

This was a critical phase in the development of the Universe. It allowed future galaxies, especially dwarf galaxies, to cool their gas and form stars. But scientists aren’t certain how black holes, stars, and galaxies contributed to the reionization or the exact time frame in which it took place. “We know that hydrogen reionization happened, but exactly when and how it happened has been a major missing piece in our understanding of the first billion years,” the authors of the new paper write.

Astronomers knew that Reionization ended about one billion years after the Big Bang, at about redshift z=5-6. But before the JWST, it was difficult to measure the properties of the UV light that caused it. With the JWST’s advanced spectroscopic capabilities, astronomers have narrowed down the parameters of reionization. “We have found spectroscopically confirmed galaxies up to z = 13.2, implying reionization may have started just a few hundred million years after the Big Bang,” the authors write.

JWST results also show that accreting black holes and their AGN likely contributed no more than 25% of the UV light that caused reionization.

These results will require some rewriting of textbook chapters on the EOR, even though there are still lingering questions about it. “There is still significant debate about the primary sources of reionization, in particular, the contribution of faint galaxies,” the authors write. Even though the JWST is extraordinarily powerful, some distant, faint objects are beyond its reach.

The James Webb Space Telescope: humanity’s new favourite science instrument. Image Credit: NASA

The JWST is not even halfway through its mission and has already transformed our understanding of the Universe’s first one billion years. It was built to address questions around the Epoch of Reionization, the first black holes, and the first galaxies and stars. There’s definitely much more to come. Who knows what the sum total of its contributions will be?

As an astronomy writer, I’m extremely grateful to all of the people who brought the JWST to fruition. It took a long time to build, cost a lot more than expected, and was almost cancelled by Congress. Its perilous path to completion makes me even more grateful to be covering its results. The researchers using JWST data are clearly grateful, too.

“We dedicate this paper to the 20,000 people who spent decades to make JWST an incredible discovery machine,” they write.

The post The JWST is Re-Writing Astronomy Textbooks appeared first on Universe Today.