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New JWST Image Shows That Grand Spiral Galaxies had Already Formed 11 Billion Years ago

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For the first time this week, photos from the James Webb Space Telescope (JWST) revealed that stellar bars were present in some galaxies as far back as 11 billion years ago. Stellar bars are a defining feature of about two-thirds of all spiral galaxies in the Universe, including our own Milky Way. The discovery has implications for astronomers’ understanding of galactic evolution, indicating that bars form very quickly and may persist for much of a galaxy’s lifespan, influencing its shape and structure.

 

Stellar bars are regions of intense star formations that radiate out from a galaxy’s core. Through the motion of inner orbiting stars, dust, and gas clouds, they build up as a wave of dense material that perpetuates itself and spreads slowly outward while pulling raw material inwards. These regions become stellar nurseries that churn out new stars at a rapid pace.

Six barred galaxies as seen by JSWT, as they would have looked in the early universe, between 8.4 and 11 billion years ago (Gyr). Credit: NASA/CEERS/University of Texas at Austin.

The new JWST images, presented by The University of Texas at Austin on January 5th, show six barred spiral galaxies over 8.4 million years old, two of which are older than 11 billion years (the oldest galaxy ever seen is around 13.4 billion years old).

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Most of these galaxies were previously imaged by the Hubble Space Telescope, like EGS-23205, pictured below. (EGS stands for Extended Groth Strip, a region of the sky that has been extensively images and studied by international surveys). However, in the Hubble images, the bars are largely obscured.

Galaxy EGS23205, as seen by Hubble (left, taken in the near-infrared filter), and JWST (right, mid-infrared image). Credit: NASA/CEERS/University of Texas at Austin.

JWST has an advantage over Hubble in observing extremely old and distant galaxies, partly because its larger mirror can collect more light from distant, dim objects. But it also has an advantage due to its use of infrared rather than optical wavelengths. Light from older and more distant objects is ‘red-shifted’ along the electromagnetic spectrum, meaning that JWST’s detectors can pick them up better than Hubble can.

Infrared is also very effective at seeing through gas and dust, enabling JWST to pick out the stellar nurseries in the bars which would otherwise be obscured.

Shardha Jogee, professor of astronomy at The University of Texas at Austin, explained the implications of these early forming bars for models of galactic evolution:

The location of the Extended Groth Strip (EGS) in the night sky. The galaxies newly observed by JWST lie within the EGS. Image Credit: NASA, ESA, M. Davis (University of California, Berkeley), S. Faber (University of California, Santa Cruz), and A. Koekemoer (STScI).

“Bars solve the supply chain problem in galaxies,” Jogee says. “Just like we need to bring raw material from the harbor to inland factories that make new products, a bar powerfully transports gas into the central region where the gas is rapidly converted into new stars at a rate typically 10 to 100 times faster than in the rest of the galaxy…This discovery of early bars means galaxy evolution models now have a new pathway via bars to accelerate the production of new stars at early epochs.”

The new images are part of the Cosmic Evolution Early Release Science Survey (CEERS), and their initial findings have been accepted for publication in The Astrophysical Journal Letters.

JWST is ushering in an exciting time for astronomers, and this was a promising start to 2023.

“I took one look at these data, and I said, ‘We are dropping everything else!’” says Jogee.

 

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Quebec zoo examined animal behaviour during last week's total solar eclipse – CityNews Montreal

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As darkness settled during last week’s total solar eclipse, Japanese macaques turned their backs to the sun and red crowned cranes went uncharacteristically quiet.

But the Himalayan black bears just slept as if nothing was happening. 

A Quebec zoo took advantage of last Monday’s total solar eclipse to study the behaviours of some of its animals. The zoo’s research and conservation department was approached by an astrophysics professor from the Université du Québec à Montréal about taking part in an animal behaviour study and collecting data on how they reacted during the rare phenomenon.

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Granby Zoo is located in the province’s Estrie region, which had among the best views of rare total solar eclipse in southern Quebec. While humans were enthralled, few studies have been carried out on animal reactions during the rare event.

Chelsey Paquette, conservation coordinator at Granby Zoo, about 65 kilometres east of Montreal, said the zoo jumped at the chance to be involved. A study will be published to present the findings.

“What we can take from it is that definitely luminosity does have an effect on animals and whatever data we find, the conclusions we can take from the species at the zoo can probably be extrapolated to wildlife species as well,” Paquette said. 

“It’s a rare event, so to collect data during a rare event to better understand how luminosity in the presence of the sun can influence animals is quite unique.”

Observers logged the animals’ activities over two days in the week leading up to the eclipse, between 2 and 5 p.m. during the event itself and for another two days later in the week following it. 

The reactions they saw varied.

The Japanese macaques, a monkey species native to Japan, for example, had a reaction to the eclipse that was the opposite of what the researchers anticipated.

“We expected them to be agitated and to group together and want to go to the nighttime habitats for example,” Paquette said. “But during the totality of the eclipse, it was almost like they stopped vocalizing, they stopped all their movements and they just turned their backs to the sun and were just Zen and calm.”

The Red-crowned cranes are normally quite vocal, but also went quiet when the eclipse reached totality, Paquette said.

The male red panda spent most of the afternoon walking around his enclosure in the afternoon but as soon as the eclipse came, he climbed up a tree and went and slept with the female during the entire totality, which she said was unusual.

Paquette was assigned to the Himalayan black bears.

“We thought they would probably move towards their nighttime habitat when the sun was completely covered, it was pretty much like nighttime,” Paquette said. “But the bears just continued to sleep throughout the afternoon and they didn’t really seem to be influenced by the solar eclipse.”

Tahrs, ungulates that are related to goats and sheep, normally spend their afternoons calmly resting, with half of those in the zoo usually lying down.

“But during the eclipse, actually 100 per cent of these animals were standing up, they were walking around, so this was actually quite a drastic change for them,” Paquette said.

The zoo tried to collect data on a wide range of species, including some that are typically active during the day and others that tend to be more nocturnal. One observation was that prey species had a stronger reaction to the eclipse than predator species, Paquette said.

“It’s just interesting, these little observations that we were able to make,” Paquette said.

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Is space science worth the money?

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Why space science is worth the money

Although governments around the world understand the value of basic science, it can be hard to prioritize its funding given the variety of competing needs within a nation. NASA’s space science programs in 2024 amount to roughly 0.1% of annual U.S. spending, which represents a decrease in recent years. As such, space science sometimes needs to rely on justifications beyond its intrinsic value.

In a famous 2007 speech, former NASA Administrator Mike Griffin differentiated between the “real” and “acceptable” reasons for exploring space. “Acceptable” reasons for space exploration are logical, quantifiable, policy-friendly justifications. The “real” reasons, on the other hand, are intuitive, grand, emotional, and difficult to quantify. Both types of reasons are valid, and together they help explain why space science is worth the investment.

Some of the “acceptable” reasons for space science involve economic payoffs. Research has found that countries that invest more in basic research, including space science, see a return on investment in their overall economic performance and growth. This effect is dispersed throughout the economy through highly skilled, well-paying jobs. It also has an indirect effect on the economy: Discovery leads to technology and invention, which leads to new products, jobs, and industries. While technology development isn’t the primary goal of space science, this kind of progress would eventually stagnate if basic scientific research were neglected.

Another policy-friendly reason to invest in space science is that many scientific missions are internationally collaborative and contribute to allyship with other nations. There is also the very pragmatic goal of understanding Earth, the planet on which we all depend, by studying other planets and their histories. Venus, for example, was once an Earth-like world that eventually devolved into an inhospitable hellscape. By understanding that planet, we can work to prevent a similar fate for our own.

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But, as Griffin explains, much of what humans do, from falling in love with one’s spouse to enjoying one genre of music more than another, is based on emotional and intuitive motivations. This is a human characteristic, and it plays out in our drive to understand the Universe and our place within it. In many ways, this is why we invest in space science: we want to go to new places and discover new things, witness the beauty and majesty of the Cosmos, understand where we came from and what might be possible in our future, and achieve astonishing feats.

Awe, wonder, and inspiration are among the “real” reasons for conducting space science. These are benefits that people can enjoy but that are impossible to quantify or justify on a budget balance sheet. Still, they are some of the most powerful motivators for studying the Universe and our place within it.

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Space exploration: A luxury or a necessity? – Phys.org

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Space exploration: A luxury or a necessity?

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This photo provided by NASA shows, from left to right, Reid Wiseman, Victor Glover, Christina Koch and CSA (Canadian Space Agency) astronaut Jeremy Hansen during a test at the Kennedy Space Center in Florida on Sept. 20, 2023. These astronauts are scheduled to fly to the moon in 2025. Credit: NASA

“Oh, come on Daniel, space travel is so expensive, and pointless!” These were the words of my friend Max, during a Christmas party where I was discussing my thesis project: studying places on Earth where the living conditions are so extreme, they could hold lessons for future space missions.

This disdainful attitude toward space research is actually quite common.

Space exploration is currently booming. Just think of the Artemis missions, SpaceX’s ambitious plans for Mars, the deployment of the James Webb telescope or the recent “race to the moon.”

A number of large-scale projects are getting the green light now, mainly from NASA, including the Artemis II mission that will carry four astronauts to the moon, which will have Canadian astronaut Jeremy Hansen aboard. This will be a first since 1972. Incredibly, it’s been 50 years since the last human mission to Earth’s natural satellite.

Although many people find space exploration inspiring, others are skeptical and even angered by what they see as an unjustifiable waste of resources and money on an activity that only spreads pollution to another place. This sums up the feelings of my friend Max.

In this article, I will try to prove him wrong.

Humans are explorers first

My great curiosity has led me to travel to extreme places so I can study them. But I am not the only one with this desire to explore.

In my Grade 9 history class, my teacher stood on top of her desk and, with a grave and serious tone, went on to act out Jacques Cartier’s arrival in North America in her own, colorful style. A few years earlier, I had learned about how the first humans left their caves to climb mountains. One hundred and thirty years ago, humans sailed further and further south until they saw the glacial landscapes of Antarctica for the first time. At the same time, humans were attempting to dominate the skies and aiming for the beyond with planes and rockets—which is how we got to the moon.

What is the common denominator in our history? Exploration, of course.

Human nature is characterized by a propensity to travel, to look further and to discover. We are all curious by nature. If we stop wanting to explore, we stop being human.

The Earth has rings

So, my friend Max, let me invite you outside. It’s a beautiful, starry night with no moon. It’s a bit cold, but at least the atmosphere isn’t too humid, which makes the sky more transparent. We can see stars flickering. Some are blue, others are red. And the more our eyes adapt, the more the sky reveals its secrets.

Suddenly, something else stands out. It’s another light, but it’s not flashing, and it’s moving quite quickly. A shooting star? No, the atmosphere would have burned it up in a few seconds.

It’s a satellite, one of thousands that orbit the Earth like rings. These satellites are a direct consequence of space exploration. We would be living in a completely different world without them.

Space exploration is not a luxury, it's a necessity
Satellites are like our planet’s artificial rings (artistic view). Credit: European Space Agency, 10.1126/science.abi6892

Indeed, not an hour goes by in our lives when we don’t use a satellite.

On the one hand, you would likely have gotten lost on your way here, Max, because there would have been no GPS to show you which exit to take. And secondly, I wouldn’t have been able to help you find your way because there would be no wifi. We can push our thinking even further; agriculture, environmental monitoring, communications, the weather, even banks, all of these depend on satellites.

But how does this work? You have to understand that these satellites move so quickly they actually circle the Earth several times a day. Combined with a very large workforce, they provide a complete view of the globe. From the middle of the oceans to the highest mountains and the almost inaccessible poles, we have eyes everywhere. By drawing on this vast quantity of observations, we obtain data on changes to the earth’s surface, the spread of forest fires, the movement of winds, the melting of ice and many other things, while enabling global communication and credit card transactions.

Space exploration was the trigger that enabled us to develop and operate these technologies. And it doesn’t stop there.

Two birds, one stone

The practice of medicine in also benefits from space exploration. It’s not easy for communities in remote areas to access health care, especially since hospitals don’t always have the sophisticated equipment they need.

If you think about it, when astronauts explore space, they become a small population in a very, very remote region. It’s true. What happens if someone has a really bad stomach ache? Or breaks an arm? They don’t have time to come back home for treatment, so we have to react, and quickly.

Scientific research in telemedicine has developed to address this important issue, producing a number of innovative technologies. And if these are useful for astronauts, why not use them for rural populations, too?

A few years ago, three Québec researchers from different universities were working on a tiny probe that could rapidly analyze and diagnose a blood sample.

Although some prototypes are not yet on the market, others are already in widespread use, such as the ultrasound scanner designed by NASA. This scanner takes precise photos of organs and bones that can be transmitted to a doctor, who will then have crucial information on hand to recommend treatments.

In a way, space exploration provides us with opportunities to respond to urgent needs on Earth. So, Max, are you beginning to see the need for it?

Another perspective

Finally, I have to admit that I find it rather encouraging to see Russians, Americans, Japanese, Canadians and Europeans living together on the Space Station. Not so long ago, some of these countries were attacking each other with nuclear bombs. In space, no such borders exist.

Exploration brings people together. It opens our eyes to new perspectives. It shows us that we’re all in the same boat together. That’s pretty important, don’t you think, Max?

Our planet is magnificent and unique, an oasis of impossible life. But it is fragile. We need to protect it. That’s why exploring beyond the Earth should not be considered a luxury; it’s an investment in our shared humanity.

So, Max, when Jeremy Hansen and his crew take off in 2025, will you be there to watch them?

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This article is republished from The Conversation under a Creative Commons license. Read the original article.The Conversation

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Space exploration: A luxury or a necessity? (2024, April 16)
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