Earth's Hidden Mantle Secrets: Mars' Blue Past and the Cosmic Gas Pipeline of Galaxy Growth

Versus Spacetime Series twenty nine, Episode twelve, for broadcast on the twenty eighth of January twenty twenty six. Coming up on Space Time, Continents Deep inside the Earth's mantle, confirmation that the red planet Mars was once a blue planet, and a new studies discovered how galaxies can grow quickly by sucking in filaments of cool gas to feed growing stars. All that and more coming up on space Time. Welcome to space Time with Stuart Gary. Scientists studying the evolution of two massive, continent sized regions in the Earth's deep mantle have now discovered that each of their own very distinctive histories in chemical composition. The findings published in the journal Scientific Report, contradicts the previously held assumptions that they're both basically the same. Seismologists have long known that seismic waves generated by earthquakes do not travel through all parts of the Earth's interior at the same speed. Now it was this principle which allowed them to visualize the inside of our planet, even at depths inaccessible to humans, using techniques similar to those employed in CT scans for medical imaging deep inside the mantle. That's the almost three thousand kilometa thick layer between the Earth's molten iron outer core and its silica dominator crust. There are vast areas beneath the Pacific Ocean and under the African continent where seismic waves travel much slower than average. These large low velocity provinces are bigger than most continents, up to nine hundred kilometers in height thousands of kilometers wide. Now, one common hypothesis is that they're made up of oceanic crust that has pushed deep into the mantle at subduction zones. The crustal material was then stirred through the mantle opions of years and accumulated to form these large low velocity provinces. Researchers have typically assumed that both large low velocity provinces similar to each other in nature, with the same chemical composition and age. That's because the searsmic waves travel through both of them in similar ways. But now a new study has challenged this view by moddeling the formation of these large low velocity provinces through time. By combining a model of mantle convection, including how tectonic plates have moved over the Earth's surface over the last billion years, the study has been able to show that the African large low velocity Province consists of older and better mixed material than the Pacific large low velocity Province, which contains fifty percent more and much younger subducted oceanic crust, and is therefore more different to that of the surrounding mantle. The resulting differences in density could also explain why the African large low velocity Province is more diffuse and taller than its specific counterpart. The studies lead author, James Pattern from Cardiff University, says that because numerical simulations aren't perfect, he ran modible models for a range of parameters, and each time he found that the Pacific large low velocity Province was enriched in subducted oceanic crust, implying that Earth's recent subduction history is driving this difference. The models of this study also show that the Pacific large Low velocity Province is consistently being replenished with fresh oceanic crustal material for at least the last three hundred million years. That's because it's surrounded at the surface by a circle of subduction zones known as the Pacific Ring of Fire. Now by contrast, the African large low velocity province doesn't receive any new material at the same rate, and so the material is mixed more with its surrounding mantle, lowering its density. Until now, these differences have all been overlooked. That's because temperature is the dominant control on how fast seismic waves move through a material. But the models presented in this study demonstrate that both large low velocity provinces actually have the same temperature, which explains why they look seismically similar. The fact that these two large low velocity provinces differ in composition but not in temperature, is key to the story and explains why they appear to be the same seismically. Mind you, it's also fascinating to see the links between the movements of the plates on Earth's surface and structures three thousand kilometers deep in our planet. The high temperatures of the large low velocity provinces and their positioning in the deep mantle on each side of the planet means they also affect how heat is extracted from the Earth's core. This impacts convection in the outer core, a process that drives the planet's magnetic field, which in turn protects us and all life on the surface from the harmful effects of cosmic rays and solar activity. And when you think about it, it means that if the African and Pacific large low velocity provinces were different, heat may no longer be extracted symmetrically and that could lead to a magnetic field instability, not good news for any life on the planet's surface. This makes it important to understand the structure of the large low velocity provinces and how they influence hit extraction from the core. Scientists now need to account for this asymmetry in mantle density within their models of the deep Earth. This poses a challenge for observations, as the data that are being used often only provides information on symmetric structures within the Earth. They also need to look for data that can constrain the proposed date symmetry in density, for example by using observations of Earth's gravitational field. All in all, it's a fascinating look at how the Earth might have been so very different. This is space time still to come. Confirmation that the red planet Mars was once a blue planet, and a new studies discovered how galaxies can grow quickly by sucking in filaments of cool gas to feed growing stars. All that and more still to come on space time. A new study examining ancient Martian river deltas is providing further proof that the red planet was once a blue planet with a vast ocean. The findings, reported in the journal MPJ Space Exploration, are based on the detection of structures on Mars that are very similar to classic river deltas seen here on Earth. These are traces of rivers that have deposited their sediments into an ocean, and they showed that Mars was once a blue planet around three billion years ago. The existence of vast quantities of water on Mars has been a central topic in planetary research for years. Previous studies have already shown evidence of oceans and rivers on Mars, indicating a once humid and possibly wet habitable environment rather than the cold freeze dried desert. Mars is today the latest evidence of formal water and a possible river connection to an ocean with disco of it in The Vallas marineris the largest canyon system on the red planet, which stretches along the Martian Equator like a giant rip in the crust. The studies authors gain new insights in the geological history of Vallas Marineris. Using high resolution images from a number of spacecraft orbiting the red planet. They found geomorphological structures near the canyon system that resemble river deltas on Earth. The studies lead author, Ignatius Agadestria from the University of Burnet, Switzerland, says these unique high resolution satellite images have enabled scientists to study the Martian landscape in great detail by surveying and mapping. Scarp fronted deposits were discovered at the lower end of the canyon system, which are being interpreted as fan delta's fan delta's form, where a fan shaped cone of debris sediments grows after flowing directly into a standing body of water. The authors found that these structures matted on Mars are very similar to classic dotters on Earth were rivers to scorch into oceans. While not the first to postulate the existence and size of the ocean, those earlier claims were all based on less precise data and partly on indirect arguments. On the other hand, this new reconstruction of the sea level is based on clear evidence for such coastlines using the high resolution images. As a result, the authors were able to provide clear evidence of the deepest and largest former ocean on Mars to date, an ocean that stretched right across the planet's northern hemisphere. Now today wind sculptor dunes cover the former delta structures, however their original shape is still clearly recognizable. The authors say the discovery of deltas and the confirmation of evidence of a former ocean suggests that conditions once prevailed on the red planet that could have favored the emergence and development of life as we know it. This is space time still to come. A new studies discovered how galaxies can grow quickly by sucking in filaments of cool gas to feed growing stars, and later in the science report, discovery of the oldest known rockeart in the world, dating back some sixty seven thousand years. All that and more still to come on space time. This episode of space Time is brought to you by squarespace, the platform that makes building an incredible online presence not just possible but effortless. Squarespace gives you all the tools you need to create a professional website, claim your perfect domain, promote your brand, and even get paid, all in one easy to use place. And here's where it gets really exciting. Squarespace's design tools give everyone the power to create a website that looks like it came from a top tier design studio. Start with blueprint a one which asks a few simple questions about your business and goals, and then generates a custom site complete with design suggestions and content ideas. Or you can choose from their award winning templates and then easily tweak them with intuitive dragon and drop editing, dynamic visual effects, and flexible styling options. The result is a website that is unmistakably yours. No coding or design degree required. Now, if you want to see how easy it is to bring your ideas to life online, visit squarespace dot com slash space time for a free trial, and when you're ready to launch, use the code space time at the checkout. Save ten percent on your first purchase for a website of domain. That's square space dot com slash space time promo code space time and of course we have a link in our show notes. You're listening to space Time and space Time with Steward Garry. A new study is discovered how galaxies can grow quickly by sacking in filaments of cool gas to feed growing stars. Apart from merging with other galaxies, individual galaxies grow by accumulating gas and dust from their surroundings and then converting that into stars, but the details of this process remained somewhat murky. However, observations reported in the journal Nature Astronomy made using the Kick telescope's cosmic web image are provided clear direct evidence that filaments of cool gas were spiraling into young galaxies, supplying the fuel for star formation. The studies lead author, Christopher Mant from cal Tech, says that these were the first observations showing filaments of gas directly spiraling into a galaxy. He describes it as being like a pipeline going straight in, sustaining star formation and explaining how galaxies can make stars on very fast timescales. For years now, astronomers have been debating exactly how gas makes its way to the center of galaxies. Does it heat up dramatically as it collides with the surrounding hot gas, or does it simply stream in along dense filaments, remaining relatively cold. Modern theory suggests the answer is probably a mix of birth, but proving the existence of these cold streams of gas has remained a major challenge until now. After their initial observations on the Cosmic Web imager, the authors then used an integral field unit spectrograph also attached to the Keck telescope, in order to take more high resolution images in which every pixel on the image contains its own disperse spectrum of light. In fact, this amazing instrument as some eight times the spatial resolution and ten times the sensitivity of the Cosmic Web imager. The question of how galaxies had stars form out of a network of wispy filaments in space known as the cosmic web as long fascinated astronomers. To find the answers, Martin and colleagues acquired data from two active galaxies known as quasars, cataloged as UM two eighty seven and CSO thirty eight. But it wasn't the quasars themselves that the astronomers wanted to study. You see, nearby each of these two quasars was a giant nebula, larger than the Milky Way and clearly visible to the astronomers thanks to the strong illumination of the quasars themselves by looking at light emitted by hydrogen in the nebulosity is specifically an atomic emission line known as the hydrogen Linemen alpha. They were able to map the velocity of the gas now from previous observations at the Palomar Observatory in California. The authors already knew that there were signs of rotation within the nebulosities, but the KECT data revealed far more. Palima allowed them to see what looked like a rotating disk of gas, but they couldn't make out any filaments. However, the new KEC data allowed the astronomers to devote more sophisticated models and see that these objects are being fed by gas flowing in from attached filaments, which is strong evidence that the cosmic web is connected to and fueling this disk. Martin and colleagues developed a mathematical model to explain the velocities they were seeing in the gas, and they then tested that on U two eighty seven and COSO thirty eight, as well as on a computer simulated galaxy, and the findings are providing the best evidence yet for the cold flow model of galaxy formation, which basically states that cold gas can flow directly into a forming gas galaxy where it's then converted into stars. Before this model came into popularity, research as Head proposed, the galaxy is pulling gas and then heated it too extremely high temperatures. From there, the gas was thought to gradually cool down again, providing a steady but slow supply of fuel for star formation. But in nineteen ninety six, researchers through that model into question after it was shown that distant galaxies produce stars at very high rates, too fast to be a catidph by the slow settling and cooling of hot gas. That was a favorite model for young galaxy fueling. One of the studies authors, Donald O'Sullivan, says, the new findings provide the answer by showing how filaments of cold gas can stream into a galaxy, providing the fuel needed for star formation. When you look at the sky, you see billions and billions of galaxies, and I think a very natural question to ask is how do they get there? Why do they have the kind of shapes and sizes and colors that they do. And in order to be able to answer that question, you need to understand the environment they came from, the environment that they're growing with, and that is the cosmic web. The cosmic web is the gas between galaxies, the intergalactic medium, and we nickname it the cosmic web because it's spread out in what looks kind of like a spider web filamentary structure. What we are trying to do is make maps of the cosmic web. With Palomar, we looked at this gas. You see what looks like a disc, and you see that it's rotating. But our resolution was not great, but just enough to be able to say, we think that this is a giant disc of gas ten times the size of the Milky Way, and we think it's rotating. With case WI, because of the increased sensitivity and the increased resolution, we were able to provide very strong evidence that we are directly observing filaments of gas connecting to this disc from the cosmic web. And look at how they changed its velocities and how they changed its morphology. And this has been predicted in theory and simulations but never yet observed. Working on instrumentation at Caltech, it's incredible because you're building new ways of looking at the universe which maybe weren't accessible before. I've built a small part of key cosmic web imager. Working with Chris Martin, you really get trusted with serious responsibilities to build important things. We want to achieve two things with the Cosmic Web Imager. We want to be able to look at spectroscopy, meaning the color of the light. We also want to get a full two D image. Hydrogen emits at very specific colors. Helium emits a very specific colors, So the way we identify gas is by atomic emission. So you get an image where at every pixel you also get a spectrum of light. In every pixel, you say, is there hydrogen here, and you can make a map of that gas. One thing I'm really looking forward to with the ke Cosmic Web Imager is that we're going to be able to collect a large sample of observations like this. Where one or two case studies is nice, what's really great is to be able to look at tens or hundreds of objects and build up a big picture of how these processes work in the early universe and how galaxies form and evolve in a more statistical sense. That's Donald O'Sullivan from cow Tech and this is Space Time and Time that attack. Another brief look at some of the other stories making news and science. This week with the Science report, anthropologists have discovered the oldest known rockeute in the world, dating back some sixty seven thousand years in a cave on the Indonesian island of Sulawesi. The new findings, reported in the journal Nature, are some eleven hundred years older than the previous record setter and fifteen thousand years older than cave out previously found by the same team in the same region. The authors say the findings advanced sciences understanding of how and when Australia first came to be settled, with a Siloweesi art very likely created by a population closely linked to the ancestors of indigenous Australians. A new study suggested the power of the ancient theThe Sea may have shaped Central Asia's topography during the Cretaceous period. The findings, reported in the journal Communications Earth and Environment, based on a big data approach that involved hundreds of thermal history models for Central Asia throughout three decades of research. The Tethe Sea was a vast prehistoric ocean that separated the supercontinents of Gone Wander and Larasia from the late Palaeozoic through to the Sinozoic eras acting as a major maritime highway for life before its closure formed today's Indian Ocean, Mediterranean Sea, and Eurasian inland seas. It was characterized by warm tropical conditions that fostered abundant marine life, including reef ecosystems, and significantly influenced global climate and ocean currents of the time. Oh Now, brown cow has taken a whole new meaning with behavioral tests of a pet cow showing for the first time that cattle are capable of versatile tool use. A report in the journal Current Biology has shown how a bovine named Veronica could use a broom to scratch herself. The authors showed that she would pick up the broom and use the brush end to scratch areas like her back with forceful movements, and then she could turn the broom around and use the stick handle end more carefully for those sensitive areas like her adder. The authors say this is the first experimental verification of tools being used by a cow, but this capacity may well be more widespread, though unlike Veronica, cows and impoverished farm environments may not get the opportunity to show it. In fact, the finding show that livestock intelligence may have been severely underestimated due to gaps in our observation. Well, it's taken a long long time, but Apple are finally planning to overhaul their Aging Intelligent Virtual Assistance SIRI, transforming it into a chatbot similar to x as grock, Open AI's chat GPT and Google's Gemini. With the details with a job by technology editor Alex saharav Ry from Tech Advice start Live. Well, for the longest time, Apple has said that it wasn't interested in having a series GPT where it was a chatbot in the style of Chat JVT or Gemini. I mean, anybody can download those now and they can see what a great job those particular programs do. But in the last few weeks we've had confirmation that Apple is going to have a white label version of Gemini, and they're going to supposedly still be running on Google service, but running under its own private cloud compute infrastructure, so Google won't have access to what's being searched, what's being asked about, and Apple will maintain its privacy. Now, coming in March or April is meant to be iOS twenty six point four, which will have the beginnings of this more intelligent Sery won't have the chatbot yet. That's supposed to be coming in iOS twenty seven and previewed the Worldwide Developer Conference in the middle year, when Apple normally showcases what's coming next, but it is well over a year late. With its version of Siri that can look at the apps that you're using, fish out information on who you met at the cafe two or three weeks ago when you were there, from SMS, messages, from emails, from calendar appointments, and Apple will have access to its apps in a much deeper way than chat, GPT or Gemini themselves can have because Apple's just not giving that sort of access to outside apps. And so, look, this has only just come out in the last day or so with Mark German from Bloomberg, the unofficial spokesperson for Apple, he leaks all this information. He's obviously getting it from Apple, but clearly it's one of those things where they leak it to him and then everyone else talks about it, and that's how Apple gets a lot of its messages out without having an official launch. And there's also been news as well that Apple is working on an air tag sized AI wearable with some cameras. Now, if you have seen the Humane pin that had that sort of capability that failed a year or two ago, was beaming information into your hand via a laser, but it just didn't work pretty well. When I was at ces Murderole, a part of Lenovo, they also had a wearable necklace type of pin that you could listen to everything and had a camera so I would record things. And you know then like these AI devices, they can memorize everything. It can give you notes, give you a transcript, tell you what you agreed to do, what the next steps are. And in other companies are working on this as well. We've got open Ai with Johnny I, the former Apple chief designer, working with Sam Oltman from open Ai to create some sort of an AI pin as well that is a screenless device. So there's a lot of people working on this. I mean, you can certainly imagine that someone like Apple was going to have the wherewithal to create this and stick by it and make sure that it really does respect privacy. And Apple has been missing in this space. They have done a lot of things to try and make theory better, but series the worst of all of the AI systems at the moment, but you know, I'm very hopeful that in April will have twenty two point four and you'll be much better. And then from about June July this year when they have WWDC, I mean it'll be first to put it on one of my phones to test out this new serie GPT chat pot and hopefully it's as good as we would expect it to be. That's Alexaharavroyd from Techadvice dot Live. And this is Spacetime and that's the show for now. Space Time is available every Monday, Wednesday and Friday through fites dot com, SoundCloud, YouTube, your favorite podcast download provider, and from space Time with Stuart Gary dot com. Space Time's also broadcast through the National Science Foundation, on Science Own Radio and on both iHeartRadio and tune in Radio. And you can help to support our show by visiting the space Time Store for a range of promotional merchandising goodies, or by becoming a Spacetime Patron, which gives you access to triple episode commercial free versions of the show, as well as lots of burnus audio content which doesn't go to weir, access to our exclusive Facebook group, and other rewards. Just go to space Time with Stewart Gary dot com For full details. You've been listening to Space Time with Stuart Gary. This has been another quality podcast production from bytes dot com.