Category: 7. Science

  • See a rare dinosaur or a chunk of Mars during Sotheby’s ‘Geek Week’

    See a rare dinosaur or a chunk of Mars during Sotheby’s ‘Geek Week’

    New Yorkers may not think of Sotheby’s, the tony auction house on the Upper East Side, as a place to casually pop in to, let alone a place to see dinosaurs or Martian meteorites.

    But during “Geek Week,” that’s exactly what’s on free public view. From July 8 to 15, Sotheby’s is displaying some remarkable objects of natural history, science and space exploration before they hit the auction block.

    This year’s standout is a six-foot-tall, 10-foot-long juvenile Ceratosaurus, one of only four known specimens of this extremely rare Jurassic dinosaur.

    The roughly 150 million-year-old fossil, which has been reconstructed with a few ceramic elements to replace missing pieces, was discovered in Wyoming in 1996, according to Cassandra Hatton, Sotheby’s vice chairman of science and natural history.

    It’s expected to sell for between 4 and 6 million dollars.

    The sale includes more than 100 ancient items, sourced from various collectors, including dinosaur skulls and claws, chunks of meteorites, a 4,000-year-old stone axe and astonishing, iridescent slices of mineral and crystal, all on view.

    Another showstopper is a 54-pound Martian meteorite – the largest known piece of Mars on Earth. This chunk of the Red Planet is believed to have been chipped off by one of only 16 known asteroid strikes powerful enough to launch debris into space, before landing in the Sahara desert.

    “That chunk had to be loose enough to break off, and then it had to get on the right trajectory to travel 140 million miles to Earth, and then it had to land in a spot where someone could find it,” Hatton said. “And then we were lucky enough that someone came by who knew enough about meteorites to recognize that it wasn’t just a big rock.”

    Hatton said scientists were able to confirm the meteorite’s extraterrestrial origin by extracting gas trapped in bubbles inside the rock and comparing it to Martian atmospheric data transmitted from NASA’s Viking lander in 1976.

    The sale also includes objects that went to space with astronaut Buzz Aldrin, from his collection.

    Another highlight includes what Hatton describes as the finest operational Apple-1 computer in existence: one of 50 machines hand-built by Steve Wozniak and Steve Jobs in 1976.

    The Apple founders had built a few prototypes and were shopping them around town, Hatton said, when a local shopkeeper happened to see their presentation at the Home Brew Computer Club, an early computer hobbyist group in Menlo Park, California. He asked for 50, which sent the techies scrambling for parts to fulfill a bigger order than they’d anticipated.

    The sale also includes one of Jobs’ earliest business cards, expected to sell for $5,000 to 8,000.

    For those who associate Sotheby’s with high-stakes blue-chip art sales and exclusivity, Geek Week is a reminder that the auction house doubles as a pop-up museum.

    Hatton said she’s the only science specialist on staff.

    “I go from scientific books and manuscripts to tech, dinosaurs, minerals, meteorites, space exploration,” Hatton said. “I do hip-hop sales sometimes too. It all connects together somehow, in my mind.”

    Sotheby’s Geek Week is at 1334 York Ave. from July 8 through 15, open from 10 a.m. to 5 p.m. every day except Sunday, when it opens at 1 p.m. No RSVP is required.

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  • NASA’s Hubble and Webb Telescopes Reveal Two Faces of a Star Cluster Duo

    NASA’s Hubble and Webb Telescopes Reveal Two Faces of a Star Cluster Duo

    A riotous expanse of gas, dust, and stars stake out the dazzling territory of a duo of star clusters in this combined image from NASA’s Hubble and Webb space telescopes.

    Open clusters NGC 460 and NGC 456 reside in the Small Magellanic Cloud, a dwarf galaxy orbiting the Milky Way. Open clusters consist of anywhere from a few dozen to a few thousand young stars loosely bound together by gravity. These particular clusters are part of an extensive complex of star clusters and nebulae that are likely linked to one another. As clouds of gas collapse, stars are born. These young, hot stars expel intense stellar winds that shape the nebulae around them, carving out the clouds and triggering other collapses, which in turn give rise to more stars.

    In these images, Hubble’s view captures the glowing, ionized gas as stellar radiation blows “bubbles” in the clouds of gas and dust (blue), while Webb’s infrared vision highlights the clumps and delicate filamentary structures of dust (red). In Hubble images, dust is often seen silhouetted against and blocking light, but in Webb’s view, the dust – warmed by starlight – shines with its own infrared glow. This mixture of gas and dust between the universe’s stars is known as the interstellar medium.

    The nodules visible in these images are scenes of active star formation, with stars ranging from just one to 10 million years old. In contrast, our Sun is 4.5 billion years old. The region that holds these clusters, known as the N83-84-85 complex, is home to multiple, rare O-type stars, hot and extremely massive stars that burn hydrogen like our Sun. Astronomers estimate there are only around 20,000 O-type stars among the approximately 400 billion stars in the Milky Way.

    The Small Magellanic Cloud is of great interest to researchers because it is less enriched in metals than the Milky Way. Astronomers call all elements heavier than hydrogen and helium – that is, with more than two protons in the atom’s nucleus – “metals.”  This state mimics conditions in the early universe, so the Small Magellanic Cloud provides a relatively nearby laboratory to explore theories about star formation and the interstellar medium at early stages of cosmic history. With these observations of NGC 460 and NGC 456, researchers intend to study how gas flows in the region converge or divide; refine the collision history between the Small Magellanic Cloud and its fellow dwarf galaxy, the Large Magellanic Cloud; examine how bursts of star formation occur in such gravitational interactions between galaxies; and better understand the interstellar medium.

    Explore More

    Media Contact:

    Claire Andreoli
    NASA’s Goddard Space Flight CenterGreenbelt, MD
    claire.andreoli@nasa.gov

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  • Scientists Discover Giant Sand Bodies Beneath The North

    Scientists Discover Giant Sand Bodies Beneath The North

    Scientists have discovered hundreds of giant sand bodies beneath the North Sea that appear to defy fundamental geological principles and could have important implications for energy and carbon storage.

    Using high-resolution 3D seismic (sound wave) imaging, combined with data and rock samples from hundreds of wells, researchers from The University of Manchester in collaboration with industry, identified vast mounds of sand—some several kilometers wide—that appear to have sunk downward, displacing older, lighter and softer materials from beneath them.

    The result is stratigraphic inversion—a reversal of the usual geological order in which younger rocks are typically deposited on top of older ones—on a previously unseen scale.

    While stratigraphic inversion has previously been observed at small scales, the structures discovered by the Manchester team, now named “sinkites,” are the largest example of the phenomenon documented so far.

    The finding, published in the journal Communications Earth & Environment, challenges scientists understanding of the subsurface and could have implications for carbon storage.

    “This discovery reveals a geological process we haven’t seen before on this scale,” said lead author Professor Mads Huuse from The University of Manchester. “What we’ve found are structures where dense sand has sunk into lighter sediments that floated to the top of the sand, effectively flipping the conventional layers we’d expect to see and creating huge mounds beneath the sea.”

    It is believed the sinkites formed millions of years ago during the Late Miocene to Pliocene periods, when earthquakes or sudden shifts in underground pressure may have caused the sand to liquefy and sink downward through natural fractures in the seabed. This displaced the underlying, more porous but rigid, ooze rafts—composed largely of microscopic marine fossils—bound by shrinkage cracks, sending them floating upwards. The researchers have dubbed these lighter, uplifted features “floatites.”

    The finding could help scientists better predict where oil and gas might be trapped and where it’s safe to store carbon dioxide underground.

    “This research shows how fluids and sediments can move around in the Earth’s crust in unexpected ways. Understanding how these sinkites formed could significantly change how we assess underground reservoirs, sealing, and fluid migration—all of which are vital for carbon capture and storage,” said Huuse. 

    Now the team are busy documenting other examples of this process and assessing how exactly it impacts our understanding of subsurface reservoirs and sealing intervals.

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  • Volcano Ice Unlocks Age of Milky Ways Core Gas’

    Volcano Ice Unlocks Age of Milky Ways Core Gas’

    Researchers have found clouds of cold gas embedded deep within larger, superheated gas clouds – or Fermi bubbles – at the Milky Way’s center. The finding challenges current models of Fermi bubble formation and reveals that the bubbles are much younger than previously estimated.

    “The Fermi bubbles are enormous structures of hot gas that extend above and below the disk of the Milky Way, reaching about 25,000 light years in each direction from the galaxy’s center – spanning a total height of 50,000 light years,” says Rongmon Bordoloi, associate professor of physics at North Carolina State University and corresponding author of the research.

    “Fermi bubbles are a relatively recent discovery – they were first identified by telescopes that ‘see’ gamma rays in 2010 – there are different theories about how it happened, but we do know that it was an extremely sudden and violent event, like a volcanic eruption but on a massive scale.”

    Bordoloi and the research team used the U.S. National Science Foundation Green Bank Telescope (NSF GBT) to observe the Fermi bubbles and get high resolution data about the composition of the gas within and the speed at which it is moving. These measurements were twice as sensitive as previous radio telescope surveys of the Fermi bubbles and allowed them to observe finer detail within the bubbles.

    Most of the gas inside the Fermi bubbles is around 1 million degrees Kelvin. However, the research team also found something surprising: dense clouds of neutral hydrogen gas, each one measuring several thousand solar masses, dotted within the bubbles 12,000 light years above the center of the Milky Way.

    “These clouds of neutral hydrogen are cold, relative to the rest of the Fermi bubble,” says Andrew Fox, ESA-AURA Astronomer at the Space Telescope Science Institute and coauthor of the paper.

    “They’re around 10,000 degrees Kelvin, so cooler than their surroundings by at least a factor of 100. Finding those clouds within the Fermi bubble is like finding ice cubes in a volcano.”

    Their existence is surprising because the hot (over 1 million degrees Kelvin), high-velocity environment of the nuclear outflow should have rapidly destroyed any cooler gas.

    “Computer models of cool gas interacting with hot outflowing gas in extreme environments like the Fermi bubbles show that cool clouds should be rapidly destroyed, usually within a few million years, a timescale that aligns with independent estimates of the Fermi bubbles’ age,” Bordoloi says. “It wouldn’t be possible for the clouds to be present at all if the Fermi bubbles were 10 million years old or older.

    “What makes this discovery even more remarkable is its synergy with ultraviolet observations from the Hubble Space Telescope (HST),” Bordoloi says. “The clouds lie along a sightline previously observed with HST, which detected highly ionized multiphase gas, ranging in temperatures from a million to 100,000 Kelvin – which is what you’d expect to see if a cold gas is getting evaporated.”

    The team was also able to calculate the speed at which the gases are moving, which further confirmed the age.

    “These gases are moving around a million miles per hour, which also marks the Fermi bubbles as a recent development,” Bordoloi says. “These clouds weren’t here when dinosaurs roamed Earth. In cosmic time scales, a million years is the blink of an eye.”

    “We believe that these cold clouds were swept up from the Milky Way’s center and carried aloft by the very hot wind that formed the Fermi bubbles,” says Jay Lockman, an astronomer at the Green Bank Observatory and coauthor of the paper. “Just as you can’t see the motion of the wind on Earth unless there are clouds to track it, we can’t see the hot wind from the Milky Way but can detect radio emission from the cold clouds it carries along.”

    This discovery challenges current understanding of how cold clouds can survive the extreme energetic environment of the Galactic Center, placing strong empirical constraints on how outflows interact with their surroundings. The findings provide a crucial benchmark for simulations of galactic feedback and evolution, reshaping our view of how energy and matter cycle through galaxies.

    The work appears in Astrophysical Journal Letters and is supported by the National Science Foundation under grant number AST-2206853.

    -peake-

    /Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.

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  • Vortex Particle Method Boosts High Reynolds Flow Simulations

    The Vortex Particle Method (VPM), a meshless vortex flow simulation approach, is gaining traction for its efficient simulation of unsteady vortex wakes evolution that is shed by aircrafts, rotors and wind turbines. It outperforms traditional grid-based CFD methods with faster computation, lower dissipation, and easier satisfaction of the CFL stability condition. However, traditional VPM has huge challenge on accurately simulating these complex flows, due to its poor numerical stability, which is compromised by factors such as Lagrangian particle distortion, vorticity field divergence, and inadequate modeling of turbulent dissipation. These issues restrict its application in high Reynolds number and high velocity gradient flows.

    Recently, a team of aviation researchers led by Min Chang from Northwestern Polytechnical University in China have developed a Stability-enhanced VPM (SEVPM) based on a Reformulated VPM (RVPM) constrained by conservation of angular momentum. SEVPM integrated a relaxation scheme to suppress the divergence of the vorticity field and coupled a Sub-Grid Scale (SGS) model to account for turbulence dissipation caused by vortex advection and vortex stretching. These advancements enable stable, high-fidelity simulations of complex flows that were previously computationally prohibitive.

    The team published their work in the Chinese Journal of Aeronautics (Vol. 38, Issue 7, 2025).

    The new SEVPM addresses these issues by incorporating a Reformulated VPM (RVPM) that enforces angular momentum conservation, a relaxation scheme to maintain a divergence-free vorticity field, and a novel Sub-Grid Scale (SGS) model that accounts for turbulence dissipation from both vortex advection and stretching. These advancements enable VPM more stable and precise simulations of complex fluid dynamics, providing engineers and researchers with a more reliable tool for predicting fluid behavior of vortex flow in practical applications.

    The researchers demonstrated that their SEVPM can accurately and stably simulate high Reynolds number flows and shear turbulence. Through a series of validation cases, including isolated vortex ring evolution, leapfrogging vortex rings, and round turbulent jet simulations, they showed that the new method significantly improves numerical stability and accurately resolves fluctuating components and Reynolds stresses in turbulence. This advancement paves the way for more reliable and efficient computational simulations in fluid dynamics, which is essential for understanding and predicting complex flow phenomena in engineering applications. “Engineers hit a wall simulating shear turbulence like jet exhausts or rotor interactions with traditional VPM. Our work tears down that wall,” says lead author Xiaoxuan Meng.

    The researchers plan to further validate and refine the Stability-enhanced VPM by applying it to more complex and realistic flow scenarios. Future work includes simulating the aerodynamic interactions of multirotor systems, wake dynamics of wind turbines, and other practical applications in aeronautics and renewable energy. The ultimate goal is to establish the Stability-enhanced VPM as a robust computational tool for high-fidelity fluid flow simulations, enabling more accurate predictions and driving innovation in design and optimization of aerospace and energy systems. “Our ultimate goal is making high-fidelity turbulence simulation as routine as structural analysis,” says Min Chang. “This unlocks smarter, greener aviation and energy systems.”

    Original Source

    Xiaoxuan Meng, Junqiang Bai, Ziyi Xu, Min Chang, Zhe Hui. Stability-enhanced viscous vortex particle method in high Reynolds number flow and shear turbulence[J]. Chinese Journal of Aeronautics, 2025, 38(7): 103361, https://doi.org/10.1016/j.cja.2024.103361 .

    About Chinese Journal of Aeronautics

    Chinese Journal of Aeronautics (CJA) is an open access, peer-reviewed international journal covering all aspects of aerospace engineering, monthly published by Elsevier. The Journal reports the scientific and technological achievements and frontiers in aeronautic engineering and astronautic engineering, in both theory and practice. CJA is indexed in SCI (IF = 5.7, Q1), EI, IAA, AJ, CSA, Scopus.

    /Public Release. This material from the originating organization/author(s) might be of the point-in-time nature, and edited for clarity, style and length. Mirage.News does not take institutional positions or sides, and all views, positions, and conclusions expressed herein are solely those of the author(s).View in full here.

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  • Australia researchers make ammonia from air and electricity | Ammonia

    Australia researchers make ammonia from air and electricity | Ammonia

    University of Sydney researchers have harnessed human-made lightning to develop a more efficient method of generating ammonia.

    The current method to generate ammonia, the Haber-Bosch process, comes at great climate cost, leaving a huge carbon footprint. It also needs to happen on a large scale and close to sources of cheap natural gas to make it cost effective.

    Lead researcher Professor PJ Cullen from the University of Sydney’s School of Chemical and Biomolecular Engineering and the Net Zero Institute, said industry’s appetite for ammonia is only growing.

    “For the past decade, the global scientific community, including our lab, wants to uncover a more sustainable way to produce ammonia that doesn’t rely on fossil fuels,” he said.

    “Currently, generating ammonia requires centralised production and long-distance transportation of the product. We need a low-cost, decentralised and scalable green ammonia.”

    The research is the culmination of six years’ work.

    “In this research we’ve successfully developed a method that allows air to be converted to ammonia in its gaseous form using electricity,” he said.

    Professor Cullen’s team’s new method to generate ammonia works by harnessing the power of plasma, by electrifying or exciting the air.

    But the star is a membrane-based electrolyser, a seemingly non-descript silver box, where the conversion to gaseous ammonia happens.

    During the Haber-Bosch process, ammonia is made by combining nitrogen and hydrogen gases under high temperatures and pressure in the presence of catalyst.

    The plasma-based method Professor Cullen’s team developed uses electricity to excite nitrogen and oxygen molecules in the air. The team then passes these molecules to the membrane-based electrolyser to convert them to ammonia.

    Professor Cullen said the findings signal a new phase in making green ammonia possible and his team is now working on making the method more energy efficient and competitive compared to the Haber-Bosch process.

    “This new approach is a two-step process, namely combining plasma and electrolysis. We have already made the plasma component viable in terms of energy efficiency and scalability,” he said.

    “To create a more complete solution to a sustainable ammonia productive, we need to push the energy efficiency of the electrolyser component.”

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  • Earth is going to spin much faster over the next few months — so fast that several days are going to get shorter

    Earth is going to spin much faster over the next few months — so fast that several days are going to get shorter

    Earth is expected to spin more quickly in the coming weeks, making some of our days unusually short. On July 9, July 22 and Aug. 5, the position of the moon is expected to affect Earth’s rotation so that each day is between 1.3 and 1.51 milliseconds shorter than normal.

    A day on Earth is the length of time needed for our planet to fully rotate on its axis — approximately 86,400 seconds, or 24 hours. But Earth’s rotation is affected by a number of things, including the positions of the sun and moon, changes to Earth’s magnetic field, and the balance of mass on the planet.

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  • See asteroid Donaldjohanson up close thanks to NASA’s Lucy mission photo of the day for July 7, 2025

    See asteroid Donaldjohanson up close thanks to NASA’s Lucy mission photo of the day for July 7, 2025

    NASA’s Lucy mission is key to helping us understand the early history of our solar system as it studies asteroids like the Donaldjohanson.

    What is it?

    Named after the paleoanthropologist who co-discovered the Lucy skeleton, NASA’s Lucy space probe is key to helping scientists understand the early history of our solar system. Launched on Oct. 16, 2021, Lucy is the first space mission designed specifically to study Trojan asteroids, which are ancient remnants from the early solar system that share orbits with the sun and Jupiter.

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  • See asteroid Donaldjohanson up close thanks to NASA’s Lucy mission photo of the day for July 7, 2025

    See asteroid Donaldjohanson up close thanks to NASA’s Lucy mission photo of the day for July 7, 2025

    NASA’s Lucy mission is key to helping us understand the early history of our solar system as it studies asteroids like the Donaldjohanson.

    What is it?

    Named after the paleoanthropologist who co-discovered the Lucy skeleton, NASA’s Lucy space probe is key to helping scientists understand the early history of our solar system. Launched on Oct. 16, 2021, Lucy is the first space mission designed specifically to study Trojan asteroids, which are ancient remnants from the early solar system that share orbits with the sun and Jupiter.

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  • ‘Ice in a Volcano’ Reveals Age of Gas Cloud at Milky Way’s Center

    ‘Ice in a Volcano’ Reveals Age of Gas Cloud at Milky Way’s Center

    Researchers have found clouds of cold gas embedded deep within larger, superheated gas clouds – or Fermi bubbles – at the Milky Way’s center. The finding challenges current models of Fermi bubble formation and reveals that the bubbles are much younger than previously estimated.

    “The Fermi bubbles are enormous structures of hot gas that extend above and below the disk of the Milky Way, reaching about 25,000 light years in each direction from the galaxy’s center – spanning a total height of 50,000 light years,” says Rongmon Bordoloi, associate professor of physics at North Carolina State University and corresponding author of the research.

    “Fermi bubbles are a relatively recent discovery – they were first identified by telescopes that ‘see’ gamma rays in 2010 – there are different theories about how it happened, but we do know that it was an extremely sudden and violent event, like a volcanic eruption but on a massive scale.”

    Bordoloi and the research team used the U.S. National Science Foundation Green Bank Telescope (NSF GBT) to observe the Fermi bubbles and get high resolution data about the composition of the gas within and the speed at which it is moving. These measurements were twice as sensitive as previous radio telescope surveys of the Fermi bubbles and allowed them to observe finer detail within the bubbles.

    Most of the gas inside the Fermi bubbles is around 1 million degrees Kelvin. However, the research team also found something surprising: dense clouds of neutral hydrogen gas, each one measuring several thousand solar masses, dotted within the bubbles 12,000 light years above the center of the Milky Way.

    “These clouds of neutral hydrogen are cold, relative to the rest of the Fermi bubble,” says Andrew Fox, ESA-AURA Astronomer at the Space Telescope Science Institute and coauthor of the paper.

    “They’re around 10,000 degrees Kelvin, so cooler than their surroundings by at least a factor of 100. Finding those clouds within the Fermi bubble is like finding ice cubes in a volcano.”

    Their existence is surprising because the hot (over 1 million degrees Kelvin), high-velocity environment of the nuclear outflow should have rapidly destroyed any cooler gas.

    “Computer models of cool gas interacting with hot outflowing gas in extreme environments like the Fermi bubbles show that cool clouds should be rapidly destroyed, usually within a few million years, a timescale that aligns with independent estimates of the Fermi bubbles’ age,” Bordoloi says. “It wouldn’t be possible for the clouds to be present at all if the Fermi bubbles were 10 million years old or older.

    “What makes this discovery even more remarkable is its synergy with ultraviolet observations from the Hubble Space Telescope (HST),” Bordoloi says. “The clouds lie along a sightline previously observed with HST, which detected highly ionized multiphase gas, ranging in temperatures from a million to 100,000 Kelvin – which is what you’d expect to see if a cold gas is getting evaporated.”

    The team was also able to calculate the speed at which the gases are moving, which further confirmed the age.

    “These gases are moving around a million miles per hour, which also marks the Fermi bubbles as a recent development,” Bordoloi says. “These clouds weren’t here when dinosaurs roamed Earth. In cosmic time scales, a million years is the blink of an eye.”

    “We believe that these cold clouds were swept up from the Milky Way’s center and carried aloft by the very hot wind that formed the Fermi bubbles,” says Jay Lockman, an astronomer at the Green Bank Observatory and coauthor of the paper. “Just as you can’t see the motion of the wind on Earth unless there are clouds to track it, we can’t see the hot wind from the Milky Way but can detect radio emission from the cold clouds it carries along.”

    This discovery challenges current understanding of how cold clouds can survive the extreme energetic environment of the Galactic Center, placing strong empirical constraints on how outflows interact with their surroundings. The findings provide a crucial benchmark for simulations of galactic feedback and evolution, reshaping our view of how energy and matter cycle through galaxies.

    The work appears in Astrophysical Journal Letters and is supported by the National Science Foundation under grant number AST-2206853.

    -peake-

    Note to editors: An abstract follows.

    “A New High-latitude H I Cloud Complex Entrained in the Northern Fermi Bubble”

    DOI: 10.3847/2041-8213/addd16

    Authors: Rongmon Bordoloi, North Carolina State University; Andrew Fox, Space Telescope Science Institute; Felix Lockman, Green Bank Observatory
    Published: July 7 in Astrophysical Journal Letters

    Abstract:
    We report the discovery of eleven high-velocity H I clouds at Galactic latitudes of 25–30 degrees, likely embedded in the Milky Way’s nuclear wind. The clouds are detected with deep Green Bank Telescope 21 cm observations of a 3.2◦×6.2◦ field around QSO 1H1613-097, located behind the northern Fermi Bubble. Our measurements reach 3σ limits on NHI as low as 3.1 × 1017 cm−2, more than twice as sensitive as previous H I studies of the Bubbles. The clouds span −180 ≤ vLSR ≤ −90 kms−1 and are the highest-latitude 21 cm HVCs detected inside the Bubbles. Eight clouds are spatially resolved, showing coherent structures with sizes of 4–28 pc, peak column densities of log(NHI/cm2)=17.9–18.7, and H I masses up to 1470M⊙. Several exhibit internal velocity gradients. Their presence at such high latitudes is surprising, given the short expected survival times for clouds expelled from the Galactic Center. These objects may be fragments of a larger cloud disrupted by interaction with the surrounding hot gas.


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