Category: 7. Science

  • Sea levels are rising as predicted – with bigger risks ahead

    Sea levels are rising as predicted – with bigger risks ahead

    For centuries, humanity relied on coastal landmarks and tide gauges to understand sea levels. But satellites changed everything. Since the early 1990s, orbiting instruments have provided precise, global records of ocean surface height.

    These data revealed not only how seas are rising but also how predictions from decades ago were impressively accurate.

    Satellites changed sea-level tracking


    Study lead author Torbjörn Törnqvist is a professor in the Department of Earth and Environmental Sciences at Tulane University.

    “The ultimate test of climate projections is to compare them with what has played out since they were made, but this requires patience – it takes decades of observations,” said Törnqvist.

    He noted that the team was quite amazed at how good those early projections were, especially considering how crude the models were back then, compared to what is available now.

    “For anyone who questions the role of humans in changing our climate, here is some of the best proof that we have understood for decades what is really happening, and that we can make credible projections.”

    Sea-level rise differs across regions

    Professor Sönke Dangendorf emphasized the importance of translating global patterns into regional forecasts.

    “Sea level doesn’t rise uniformly – it varies widely. Our recent study of this regional variability and the processes behind it relies heavily on data from NASA’s satellite missions and NOAA’s ocean monitoring programs,” he said.

    “Continuing these efforts is more important than ever, and essential for informed decision-making to benefit the people living along the coast.”

    Satellites confirm acceleration

    When satellites first began tracking sea levels in the early 1990s, they showed an average increase of about one eighth of an inch per year. It was only later that scientists confirmed this pace was speeding up.

    By October 2024, NASA researchers announced that the rate of rise had doubled over three decades. That moment offered the perfect opportunity to compare real-world changes against projections made nearly thirty years earlier.

    Close call with predictions

    In 1996, the Intergovernmental Panel on Climate Change (IPCC) released its assessment report, just as satellite monitoring began.

    The report projected about 8 centimeters of sea-level rise over 30 years. The actual outcome was 9 centimeters, nearly identical.

    However, the models underestimated melting ice sheets by over 2 centimeters. Back then, the destabilizing effects of warming ocean waters on Antarctic ice were poorly understood. Greenland’s ice was also flowing into the ocean faster than anticipated.

    Components of sea-level rise

    The study shows that thermal expansion of seawater and melting of smaller glaciers were predicted fairly well. But contributions from Greenland and Antarctica were treated as negligible.

    In reality, these ice sheets accounted for nearly a quarter of observed sea-level rise. Another overlooked factor was groundwater depletion, which transferred more water to oceans than expected.

    Ignoring ice-sheets caused errors

    Early IPCC reports assumed that the dynamic behavior of ice sheets could be ignored for decades. This assumption proved incorrect. Later assessments that excluded dynamic ice flow produced unrealistically low projections.

    Once dynamic ice loss was included, estimates increased significantly. Modern assessments now highlight the “deep uncertainty” surrounding possible ice-sheet disintegration, which could drive sea levels far higher than expected.

    Past models were surprisingly accurate

    Thermal expansion was slightly overestimated, which balanced out the underestimated role of ice sheets.

    This created projections that, by chance, matched reality more closely than their flawed assumptions should have allowed.

    Still, the overall accuracy offers confidence in today’s more advanced models, especially since early reports successfully predicted atmospheric carbon dioxide levels.

    Future climate projections

    Predictions made in the 1990s have proven largely accurate, but the greatest challenges still lie ahead.

    Ongoing uncertainty about ice sheets and human emissions makes continuous monitoring vital for helping coastal societies prepare for what lies ahead.

    “Given the advances in both resolution and process understanding since the 1990s, the early success of the IPCC-SAR projection gives considerable confidence to climate projections for the future,” wrote the researchers.

    “Meanwhile, the importance of continued monitoring of all relevant components of the climate system by key agencies cannot be understated.”

    The study is published in the journal Earth’s Future.

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  • Scientists Discover Strange New Quantum Behavior in Superconducting Material

    Scientists Discover Strange New Quantum Behavior in Superconducting Material

    Researchers confirmed active flat bands in a kagome superconductor, opening new possibilities for designing quantum materials and future electronic technologies. (Artist’s concept). Credit: SciTechDaily.com

    A research team has provided the first experimental proof that flat electronic bands in a kagome superconductor are active and directly shape electronic and magnetic behaviors.

    Researchers from Rice University, working with international partners, have found the first clear evidence of active flat electronic bands within a kagome superconductor. The discovery marks an important step toward creating new strategies for designing quantum materials, including superconductors, topological insulators, and spin-based electronics, which could play a central role in advancing future electronics and computing.

    The findings, published on August 14 in Nature Communications, focus on the chromium-based kagome metal CsCr₃Sb₅, a material that becomes superconducting when placed under pressure.

    Kagome metals are defined by their unique two-dimensional lattice of corner-sharing triangles. Recent theories have suggested that these structures can host compact molecular orbitals, or standing-wave patterns of electrons, which may enable unconventional superconductivity and unusual magnetic states driven by electron correlation effects.

    In most known materials, such flat bands are positioned too far from the relevant energy levels to influence behavior. In CsCr₃Sb₅, however, they play an active role and directly shape the properties of the material.

    Pengcheng Dai, Ming Yi, and Qimiao Si of Rice’s Department of Physics and Astronomy and Smalley-Curl Institute, along with Di-Jing Huang of Taiwan’s National Synchrotron Radiation Research Center, led the study.

    Ming Yi
    Ming Yi. Credit: Jeff Fitlow/Rice University

    “Our results confirm a surprising theoretical prediction and establish a pathway for engineering exotic superconductivity through chemical and structural control,” said Dai, the Sam and Helen Worden Professor of Physics and Astronomy.

    The finding provides experimental proof for ideas that had only existed in theoretical models. It also shows how the intricate geometry of kagome lattices can be used as a design tool for controlling the behavior of electrons in solids.

    “By identifying active flat bands, we’ve demonstrated a direct connection between lattice geometry and emergent quantum states,” said Yi, an associate professor of physics and astronomy.

    Experimental Techniques and Findings

    The research team employed two advanced synchrotron techniques alongside theoretical modeling to investigate the presence of active standing-wave electron modes. They used angle-resolved photoemission spectroscopy (ARPES) to map electrons emitted under synchrotron light, revealing distinct signatures associated with compact molecular orbitals. Resonant inelastic X-ray scattering (RIXS) measured magnetic excitations linked to these electronic modes.

    “The ARPES and RIXS results of our collaborative team give a consistent picture that flat bands here are not passive spectators but active participants in shaping the magnetic and electronic landscape,” said Si, the Harry C. and Olga K. Wiess Professor of Physics and Astronomy, “This is amazing to see given that, until now, we were only able to see such features in abstract theoretical models.”

    Theoretical support was provided by analyzing the effect of strong correlations starting from a custom-built electronic lattice model, which replicated the observed features and guided the interpretation of results. Fang Xie, a Rice Academy Junior Fellow and co-first author, led that portion of the study. 

    Obtaining such precise data required unusually large and pure crystals of CsCr₃Sb₅, synthesized using a refined method that produced samples 100 times larger than previous efforts, said Zehao Wang, a Rice graduate student and co-first author.

    The work underscores the potential of interdisciplinary research across fields of study, said Yucheng Guo, a Rice graduate student and co-first author who led the ARPES work. 

    “This work was possible due to the collaboration that consisted of materials design, synthesis, electron and magnetic spectroscopy characterization, and theory,” Guo said.

    Reference: “Spin excitations and flat electronic bands in a Cr-based kagome superconductor” by Zehao Wang, Yucheng Guo, Hsiao-Yu Huang, Fang Xie, Yuefei Huang, Bin Gao, Ji Seop Oh, Han Wu, Jun Okamoto, Ganesha Channagowdra, Chien-Te Chen, Feng Ye, Xingye Lu, Zhaoyu Liu, Zheng Ren, Yuan Fang, Yiming Wang, Ananya Biswas, Yichen Zhang, Ziqin Yue, Cheng Hu, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, Makoto Hashimoto, Donghui Lu, Junichiro Kono, Jiun-Haw Chu, Boris I. Yakobson, Robert J. Birgeneau, Guang-Han Cao, Atsushi Fujimori, Di-Jing Huang, Qimiao Si, Ming Yi and Pengcheng Dai, 14 August 2025, Nature Communications.
    DOI: 10.1038/s41467-025-62298-5

    Funding: U.S. Department of Energy, Welch Foundation, Gordon and Betty Moore Foundation, Air Force Office of Scientific Research, U.S. National Science Foundation

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  • ‘Gives us a more complete picture’

    ‘Gives us a more complete picture’

    A team of researchers at École Polytechnique Fédérale de Lausanne — or the Swiss Federal Institute of Technology in Lausanne — recently created a database to help scientists monitor wildlife without ever entering their habitats. Called MammAlps, the “richly annotated, multi-view, multimodal wildlife behavior dataset” is a way for scientists to better understand wildlife behavior, according to an EPFL article published on Phys.org.

    To create the dataset, researchers set up nine cameras across the Swiss National Park, capturing more than 43 hours of raw footage. They then trimmed down this footage into 8 1/2 hours of highly detailed, labeled clips with the help of artificial intelligence. 

    Each clip includes in-the-moment annotations of wildlife behaviors across two levels: broader activities such as “foraging” or “playing,” and more detailed actions such as “sniffing” or “running.” As an animal’s behavior changes during a clip, the labels change accordingly, creating a real-time behavioral timeline.

    However, the database doesn’t just catalog video. It also includes audio recordings, environmental maps of natural features such as rivers and vegetation, and even documentation of weather conditions at the time.

    “This multi-modal approach gives us a more complete picture of wildlife behavior,” EPFL professor and project supervisor Alexander Mathis said in the article.

    While this detailed dataset could be a breakthrough in conservation, it’s worth noting that the use of AI comes at an environmental cost. Data centers powering AI require large amounts of electricity — often from dirty energy sources — and billions of gallons of water for cooling. AI hardware also relies on rare minerals and elements, which are often mined unethically and unsustainably, per the United Nations Environment Programme.







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    The growing demands of AI are expected to contribute to the doubling of data center power consumption from 2022 to 2026. 

    Still, researchers believe MammAlps could help conservationists to quickly identify significant wildlife behaviors in hundreds of hours of wildlife footage. By training AI on the dataset, the technology could automatically scan new recordings and extract the most relevant segments. This could help spot changes in animal behavior caused by climate shifts, human activity, or even disease, leading to more effective protection strategies — all without disturbing animals in the wild.

    The data collection isn’t over, either. The team is currently processing data collected in 2024 and plans to conduct more observations in 2025. These additional surveys will help expand recordings for rare species, including alpine hares and lynx. Additionally, researchers hope to analyze wildlife behavior over multiple seasons by expanding their observations.

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  • Watch SpaceX launch 5,000 pounds of cargo to the ISS early on Aug. 24

    Watch SpaceX launch 5,000 pounds of cargo to the ISS early on Aug. 24

    NASA’s SpaceX 33rd Commercial Resupply Services Launch – YouTube


    Watch On

    A SpaceX cargo ship laden with 5,000 pounds (2,270 kilograms) of supplies will launch to the International Space Station early Sunday morning (Aug. 24), and you can watch the action live.

    A robotic Dragon capsule is scheduled to lift off atop a SpaceX Falcon 9 rocket on Sunday at 2:45 a.m. EDT (0645 GMT) from Space Launch Complex 40 at Cape Canaveral Space Force Station in coastal Florida. The launch will kick off SpaceX’s 33rd mission for NASA’s Commercial Resupply Services program, hence the flight’s name: CRS-33.

    Coverage will start roughly 20 minutes before launch. You can watch it here at Space.com, courtesy of NASA, or via the space agency.

    a black and white rocket launches into a dark night sky

    A SpaceX Falcon 9 rocket launches a Dragon cargo spacecraft from Launch Complex 39A at NASA’s Kennedy Space Center in Florida on April 21, 2025, on the company’s 32nd commercial resupply services mission for the agency to the International Space Station. (Image credit: SpaceX)

    If the launch goes to plan, the CRS-33 Dragon will dock with the International Space Station (ISS) on Monday (Aug. 25) at the forward port of the Harmony module. Rendezvous coverage will begin on the same feeds starting at 6 a.m. EDT (1000 GMT), with docking scheduled for 7:30 a.m. EDT (1130 GMT).

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  • Atomistic mechanism of non-selective cation permeation in cyclic nucleotide-gated CNGA1 ion channel by molecular dynamics simulations

    Atomistic mechanism of non-selective cation permeation in cyclic nucleotide-gated CNGA1 ion channel by molecular dynamics simulations

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  • Scientists Build Scalable Network Node With Light and Ions

    Scientists Build Scalable Network Node With Light and Ions

    One by one, each ion-qubit is moved into an optical cavity, where mirrors efficiently collect the photons emitted by the ion-qubit. Each photon emerges entangled with its ion-qubit, forming a deep quantum link. Credit: Universität Innsbruck/Harald Ritsch

    The new interface paves the way for connecting quantum devices.

    Quantum networks are often described as the next stage of the internet. Instead of transferring ordinary digital information in bits, they use photons to carry quantum information. This approach could make communication virtually unbreakable, connect faraway quantum computers into one powerful system, and enable sensing technologies capable of measuring time and environmental conditions with extraordinary precision.

    For this kind of network to work, researchers must develop quantum network nodes that can both store quantum information and exchange it through light particles. In a recent breakthrough, a team led by Ben Lanyon at the Department of Experimental Physics, University of Innsbruck, demonstrated such a node by using a chain of ten calcium ions inside a prototype quantum computer.

    By finely controlling electric fields, the scientists guided the ions one at a time into an optical cavity. Inside the cavity, a carefully calibrated laser pulse caused each ion to emit a single photon, with the photon’s polarization becoming entangled with the ion’s quantum state.

    Linking Ions and Photons

    The process created a stream of photons; each tied to a different ion-qubit in the register. In future the photons could travel to distant nodes and be used to establish entanglement between separate quantum devices. The researchers achieved an average ion–photon entanglement fidelity of 92 percent, a level of precision that underscores the robustness of their method.

    “One of the key strengths of this technique is its scalability,” says Ben Lanyon. “While earlier experiments managed to link only two or three ion-qubits to individual photons, the Innsbruck setup can be extended to much larger registers, potentially containing hundreds of ions and more.” This paves the way for connecting entire quantum processors across laboratories or even continents.

    “Our method is a step towards building larger and more complex quantum networks,” says Marco Canteri, the first author of the study. “It brings us closer to practical applications such as quantum-secure communication, distributed quantum computing, and large-scale distributed quantum sensing.”

    Broader Applications

    Beyond networking, the technology could also advance optical atomic clocks, which keep time so precisely that they would lose less than a second over the age of the universe. Such clocks could be linked via quantum networks to form a worldwide timekeeping system of unmatched accuracy.

    Reference: “Photon-Interfaced Ten-Qubit Register of Trapped Ions” by M. Canteri, Z. X. Koong, J. Bate, A. Winkler, V. Krutyanskiy and B. P. Lanyon, 21 August 2025, Physical Review Letters.
    DOI: 10.1103/v5k1-whwz

    The work was financially supported by the Austrian Science Fund FWF and the European Union, among others, and demonstrates not only a technical milestone but also a key building block for the next generation of quantum technologies.

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  • This Week In Space podcast: Episode 174 — Gifts From Orbit

    This Week In Space podcast: Episode 174 — Gifts From Orbit

    Gifts From Orbit – With Lynn Harper – YouTube


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    On Episode 174 of This Week In Space, Rod Pyle and and Tariq Malik are joined by Lynn Harper to discuss some of the amazing research taking place aboard the International Space Station (ISS).

    The ISS has been serving as a major research center in space for over 25 years, but its time is coming to an end with a planned deorbit in 2030. Should we end this expensive experiment in space, or are we squandering a $150 billion resource? Dr. Harper, the Lead for Integrative Studies at the NASA Ames Space Portal, joins us to talk about the promising work done on cancer treatments, the growth of replacement retinas and the potential breakthroughs for treating Alzheimer’s disease. These and many more are the focus of our conversation. 


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  • 59 years ago today, the first photograph of Earth from lunar orbit was taken.

    59 years ago today, the first photograph of Earth from lunar orbit was taken.

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    On 23 August 1966, NASA captured the first photograph of the Earth as seen from a lunar orbit by its unmanned Lunar Orbiter 1 probe. This spacecraft had been launched on 10 August 1966 with a very specific mission: to photograph soft areas of the lunar surface for the selection and verification of safe landing sites for the Surveyor and Apollo missions.

    However, fate had something much bigger in store. Photographing the Earth was not part of the original mission, not even considered until the spacecraft was already in space. It was a spontaneous decision by the control team that would result in one of the most iconic images in the history of space exploration.

    The photograph was taken from a distance of approximately 380,000 kilometres and shows half of the Earth, from Istanbul to Cape Town, with the eastern areas submerged at night. Although the image revealed no details of the Earth’s surface when it was taken in 1966, its emotional and scientific impact was immediate and lasting.

    The technical legacy of a revolutionary image

    Lunar Orbiter 1 was equipped with a sophisticated 68-kilogram Eastman Kodak imaging system that used wide-angle lenses and had the unique ability to develop film, scan the images and send them back to Earth. In a twist that was not known until after the end of the Cold War, this camera had originally been developed by the US National Reconnaissance Office (NRO) and had previously flown on the Samos E-1 spy satellite.

    The original image was never recovered in its full resolution from the mission’s stored data. It was not until 2008 that the Lunar Orbiter Image Retrieval Project (LOIRP) managed to restore and significantly improve the quality of this historic photograph, revealing details that remained hidden for more than four decades.

    The Lunar Orbiter 1 mission ended on 29 October 1966, when it was deliberately crashed into the lunar surface to avoid interference with future missions. During its operational time, the spacecraft had successfully completed its main objectives, capturing a total of 205 images of the Earth’s natural satellite.

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  • DNA from our extinct cousins helped the first Americans survive

    DNA from our extinct cousins helped the first Americans survive

    Some of the first Americans carried more than tools and traditions, they also brought a small but powerful piece of DNA. That genetic fragment, inherited from an extinct hominin, appears to have helped early people cope with new diseases, foods, and landscapes.

    In a new study, a team of scientists led by the University of Colorado Boulder (CU Boulder), with collaborators including Brown University, traced a Denisovan-derived variant of a gene called MUC19 that is unusually common in people with Indigenous American ancestry.

    An incredible leap written in DNA


    “In terms of evolution, this is an incredible leap,” said Fernando Villanea, an assistant professor in the Anthropology department at CU Boulder and a lead author of the study. “It shows an amount of adaptation and resilience within a population that is simply amazing.”

    The result ties a deep past event to a much later journey. Long before humans crossed the Bering Strait ice corridors, Denisovans and Neanderthals interbred.

    Later, Neanderthals and humans did the same. Along that chain, a Denisovan version of MUC19 made its way into some human populations. Natural selection then favored it in the Americas.

    Extinct cousins left their mark

    Denisovans were close cousins of both humans and Neanderthals. They ranged from Siberia south toward Oceania and west onto the Tibetan Plateau. Fossil traces are sparse, and the first recognized Denisovan was identified only 15 years ago through DNA in a bone fragment.

    “We know more about their genomes and how their body chemistry behaves than we do about what they looked like,” Villanea said.

    Like Neanderthals, Denisovans may have had prominent brow ridges and lacked chins. What we know best is their genetic legacy. They left DNA behind in many modern people, shaping biology from immunity to altitude tolerance.

    Mucus DNA improved health

    MUC19 sits in a family of 22 mucin genes in mammals. These genes help build mucus, a frontline barrier that protects tissues and traps pathogens. “It seems like MUC19 has a lot of functional consequences for health, but we’re only starting to understand these genes,” said Villanea.

    Earlier work showed Denisovans carried a distinctive MUC19 sequence. Some modern humans inherited it. That kind of admixture was common in the ancient world.

    Most people today carry some Neanderthal DNA. Denisovan DNA can reach about 5 percent in people from Papua New Guinea.

    DNA reveals American adaptation

    Villanea and co-lead author David Peede examined already published genomes from people in Mexico, Peru, Puerto Rico, and Colombia. They asked a simple question with big implications: Where is the Denisovan MUC19 variant most common?

    The answer pointed to the Americas. Roughly one in three people of Mexican ancestry carries a copy of the Denisovan MUC19 variant.

    The signal is strongest on genomic segments that reflect Indigenous American heritage. In contrast, only about 1 percent of people with Central European ancestry carry it.

    Denisovan core, Neanderthal shell

    The team found another twist. The Denisovan segment sits inside a larger stretch of Neanderthal-derived DNA. “This DNA is like an Oreo, with a Denisovan center and Neanderthal cookies,” Villanea said.

    That sandwich points to the path this gene likely took. Denisovans first passed MUC19 to Neanderthals. Later, Neanderthals passed that package to humans.

    It is the first clear case of Denisovan DNA reaching humans through Neanderthals and not only through direct Denisovan–human mixing.

    DNA boosted first Americans

    After humans reached the Americas, selection seems to have boosted the Denisovan MUC19. Why here and not elsewhere? The first Americans faced environments unlike any their ancestors had known. New pathogens, new foods, new seasons and new terrains.

    A mucus-related gene that improved barrier defenses or mucosal health may have offered an edge.

    “All of a sudden, people had to find new ways to hunt, new ways to farm, and they developed really cool technology in response to those challenges,” noted Villanea. “But over 20,000 years, their bodies were also adapting at a biological level.”

    Ancient genes met new worlds

    The migration story spans ice, coastlines, and time. Early people moved from a shared ancestral population around the Bering Strait into a continent that contains rainforests, deserts, high mountains, and grasslands.

    “What Indigenous American populations did was really incredible,” Villanea said. “They went from a common ancestor living around the Bering Strait to adapting biologically and culturally to this new continent that has every single type of biome in the world.”

    Genes like MUC19 offer a record of that adaptation. They capture how ancient encounters with cousins like Denisovans left tools that descendants later used.

    Connecting past DNA to health

    The team now wants to test what different versions of MUC19 do in living people. Does the Denisovan variant change mucus properties in the mouth, gut, or airways? Does it alter infection risk or inflammation? Those answers would connect a striking evolutionary story to present-day health.

    For now, the lesson is broad. Human evolution is not a straight line. It is a braided river with tributaries from Neanderthals and Denisovans. Some of those tributaries carried genes that mattered when humans stepped into a new world.

    The first Americans adapted with ingenuity, culture, and technology – and, as this study shows, with a little help from very ancient DNA.

    The study is published in the journal Science.

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  • Webb discovered a new moon orbiting Uranus

    Webb discovered a new moon orbiting Uranus

    NASA’s James Webb Space Telescope has helped scientists discover a new moon orbiting Uranus, bringing the planet’s total to 29. The small moon was spotted on February 2, 2025, by a team from the Southwest Research Institute (SwRI).

    Scientists found the tiny moon in ten long-exposure images taken by NASA’s Webb Telescope. Though small, it’s a significant find, one that Voyager 2 missed when it flew past Uranus nearly 40 years ago.

    The new moon is incredibly small, only about six miles (10 kilometers) wide, based on how reflective it seems compared to Uranus’s other moons. Its tiny size likely made it too faint for Voyager 2 or earlier telescopes to detect, hiding in plain sight for decades.

    Matthew Tiscareno of the SETI Institute in Mountain View, California, a member of the research team, said, “No other planet has as many small inner moons as Uranus, and their complex inter-relationships with the rings hint at a chaotic history that blurs the boundary between a ring system and a system of moons.”

    “Moreover, the new moon is smaller and much fainter than the smallest of the previously known inner moons, making it likely that even more complexity remains to be discovered.”

    The newly discovered moon is the 14th in Uranus’s tightly packed group of small inner moons, orbiting closer to the planet than its five major moons—Miranda, Ariel, Umbriel, Titania, and Oberon. (Fun fact: all Uranian moons are named after characters from Shakespeare and Alexander Pope.)

    This tiny moon circles Uranus about 35,000 miles (56,000 kilometers) from its center, gliding between the orbits of Ophelia and Bianca. Its nearly perfect circular path hints that it likely formed right where it is, quietly holding its place in the planet’s complex lunar ballet.

    El Moutamid said, “Through this and other programs, Webb is providing a new eye on the outer solar system. This discovery comes as part of Webb’s General Observer program, which allows scientists worldwide to propose investigations using the telescope’s cutting-edge instruments. The NIRCam instrument’s high resolution and infrared sensitivity make it especially adept at detecting faint, distant objects that were beyond the reach of previous observatories.”

    Looking forward, the discovery of this moon underscores how modern astronomy continues to build upon the legacy of missions like Voyager 2, which flew past Uranus on January 24, 1986, and gave humanity its first close-up look at this mysterious world. Now, nearly four decades later, the James Webb Space Telescope is pushing that frontier even farther.”

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