Category: 7. Science

If you’ve ever dreamed of exploring space, you know there’ll be some serious dangers. One of them is posed by cosmic rays. These high-speed particles slam through anything, including our bodies, damaging DNA and ripping molecules apart. As dangerous as they sound to unprotected spacefarers, they could actually help microscopic life survive hiding under the icy surfaces of places like Europa or Enceladus.

A team of researchers led by Dimitra Atri at New York University’s campus in Abu Dhabi looked at the process of radiolysis, which occurs when cosmic rays slam into water or ice. The high-speed particles break water molecules apart, which releases electrons, and some bacteria on Earth use those for energy. Could the same thing happen to possible life forms on icy worlds of the outer Solar System?

That’s what Atri’s team wanted to know. Energetic radiation such as cosmic rays (and gamma rays) can reach the surface of terrestrial planets with thin atmospheres (think: Mars). It also has enough energy to ionize atoms and molecules on those worlds. That provides an energy source for forms of microbial life that can withstand high radiation levels. Some of them even thrive in such environments. So, it’s not a stretch to look at cosmic rays as a source of energy for such life on other worlds.

The Power of High-speed Particles

Cosmic rays deliver a powerful radiation punch. Most are made of hydrogen nuclei, although a smaller amount are helium or other elements. They come from several sources in the Universe. The Sun emits them, as do supernova explosions, clusters of massive, energetic stars, and even the busy regions around black holes. They travel at close to the speed of light and scientists are still studying all the ways they are energized. When they come into contact with Earth’s atmosphere, cosmic rays are usually blocked by our atmosphere. Occasionally some get through, and will strike atmospheric particles to create secondary showers of other particles that do reach the surface.

The Crab Nebula is the remains of a massive star that exploded thousands of years ago. It’s a source of cosmic rays. Credits: NASA/ESA/Arizona State University

High-speed particles such as cosmic rays play important roles in the Universe, from the generation of elements in interstellar space to activity that may have spurred the creation of life on Earth. Here at home, we often blame “cosmic rays” for computer glitches and other mishaps. Largely they pass right through us, but usually don’t cause damage. However, if we go out into space or enter very high altitudes (riding in a jet aircraft, for example), we’re faced with a larger number of them. Exploring near-Earth space, the Moon and beyond exposes us to very dangerous amounts of such cosmic radiation. Out there, astronauts have to shield themselves to avoid damage. It’s not just in space or on the Moon, either. Exploring Mars will expose people to a constant, life-long rain of cosmic rays, since the atmosphere is so thin and doesn’t provide a good shield.

Cosmic Rays and Icy Worlds

The Abu Dhabi team used computer simulations of cosmic ray strikes on icy worlds. The idea was to see how much energy radiolysis would produce on planets like Mars and the icy moons of Jupiter and Saturn. It turns out that Enceladus is a pretty good candidate for cosmic ray strikes on ice to produce enough energy to fuel possible life forms under its frozen surface. Mars could also be a potential life habitat benefitting from cosmic ray flux, as well as Europa.

The simulations inspired the idea of a “Radiolytic Habitable Zone” on those worlds. This would be a place in a planetary system where underground water (in the liquid or frozen form) could be energized by cosmic rays to produce energy for potential life. If this type of habitable zone could exist, that means there’d be a lot more places in the Universe where life could spring up, thanks to cosmic rays, according to Atri.

“This discovery changes the way we think about where life might exist,” said Atri. “Instead of looking only for warm planets with sunlight, we can now consider places that are cold and dark, as long as they have some water beneath the surface and are exposed to cosmic rays. Life might be able to survive in more places than we ever imagined.”

Life in More Places

Think about it. If cosmic radiation from these particles can spur the formation (or evolution) of life, then it widens the scope of the search for life by astrobiologists. Many icy worlds exist, even in our own Solar System. Astrobiology searches now focus largely on surfaces where life might be possible. They also look largely at so-called “habitable zones” where planets have liquid water on their surfaces.

Since cosmic rays can penetrate several meters beneath the surface of a world, that opens up a huge new range of habitats for life. Also, in the case of Europa, it means that this world – which is embedded in a high-radiation environment around Jupiter – could also be capable of harboring and sustaining life thanks to cosmic rays. The same would be true of Enceladus at Saturn.

On Mars, conditions are pretty inhospitable to surface life thanks to increased UV radiation, a very dry climate and extremely low temperatures. However, cosmic rays striking icy subsurface layers could stimulate other cycles there to provide a somewhat welcoming habitat for such life forms as halophiles (salt-loving microbes) that could exist in such an environment.

The team’s research provides a pathway in the search for life on distant worlds. This includes some where scientists might not have thought to look before now. That includes the subsurface regions of icy worlds – some of the darkest, coldest places in our own Solar System and beyond.

For More Information

Cosmic Rays Could Support Life Just Under the Ice

Estimating the Potential of Ionizing Radiation-induced Radiolysis for Microbial Metabolism on Terrestrial Planets and Satellites with Rarefied Atmospheres

Cosmic Rays: Particles from Outer Space

When her three-person submersible descended more than 30,000 feet into one of the Pacific Ocean’s deepest trenches, Mengran Du wasn’t sure what they would find.

What she saw, she recalled, was “unbelievable”: Dense clusters of tubeworms with tentacles tinged bloodred, jutting up like skyscrapers. Iridescent snails scaling the worms, like window washers. Bristly, white creatures wriggling between them like rush-hour commuters trying to get home for dinner.

An international team of researchers has discovered the world’s deepest known ecosystem sustained by chemicals seeping from the seafloor, submerged in water and darkness. The discovery expands the limits of where we know life can live on Earth.

“It’s a unique ecosystem,” said Dominic Papineau, an exobiologist who co-wrote the study on the deep-sea discovery published Wednesday in the journal Nature. “It’s a totally new thing that has not been seen before.”

The bottom dwellers, found in the Kuril-Kamchatka and Aleutian trenches, between Russia and Alaska, “alter our understanding of trench ecosystems,” said Lisa Levin, a professor emeritus of biological oceanography at Scripps Institution of Oceanography, who was not involved in the study.

For decades, scientists have studied organisms that thrive around hydrothermal vents, fissures spewing superheated fluids. But the creatures that live around cold seeps – places where gases such as methane and hydrogen sulfide ooze from the seafloor at near-freezing temperatures, often where tectonic plates meet – have been understudied.

So, to investigate, an expedition to the northwest Pacific last summer used the crewed submersible Fendouzhe to dive into the hadal zone, the ocean’s deepest region, named for Hades, the Greek god of the underworld.

China, the United States and others have been seeking to capitalize on the mineral wealth of the seafloor, mining metals for use in electric cars and other technology – and prompting concern about upending deep sea life.

The trenches examined in the new study are probably too deep for mining. Their exploration demonstrates newly acquired abilities by countries and companies to investigate the open ocean.

“People know very little about the bottom of the trench,” said Du, a geochemist with China’s Institute of Deep-sea Science and Engineering, which led the study. For decades, she added, researchers lacked the “high technology to enable us to go there.”

The researchers, once down there, found they weren’t alone. They discovered communities of animals dominated by marine tubeworms and mollusks spanning over 1,500 miles of total darkness.

Elsewhere on Earth, sunlight sustains life. Photosynthesis performed by plants or algae is the base of almost all food webs. Ocean scientists previously assumed trench creatures eked out an existence by feasting directly on dead animals and other organic matter that fell from sunlit parts of the ocean into the crevasses.

But in the hadal zone, life appears to sustain itself through a more meandering method.

Analysis of gases seeping from the seafloor suggests microbes are consuming organic matter that accumulates in the trenches and belching methane after their meals. Symbiotic bacteria inside the tubeworms and mollusks, in turn, absorb the methane and hydrogen sulfide from those cold seeps to produce organic matter to nourish their hosts.

The process, called chemosynthesis, may seem like an alien way for an animal to score dinner, but Papineau noted that humans have their own colonies of microbes that aid in digestion. “We ourselves have bacteria in our gut,” he said.

The researchers expect several of the specimens they plucked from the trenches will yield species new to science, though they don’t know how many. “This is the next paper,” Papineau said.

They also don’t know exactly how these animals survive the extraordinarily high pressures found in the trenches.

“They must have some trick, or they must have some unique metabolic pathway, to adapt to the high pressure,” Du said.

But the most surprising finding, according to biologist Lesley Blankenship-Williams, is about where all that nourishing methane is coming from: not from geological processes deep in the Earth, but from microbes in the sediment.

“Flourishing chemosynthetic communities had long been postulated to exist in the trenches, but this is the first paper that documents their existence below nine kilometers and at multiple locations,” said Blankenship-Williams, a professor at Palomar College in California who was not involved in the study.

The research team found life on 19 of 23 dives over a 40-day period, suggesting that hadal ecosystems may be common in Earth’s ocean trenches.

The extreme adaptability of organisms in those trenches gives hope to those searching for evidence of life in oceans on other worlds, such as Jupiter’s icy moon, Europa.

“There is about 3,700 million years of Earth evolution between the oldest animal fossils to the oldest microbial fossils,” Papineau said. “So, if deep extraterrestrial oceans existed for billions of years, then perhaps similar chemosynthetic-based ecosystems with animal-like creatures could also exist there.”

While Mars may be a dessicated place where water no longer flows, the planet still has glaciers slowly moving across its surface. Previously, it was thought that Martian glaciers were pure ice with a thin cover of rock and dust. But after 20 years of exhaustive research, scientists have concluded that glaciers all over the planet contain more than 80% water ice, meaning they are nearly pure. These findings could alter our understanding of Mars’ climate history and have significant implications for future crewed missions dependent on in-situ resource utilization (ISRU).

Yuval Steinberg, a recent graduate of the Weizmann Institute of Science, led the research team responsible for these findings. He was joined by Oded Aharonson and Isaac Smith, two senior scientists at the Planetary Science Institute (PSI) with faculty appointments at the Weizmann Institute of Science and York University, respectively. The paper detailing their findings, “Physical properties of subsurface water ice deposits in Mars’s Mid-Latitudes from the shallow radar,” recently appeared in the journal Icarus.

The team’s study focused on Lobate Debris Aprons (LDAs), ice-rich landforms found on slopes of massifs, primarily in the mid-latitudes on Mars. Previously, researchers believed that these glaciers were either “rock glaciers” with a water ice content of 30% or composed of near-pure water ice beneath a layer of debris. The team was inspired by past research, which revealed that the study of ice formations on Mars has been somewhat irregular. To address this, the team sought to develop a standardized method for analyzing glaciers based on two key factors.

An artist’s impression of the Mars Reconnaissance Orbiter using its Mars Climate Sounder instrument.Credit: NASA/JPL-CalTech

These included how quickly radar waves pass through them (their dielectric properties) and how quickly energy from radar waves dissipates into them (their loss tangent). Using this method, the team selected five LDAs on Mars that were studied by the SHAllow RADar (SHARAD) instrument aboard the Mars Reconnaissance Orbiter (MRO). This allowed them to draw comparisons between glaciers located all across the planet, which revealed that all had virtually identical properties. As Smith explained in a PSI press release:

Different techniques had been applied by researchers to various sites, and the results could not be easily compared. One of the sites in our study had never been studied, and at two of the five sites we used, only partial analysis had been completed previously. This is important because it tells us that the formation and preservation mechanisms are probably the same everywhere. From that, we can conclude that Mars experienced either one widespread glaciation or multiple glaciations that had similar properties. And, by bringing together these sites and techniques for the first time, we were able to unify our understanding of these types of glaciers.

Using this method, researchers can infer the ratio of rock to ice within, which cannot be done using visual observations of dust and rock-covered glaciers alone. Understanding the minimum purity of Martian glaciers will lead to a better understanding of the processes that form and preserve them, and will help when it comes time to plan for crewed missions. Per NASA’s mission architecture, landing site selection will need to account for the availability of essential resources, such as water ice. Aside from providing crews with a local source of drinking water, this ice can be fashioned into oxygen gas and rocket propellant.

“This study highlights how NASA programs are advancing science not just within the United States, but also reaching students around the world,” said Aharonson. For their next step, the team will look for additional glaciers to conduct more global comparisons, which will further augment our understanding of these debris-covered icy masses.

Further Reading: PSI, Icarus

How can identifying land on exoplanets help scientists better understand whether an exoplanet could harbor life? This is what a recently submitted study hopes to address as a team of researchers investigated how identifying land on exoplanets could help dispel waterworld false positives, which occur when the data indicates an exoplanet contains deep oceans (approximately 50 Earth oceans), hence the name “waterworld”. This study has the potential to help scientists develop more efficient methods for classifying exoplanets and their compositions, specifically regarding whether they contain life as we know it, or even as we don’t know it.

For the study, the researchers analyzed spectral data obtained from the United States Geological Survey (USGS) spectral library, with the exception of desert sand and ice. The goal of the study was to ascertain if the proposed next generation space telescope, Habitable Worlds Observatory (HWO), would be able to detect land masses on rocky exoplanets. In the end, the researchers determined that HWO would need a telescope size of approximately 8 meters (26 feet) to detect land masses based on signal-to-noise (SNR) data within the visible and ultraviolet wavelengths, while also building a case for HWO’s abilities for detecting oxygen biosignatures.

The study notes in its conclusions, “Detecting land via reflected light spectroscopy can help HWO rule out O2 biosignature false positives associated with the suppression of O2 sinks due to extremely deep oceans. Land detection is possible because all likely land surfaces for exo-Earth analogs have a positive sloping reflectance spectrum in the visible, whereas liquid water and water ice/snow are flat or slope negatively, respectively.”

As noted, HWO is a proposed next generation space telescope mission aimed to be the most powerful space telescope built that succeeds NASA’s James Webb Space Telescope (JWST). HWO planned capabilities include imaging objects in the optical, infrared, and ultraviolet wavelengths with its primary goal being to directly image a minimum of 25 habitable exoplanets. Despite HWO not being slated to launch until the 2040s, scientists and engineers continue to develop the technologies necessary for HWO to complete its mission and identify a habitable world beyond Earth.

Current waterworld exoplanet candidates include exoplanets (and distances from Earth) orbiting TRAPPIST-1 (40 light-years) and Kepler-11 (2,110 light-years), along with Kepler-62e (1,200 light-years), Kepler-62f (1,200 light-years), Kepler-22b (587 light-years), and GJ 1214b (40 light-years). Most recently, a 2024 study published in The Astrophysical Journal Letters announced JWST had discovered a “steam world” identified as GJ 9827d, which resides approximately 97 light-years from Earth and whose radius is slightly less than two Earths. What makes GJ 9827d intriguing is while its atmosphere is comprised of steam, the planet itself is estimated to be too hot to support life as we know it.

While the number of waterworld exoplanets are currently limited, this recent study comes as the number of confirmed exoplanets within our Milky Way Galaxy is rapidly approaching 6,000, which currently includes 219 terrestrial (rocky) exoplanets and 1,746 super-Earths like GJ 9827d. While JWST is powerful enough to analyze exoplanet atmosphere compositions, HWO could begin a new era in exoplanet discovery and exploration by directly imaging habitable worlds and potentially discovering an exoplanet capable of supporting life as we know it, or even as we don’t know it.

What new discoveries about identifying land on exoplanets will researchers make in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

CAPE CANAVERAL, Fla. — SpaceX’s Crew-11 astronaut mission to the International Space Station for NASA is go for launch.

When Crew-11 launches, a SpaceX Falcon 9 rocket will lift off from historic Launch Complex 39A here at NASA’s Kennedy Space Center (KSC), sending a crew of four the ISS for a six-month stay. Mission managers with NASA and SpaceX all polled ‘go’ to proceed to count down towards a 12:09 p.m. ET (1609 GMT) launch attempt of the Crew-11 mission on Thursday (July 31).

This splash of paint on the canvas of space is the planetary nebula NGC 6072, the dying embers of a ruined star that has reached the end of its sun-like life. Cocooned inside the nebula, within its own ejected outer layers, the fading star is undergoing a transformation into a white dwarf.

As the James Webb Space Telescope (JWST) shows in these two images, one taken in shorter-wavelength, near-infrared light and the other at mid-infrared wavelengths, the shape of the nebula is surprisingly complex— suggesting there’s more going on than meets the eye.

FOR IMMEDIATE RELEASE from the UNIVERSITY OF TORONTO

July 30, 2025

Researchers identify protein that evolved to enable land plants to thrive

TORONTO, ON – Evolutionary plant biologists at the University of Toronto (U of T) have identified a protein that evolved approximately 500 million years ago, enabling plants to convert light into energy through photosynthesis as they moved from aquatic environments to land.

The discovery provides a target for sustainable herbicides against parasitic plants and other weeds and may help boost food security by increasing the efficiency of photosynthesis in crops.

Using genome analysis and CRISPR gene editing, the researchers pinpointed Shikimate kinase-like 1 (SKL1) as a protein present in all land plants— but no other organisms — and showed the protein evolved from the Shikimate kinase (SK) enzyme to play an essential role in forming the chloroplasts needed for photosynthesis.

“One of the fundamental questions we investigate in this study is: what were the initial events that contributed to simple aquatic organisms moving onto land” says Michael Kanaris, lead author of the paper published recently in Molecular Biology and Evolution .

“A role for SKL1 in chloroplast biogenesis has previously been determined in Arabidopsis, a flowering plant studied extensively in modern laboratories. However, the biological function for SKL1 has not been established in early land plants.”

Kanaris conducted the research with Professor Dinesh Christendat in the Department of Cell & Systems Biology in the Faculty of Arts & Science at U of T, whose work focuses on the evolution of new protein functions. When DNA replication errors result in two identical copies of a protein, one copy may take on new functions as organisms adapt to changing environments over millions of years of evolution.

One example is the SKL1 protein in flowering plants, which originated as a copy of the SK protein, but gained a new function. Christendat’s prior research determined that flowering plants — evolving approximately 130 million years ago — became stunted and albino without SKL1 due to defective chloroplast development that impairs photosynthesis.

To look even further back into the evolution of land plants, the researchers used CRISPR genome editing to disrupt SKL1 function in common liverworts, which were among the first plants to colonize land about 500 million years ago. The team then put liverwort SKL1 into an albino flowering plant lacking SKL1, which resulted in seedlings that grew a green set of leaves with rescued chloroplasts.

The result was so unexpected that the researchers repeated the experiment several times. They confirmed that liverworts with disrupted SKL1 are pale and have stunted growth, just like flowering plants lacking SKL1, suggesting SKL1 might have the same function in chloroplast development in a plant significantly older than more modern flowers.

“My colleagues and I were astonished because liverworts are a very ancient plant species,” says Christendat. “We assumed that the way SKL1 functions in liverwort would be very different to a more recently evolved plant. Not only is SKL1 function conserved over 500 million years of plant evolution, it is also essential for their existence on land.”

The researchers note that while all land plants have SKL1 — as revealed by an analysis of gene sequences from diverse liverworts, ferns, mosses and flowering plants — ancestors to modern-day plants including water-living algae have only the original SK protein.

“The inability to identify SKL1 in organisms predating land plants suggests an important role for this gene coinciding with the emergence of terrestrial plants,” says Kanaris.

Christendat says knowing the role SKL1 plays in photosynthesis could both improve the ability to grow crops and make it a more effective target for new generations of herbicides, as the metabolic pathway that involves the SK protein is the current target of most herbicides. “Certain domains of the SKL1 protein vary across plants, so it may be possible to target SKL1 from specific plants to ensure safety and agricultural sustainability.”

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The familiar catalog of matter – solid, liquid, gas, plasma, BEC – just gained a new entry thanks to a custom crystal grown in the laboratory. This new quantum matter phase occurs when electrons and the positive “holes” they leave behind lock into pairs that swirl together in the same spin direction, creating a fluid of light-emitting quasiparticles.

“It’s a new phase of matter, similar to how water can exist as liquid, ice or vapor,” said Luis A. Jauregui, professor of physics and astronomy at UC Irvine.

His team outlines the evidence in a recently published study, staking a claim that moves a half-century-old theory from speculation to the lab bench.

New phase from electron-hole pairs

Researchers first proposed the excitonic insulator in 1965, arguing that a strong enough pull between electrons and holes would cause them to bind and open an energy gap that halts ordinary conduction.

The twist in the Irvine work is that the pairs align their spins rather than cancel them, forming a spin triplet condensate hinted at only in thought experiments until now.

Fresh reviews note that solid evidence for any excitonic insulator has remained elusive because most candidate materials freeze or destabilize before the necessary correlations emerge.

By coaxing a narrowly gapped crystal into the “ultra-quantum limit,” the new experiment clears that hurdle and offers a platform stable at a few kelvin, a temperature range reachable with common cryostats.

The resulting liquid is not a superconductor, yet its charge-neutral pairs can flow without the scattering that heats conventional circuits.

That distinction excites engineers who hunt for ways to move data with spin or valley degrees of freedom rather than raw charge.

Hafnium pentatelluride breaks the rules

The team built their sample from Hafnium pentatelluride, a layered topological material previously known for anomalous thermoelectric behavior.

Strong spin-orbit coupling in the telluride lattice narrows the band gap to fractions of an electron volt, making it fertile ground for electron-hole attraction.

Postdoctoral researcher Jinyu Liu cut the crystal into Hall-bar devices and added gold contacts thinner than a human hair.

The delicate patterning, carried out in Irvine’s cleanroom, preserved the material’s pristine layers while allowing two-terminal transport tests under extreme magnetic fields.

“If we could hold it in our hands, it would glow a bright, high-frequency light,” remarked Jauregui, hinting at the virtual photons tied to each bound pair. The comment highlights how the phase mixes electronic and optical properties in ways still being mapped.

Phase change confirmed in lab

With help from the Los Alamos National Laboratory (LANL), the group exposed the devices to a 70-tesla pulse, roughly 700,000 times stronger than Earth’s field.

Resistance along the current path jumped by orders of magnitude, while the Hall signal collapsed toward zero, classic fingerprints of an insulating state.

Landau quantization simplifies the spectrum in such fields, forcing carriers into discrete Landau levels. Past a critical field, the two lowest levels, one for spin-up electrons, one for spin-down holes, cross and hybridize.

Modeling by theorist Shi-Zeng Lin shows that the crossing seeds the spin-triplet gap measured at about 250 micro-electron-volts.

Because the gap is tied to spin alignment, it survives minor disorder that would kill a conventional charge gap. That resilience hints at practical robustness missing from many fragile quantum phases.

Why does any of this matter?

Using spins instead of electric charges to carry information could cut down on heat in computer chips, which is a major goal for researchers in spintronics.

These special spin-aligned pairs don’t carry any net charge, so they aren’t disrupted by stray electric fields that often cause problems in tiny circuits.

Some scientists think these pairs could even allow spin to flow smoothly without resistance, like how liquid helium flows without friction.

If that’s true, it could lead to strange and useful effects that have only been seen in a few advanced systems, opening the door to new types of tech.

Power without plugs

Exciton liquids naturally couple to light. In Hafnium pentatelluride, recombination is expected to emit photons in the ultraviolet range that can be harvested by integrated diodes.

A chip that recycles this light back into electrical work would, in principle, top itself up while idling, a vision sometimes called a “self-charging computer.”

This idea fits well with brain-inspired computer designs that use low-power memory components instead of energy-hungry traditional circuits.

Recent tests show that spin-based parts can switch using extremely small amounts of energy, much less than what today’s standard chips need.

Electron-hole pairs and space tech

Deep space is awash in protons and heavy ions that flip bits and pummel silicon. Radiation-tolerant design often adds shielding, redundant logic, and hardened gates, all at weight and cost penalties.

A condensate made of neutral pairs sidesteps many single-event upsets because incoming particles interact mainly through charge.

Topological protections further suppress backscattering, according to modeling of magnetic 2D heterostructures that remain stable after megarad doses.

Shieldless computers would lighten probes to Mars and beyond, and their longer lifetimes would shrink the spare-parts budgets of satellite constellations.

Industry already hunts for components that tolerate 1.5 billion-rad totals, a bar this phase could help clear.

Where the science heads next

Jauregui’s group plans to grow wider samples to check whether the phase supports edge currents that could be braided for fault-tolerant qubits.

They also aim to tweak the telluride stoichiometry, nudging the band overlap so the triplet forms at lower fields reachable with tabletop magnets.

Devices that layer hafnium pentatelluride between magnetic or superconducting materials might reveal new ways electron-hole pairs and other particles interact inside the material.

These setups could give engineers new tools for building tiny switches that use just a small amount of spin energy to turn on and off.

Finally, collaborators at the National High Magnetic Field Laboratory are designing long-pulse coils to probe the condensate’s lifetime. If the phase lingers after the field ramps down, chips could run in everyday labs instead of billion-dollar magnets.

The study is published in Physical Review Letters.

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