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I have to admit that my favorite superhero as a kid, and still today, is Spider-Man (and yes, that’s the correct spelling). There are a number of narrative reasons for this that I grew to appreciate more as I aged. First, Spider-Man is in the sweet spot of super abilities – he is strong, fast, agile, and has “spidey senses”. But he is not boringly invulnerable like Superman. He doesn’t brute force his way to solving situations. You don’t have to retcon questions like – if Ironman has the technology to produce immense energy, why doesn’t he just make it available to the world? He would save more lives that way.

But of course the coolest aspect of Spider-Man is his webslinging. This allows him to fly through the city, and to tie-up villains for the police to collect. This is also one aspect of the Spider-Man story that I thought was a bit contrived (even for the superhero genre where being bitten by a radioactive spider gives you super powers). In science fiction you generally get one gimmie – the author is allowed to make up just one fantastical fact to use as a cornerstone of their story. But they should not introduce multiple such gimmies. It breaks the unwritten contract between author and reader.

With Spider-Man, the one gimmie is the whole radioactive spider thing. That’s the one thing we are being asked to just accept and not question. I do like how more modern versions of the story changed that to genetic engineering – still fantastical, but way more plausible than radioactivity. I also liked that in the Tobey Maguire Spider-Man his webbing was part of the genetic engineering, and he produced the spider silk himself and extruded it from spinners in his wrists. For other versions we are asked to accept a double-gimmie – first, the whole spider thing, and second that Peter Parker also happens to be such a genius that he invented practically overnight something that scientists have been unable to do in decades, mimic the spider silk-spinning of spiders. Spider-Man was created in 1962, and here we are more than 60 years later and this remains an intractable problem of material science.

Or is it?

OK, we are not there quite yet, but scientists have made a significant advance in artificially creating strands of silk. The problem has always been spinning the silk into threads. We can genetically engineer animals to produce spider silk, but it comes out as a glob. Spiders, however, are able to keep their silk a liquid, and then extrude it from their spinnerets as threads with variable properties, such as stickiness. We really want to be able to do this artificially and at scale because spider silk is really strong – depending on what type of strength you are talking about, spider silk can be as strong or stronger than steel. When you hear this statistic, however, that often is referring to specific strength, because spider silk is much lighter than steel, it is stronger per unit weight than steel. In any case – it’s strong.

Perhaps a better comparison is Kevlar. Spider silk has several advantages over this modern material – it is more resilient, flexible, and in some cases tougher. But we are still not close to spinning spider-silk bullet-proof vests.

The current study has a title that does not betray its possible significance – Dynamic Adhesive Fibers for Remote Capturing of Objects. That’s a technical way of saying – you can shoot freaking spider webs. What the researchers found is that if you take a liquid silk from B. mori, which is a domestic silk moth, and combine it with a solvent like alcohol or (as in this case) acetone, it will become a semi-solid hydrogel. But the process takes hours. You can’t have your villain waiting around for hours for the webbing to solidify. But, if you also add dopamine to the mix, the dopamine helps draw water away from the silk quickly, and the solidification process becomes almost instant. Shoot this combination as a stream and the acetone evaporates in the air while the dopamine draws away the water and you have -an instant sticky string of silk. You can literally shoot this at a object at range and then pick it up. The silk will stick to the object.

This is a massive advance, figuring out a key component to the process. Spiders and silk-producing insects also use dopamine in the process. Spiders generally don’t shoot their webs. They adhere it to an anchor and then draw it out. So in a way they have done spiders one better. But the real goal is making artificial silk that can then be made into fibers that can then be made into stuff.

Now, the main limiting factor here – spider silk is still about 1000 times stronger than the resulting silk in this study. It’s strong and sticky enough to pick up small objects, but it’s not going to replace Kevlar. But the authors point out – the properties of this silk are “tunable”. They write:

“Furthermore, the possibility of tuning these properties is demonstrated by adding chitosan (Ch) and borate ions (BB), leading to remarkable mechanical and adhesive performances up to 107 MPa and 280 kPa, respectively, which allows the retrieval of objects from the ejected structure. This process can be finely tuned to achieve a controlled fabrication of instantaneously formed adhesive hydrogel fibers for manifold applications, mimicking living organisms’ ability to eject tunable adhesive functional threads.”

Spider silk has a tensile strength of about 1 GPa, so that is still 100 times this silk. Of course, they are just getting started. The hope is that further research will reveal formulas for tuning the properties of this silk to make it super strong, or have whatever other properties we need. I don’t want to trivialize this. As I have frequently pointed out – when scientists say “all we have to do is” they really mean “there is a huge problem we cannot currently fix, and may never be able to fix.”

It’s possible this method of spinning silk fibers may end up being little more than a laboratory curiosity, or may have a few niche applications at best. It is also possible this is the beginning of the next plastic or carbon fibers. Probably we will end up somewhere in between. But I am hopeful. There is a reason material scientists have been trying to crack the spider silk puzzle for decades – because the potential is huge. This really is an amazing material with incredible potential.

The post Spider-Man’s Web Shooter first appeared on NeuroLogica Blog.

Autonomous taxis are already operating on US streets, while Elon Musk has spent years promising a self-driving car and failing to deliver. The newly announced Tesla Cybercab is unlikely to change that

The UK government's decision to return the Chagos Islands to Mauritius surprisingly threatens the extinction of millions of website addresses ending in ".io", and no one is quite sure what will happen next

In the opening to Rachel Kushner's Booker-shortlisted novel Creation Lake, the latest pick for the New Scientist Book Club, we meet undercover operative Sadie Smith as she secretly reads the emails of an eco-activist group

It's Skeptoid's 18th birthday! Won't you help us celebrate by giving us a little birthday present?

It doesn't bode well for the future that "leaders" of major American institutions look at naked emperors and compliment them on their beautiful clothes.

The post The President of Stanford Wants Us To Debate Which Number is Larger, 9 or 133 first appeared on Science-Based Medicine.

Scientists have discovered a low-cost method to significantly reduce this pollution from hydrogen internal combustion engines by improving the efficiency of their catalytic converters. The researchers found that infusing platinum in catalytic converters with a highly porous material called Y zeolites greatly enhances the reactions between nitrogen oxides and hydrogen, converting unhealthful nitrogen oxides into harmless nitrogen gas and water vapor.

Researchers have observed electric charges traveling across the interface of two different semiconductor materials. Using scanning ultrafast electron (SUEM) techniques, the research team has directly visualized the fleeting phenomenon for the first time.

Researchers have observed electric charges traveling across the interface of two different semiconductor materials. Using scanning ultrafast electron (SUEM) techniques, the research team has directly visualized the fleeting phenomenon for the first time.

Per- and polyfluoroalkyl chemicals, known commonly as PFAS, could take over 40 years to flush out of contaminated groundwater.

Chemists have developed a new chemical reaction that will allow researchers to synthesize selectively the left-handed or right-handed versions of 'mirror molecules' found in nature and assess them for potential use against cancer, infection, depression, inflammation and a host of other conditions.

The small island nations of the South Pacific are facing the harsh reality of sea level rise. Within 50 years they will be swamped by rising seas linked to climate change. That’s part of a stark forecast from a sea level change science team at NASA and leading universities.

The group used satellites to predict rising ocean levels. According to their data, Pacific nations such as Tuvalu, Kiribati, and Fiji will experience an increased rise in sea levels. That threatens the homes and livelihoods of millions of people.

The Team’s Work

The team that examined the rise of sea levels threatening South Pacific nations is part of an interdisciplinary research group at NASA. Its job is to improve our understanding of sea-level change over time. The members analyzed the South Pacific threat at the request of the affected nations and coordinated with the U.S. State Department. They created high-resolution maps showing which areas of different Pacific Island nations would be vulnerable to high-tide flooding. The maps outline the potential for flooding. In addition, they take into account different greenhouse gas emissions scenarios, ranging from best-case to business-as-usual to worst-case.

One of the islands of Tuvalu. Sea level rise threatens to swamp the islands of this nation within 50 years. Courtesy NASA.

A combination of space-based and ground-based measurements can yield more precise sea level rise projections. That should give an improved understanding of the impacts on countries in the Pacific. Still, it’s one thing to create predictive models and share that data with affected nations. It’s quite another to actually experience the gradual rise of sea levels as the people of the South Pacific islands and other low-lying areas along the world’s coastlines.

“I am living the reality of climate change,” said Grace Malie, a youth leader from Tuvalu who is involved with the Rising Nations Initiative, a United Nations-supported program led by Pacific Island nations to help preserve their statehood and protect the rights and heritage of populations affected by climate change. “Everyone (in Tuvalu) lives by the coast or along the coastline, so everyone gets heavily affected by this.”

How NASA Tracks Sea-level Rise

Researchers from the University of Hawaii, the University of Colorado, and Virginia Tech all took part in the study, which used a new Pacific Islands Flooding Tool for the project. The data they use comes from measurements by satellites, shipboard and airborne instruments, and supercomputer analysis. The result is a more precise assessment of sea levels and their rise and fall over time. Using this data, the science teams found some worrying trends.

The portal to NASA’s Pacific Islands flooding analysis tool to help scientists assess sea level rise in low-lying areas. Courtesy NASA.

“Sea level will continue to rise for centuries, causing more frequent flooding,” said Dr. Nadya Vinogradova Shiffer, who directs ocean physics programs for NASA’s Earth Science Division. “NASA’s new flood tool tells you what the potential increase in flooding frequency and severity look like in the next decades for the coastal communities of the Pacific Island nations.”

What Affects Sea Level?

Sea level rise is based on a number of factors, including melting of glaciers and other ice packs and ocean warming related to pumping greenhouse gases into the atmosphere. Based on the data from NASA satellites, the Pacific Islands most at risk will see at least a 15-cm sea level rise by 2050. That’s nearly an order of magnitude higher than all Pacific Island nations experience now. To give you an idea of how that will affect specific places, Tuvalu currently sees less than five high tide flood days per year. By 2050, residents will experience at least 25 flood days each year. Kiribati will see 65 flood events. The maps produced by the NASA-led team for these and other islands should help these nations plan for future flood mitigation efforts.

“Science and data can help the community of Tuvalu in relaying accurate sea level rise projections,” said Malie. “This will also help with early warning systems, which is something that our country is focusing on at the moment.”

Assessing Sea Level Rise

Not every area in the world experiences the same amount of flooding. Local conditions and coastlines contribute to area-specific floods. The impact that 15 centimeters of sea level rise will have varies from country to country. Some regions will see nuisance flooding several times a year in flat or low-lying areas. Others face inundation for longer periods with higher amounts of water.

“We’re always focused on the differences in sea level rise from one region to another, but in the Pacific, the numbers are surprisingly consistent,” said Ben Hamlington, a sea level researcher at NASA’s Jet Propulsion Laboratory in Southern California and the agency’s sea level change science team lead.

The impacts of sea level rise will vary from place to place and depend on topography, shapes of coastlines, and other factors. Better predictive tools will help scientists understand where sea levels will rise the most and share that information with affected populations. Researchers would like to combine satellite data on ocean levels with ground-based measurements of sea levels at specific points, as well as with better land elevation information. “But there’s a real lack of on-the-ground data in these countries,” said Hamlington.

Real-world Experience

The combination of space-based and ground-based measurements can yield more precise sea level rise projections and an improved understanding of the impacts on countries in the Pacific. Still, it’s one thing to create predictive models and share that data with affected nations. It’s quite another to actually experience the gradual rise of sea levels as the people of the South Pacific islands and other low-lying areas along the world’s coastlines.

People in these regions experience different types of threats from the oceans. Flooding can occur when the ocean inundates the land during tropical storms, typhoons, and hurricanes. It can also happen during exceptionally high tides, called king tides.

An example of sunny day king tide flooding submerging street infrastructure outside the City of Miami Fire Station 13. Sea level rise contributes to increased incidences of such flooding. Credit: Mike Sukop/NOAA.

Another avenue for flooding is saltwater intrusion into underground areas. That pushes the water table to the surface. “There are points on the island where we will see seawater bubbling from beneath the surface and heavily flooding the area,” Malie added.

Places like Tuvalu will benefit from better tools to predict sea level rise. It’s not just a matter of preventing flooding, but one of a nation’s survival now and over the next few decades. “The future of the young people of Tuvalu is already at stake,” said Malie. “Climate change is more than an environmental crisis. It is about justice, survival for nations like Tuvalu, and global responsibility.”

For More Information

NASA Analysis Shows Irreversible Sea Level Rise for Pacific Islands
Sea Level Change
Pacific Islands Flooding Tool

The post Satellites are Tracking the Ongoing Sea Level Rise Swamping Pacific Island Nations appeared first on Universe Today.

In recent years, the number of known extrasolar planets (aka. exoplanets) has grown exponentially. To date, 5,799 exoplanets have been confirmed in 4,310 star systems, with thousands more candidates awaiting confirmation. What has been particularly interesting to astronomers is how M-type (red dwarf) stars appear to be very good at forming rocky planets. In particular, astronomers have detected many gas giants and planets that are several times the mass of Earth (Super-Earths) orbiting these low-mass, cooler stars.

Consider TOI-6383A, a cool dwarf star less than half the mass of the Sun that orbits with an even smaller, cooler companion – the red dwarf star TOI-6383B. In a recent study, an international team of astronomers with the Searching for Giant Exoplanets around M-dwarf Stars (GEMS) survey detected a giant planet transiting in front of the primary star, designated TOI-6383Ab. This planet is similar in size and mass to the system’s companion star, which raises questions about the formation of giant planets in red dwarf star systems.

The team was led by Lia Marta Bernabò, a PhD astronomy student at the University of Texas at Austin (UTA) and the German Aerospace Center (DLR). She was joined by colleagues with the GEMS collaboration, which includes astronomers from the Center for Planetary Systems Habitability, the Carnegie Science Earth and Planets Laboratory, the Center for Exoplanets and Habitable Worlds, the ETH Zurich Institute for Particle Physics & Astrophysics, the Anton Pannekoek Institute for Astronomy, NOIRLab, the NASA Goddard Space Flight Center, and multiple universities and institutes. The paper that details their findings was recently accepted for publication by the Astronomical Journal.

A giant star orbits one of the stars in the binary star system TOI-6383. As both stars are dwarf stars, a problem due to the mass budget comes up. Credit: DLR

The TOI6383 system consists of two red dwarf stars located about 560 light-years from Earth. The primary (A) is about 46% as massive as the Sun and about as large and has an estimated surface temperature of 3444 K (3,170 °C; 5,740 °F) – about 60% of the Sun’s surface temperature. Its companion (B) is 20.5% as massive as our Sun, 22% its size, and has an estimated surface temperature of 3121 K (2848 °C; 5,158 °F). Meanwhile, TOI6383Ab has a mass and size comparable to Jupiter and an orbital period of about 1.79 days.

Based on the all-sky coverage of NASA’s Transiting Exoplanet Survey Satellite (TESS), the GEMS survey team is dedicated to searching for giant exoplanets around M-dwarf stars (GEMS) using the Transit Method (Transit Photometry). This consists of monitoring stars for periodic dips in brightness, which could indicate planets passing (aka transiting) in front of their parent stars relative to the observer. The exoplanet was detected by TESS and confirmed by a combination of follow-photometry and radial velocity measurements using ground-based telescopes.

This survey aims to test theories of how planets form, which can be divided into two main categories. The first scenario is the core-accretion model, where planetesimals coagulate around a massive core. However, this model has come to be questioned in recent decades, largely because it is inconsistent with the mass budget and time scales for the formation of M dwarfs. Dwarf stars typically have less massive protoplanetary disks around them, meaning there is insufficient material to form giant planets.

The second scenario is the rapid formation model, where a massive protostellar disk disintegrates into clumps under its own gravity, which then accrete material and form planets. The discovery of this latest massive planet around a low-mass star will help astronomers to test these competing models. To date, only 20 massive exoplanets have been detected around M-type red dwarfs. The GEMS survey seeks to increase this inventory to at least 40, whereupon more precise tests of these models can be made.

Further Reading: DLR Institute of Planetary Research, Astronomical Journal

The post Exoplanet Discovered in a Binary System Could Explain Why Red Dwarfs Form Massive Planets appeared first on Universe Today.

A new technique uses glowing molecules, laser light and microscopes to measure distances as minuscule as 0.1 nanometres – the width of a typical atom

When three massive objects meet in space, they influence each other through gravity in ways that evolve unpredictably. In a word: Chaos. That is the conventional understanding. Now, a researcher has discovered that such encounters often avoid chaos and instead follow regular patterns, where one of the objects is quickly expelled from the system. This new insight may prove vital for our understanding of gravitational waves and many other aspects of the universe.

A new solution deposition process for semiconductors yields high-performing transistors by introducing more defects, counterintuitively. Researchers used these devices to construct high- speed logic circuits and an operational high-resolution inorganic LED display.

When lightning cracks on Earth, especially high-energy electrons may fall out of Earth's inner radiation belt, according to a new study -- an electron 'rain' that could threaten satellites, and even humans, in orbit.

An organic catalyst offers chemists precise control over a vital step in activating hydrocarbons.

Reader Nick sent me this 4-minute video about a young Indian girl—only ten years old—has become an accomplished wildlife photographer. I’ve started the video at the point at which her “PBS News Weekend” piece begins. It’s a short video but a heartwarming one, and this young woman is going to go far.  It doesn’t hurt that she has access to some of the most charismatic wildlife in the world!

Her prize-winning “Nature Photographer of the Year” photo is stunning.

Materials researchers have created a new composite material that combines two incompatible properties: stiff yet with a high damping capacity.