New Origami-inspired Design Turns Pushing Into Pulling

By Korey Haynes | May 24, 2019 4:46 pm
paper cells that collapse when pushed
The series of paper cells developed by researchers at the University of Washington uses origami folds to absorb the force of impacts. (Credit: Kiyomi Taguchi/University of Washington)

Whether applied to auto collisions or rocket landings, absorbing energy from impacts is a valuable trait, and industries have been working on various solutions for years. For spacecraft, landing safely has entailed everything from inflatable airbag systems to sky cranes to retro-thrusters. But what if the force of impact never made it to the spacecraft at all?

That’s the idea being pursued by Hiromi Yasuda and colleagues at the University of Washington. They’re using foldable materials inspired by origami to not only absorb the shock of impact, but actually change it into a force that travels back in the opposite direction. While the prototypes are made out of paper, the researchers say that many different materials could be used, possibly changing how rockets land in the future.

The researchers publishing their findings Thursday in Science Advances.

Fold the Force Away

Yasuda’s team came up with a unique cell that twists and folds, absorbing the force of an impact. They then connected 20 of the cells into a column, and glued caps onto each cell. (Glue is generally discouraged in more traditional origami art, but in engineering labs, it’s apparently okay.) The team filmed the finished product as it was compressed from one end, sending a wave of compression through each of the cells.

Tracing the wave, the researchers found that the complex array of folds stacked on top of each other actually managed to turn the pushing force from the compression into a pulling force.

“If you were wearing a football helmet made of this material and something hit the helmet,” said Jinkyu Yang, a co-author on the paper, “You’d never feel that hit on your head. By the time the energy reaches you, it’s no longer pushing. It’s pulling.”

The applications of such a material are nearly endless. Landers on the moon, where there is no atmosphere, must rely on retro rockets today, adding to fuel payloads. SpaceX’s Falcon 9 boosters already use a similar technology, a “crush core” in their landing gear made of an aluminum honeycomb structure which can absorb energy on impact. Unlike those crush cores, though, this design would likely be re-usable. And the potential benefits extend beyond space to the auto industry and more.

And if any school children are trying to drop an egg off a building, they might try their hand at origami.

CATEGORIZED UNDER: Space & Physics, top posts
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Reading Mars’ Deep Climate History in the Layers of its Ice Cap

By Korey Haynes | May 24, 2019 11:06 am
ice caps on mars
Radar reveals that Mars is hiding past ice caps under the ones visible today. (Credit: SA/DLR/FU Berlin; NASA MGS MOLA Science Team)

Bands of ice and sand at Mars’ north pole reveal an ancient climate that swung between warm and cold.

Mars, now dry and dusty, still holds water ice at its poles, and evidence strongly suggests it was once a planet where water flowed freely across the surface.

The Mars Reconnaissance Orbiter’s Shallow Radar (SHARAD) has peered deep into the northern ice cap and found layers of ice and sand buried beneath. The find adds nuance to the planet’s climate history, and reveals why some of the planet’s water remains locked in ice, instead of being lost to space.

Under the Ice

Mars’ north polar region includes a site called the cavi unit, made up of ice and sand, buried underneath the more visible northern ice cap. SHARAD can peer up to a mile and a half into the ice, imaging the different layers. What it saw were alternating layers of sand and ice.

Researchers know that Mars, like Earth, wobbles on its orbit over tens of thousands of years. And as it wobbles, tilting toward or away from the sun, the climate “wobbles” as well, growing warmer and cooler. So researchers think the ice in the cavi unit was laid down during colder, glacial periods on Mars. Previously, planetary scientists had assumed the ice would melt away during Mars’ warmer periods. But SHARAD revealed that the ice was instead covered over by sand, which insulated it from the sun’s warm rays. This prevented it from melting away or being lost entirely, as much of Mars’ surface water was when its atmosphere thinned away.

layers in alternating shades of blue
In some areas on Mars, layers of ice and sand are readily visible. Here the ice shows as light colors with the sand as darker shades of blue. (Credit: NASA/JPL/University of Arizona)

Altogether the ice contained in the layers is one of the largest water reservoirs scientists have identified on the Red Planet, coming in just behind the ice caps themselves. If melted, the water contained in the subsurface layers could cover the planet to a depth of about five feet.

The research was led by Stefano Nerozzi from the University of Texas, who published his findings in Geophysical Research Letters on May 22. An additional study, published the same day, led by researchers from Johns Hopkins University, uses gravitational measurements, instead of radar, to confirm the findings.

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Throughout the Ocean, Climate Change is Forcing Plankton to Move

By Roni Dengler | May 23, 2019 5:03 pm
plankton
(Credit: Choksawatdikorn/Shutterstock)

Some of the smallest creatures in the sea are also some of the most influential. Plankton, a group of microscopic marine organisms that includes bacteria, amoebas and snail larvae, among other things, prop up the base of the oceanic food chain. Every sea creature, from clownfish to whales, ultimately depend on plankton for food.

Now, a new study that peers into a past before human influence shows climate change has upset the distribution of plankton across the globe. The finding has implications that could ripple up to affect nearly all of marine life the researchers say.

Pre-Industrial Past

Most studies that look at how climate change is impacting the oceans show rising temperatures are forcing marine life to change where they live. But the majority of these studies use data collected only after World War II. This means they lack a pre-industrial baseline for comparison, said Lukas Jonkers, a paleoceanographer at the University of Bremen in Germany, who led the new research. To find this baseline, Jonkers examined plankton fossils from foraminifera buried in the seafloor.

Foraminifera are single-celled zooplankton. The animals come in a huge variety of shapes — stars, twisting cones, coils that resemble snail shells and circular blobs. But they all have a hard outer shell. Once buried in the seafloor, the shells remain well preserved. By examining these fossils, scientists can tell what plankton communities looked like before climate change affected ocean temperatures. 

Jonkers and colleagues assessed more than 3,000 foraminifera communities from sediment samples that chronicled hundreds or thousands of years of seafloor history.. The samples encompassed ecological regions and water temperatures from across the globe. The scientists then compared the pre-industrial plankton fossils to modern plankton communities that they caught in moored, funnel-shaped traps.

Changed Communities

The investigation revealed the species that make up modern foraminifera communities differ from their pre-industrial counterparts everywhere in the world, Jonkers said.

“I never expected the results to be so clear,” he said.

The plankton had shifted toward the poles, with a median distance of over 350 miles, though the distance differed greatly between communities. What’s more, past and present foraminifera communities were most different from each other where temperatures had changed the most, the researchers report Wednesday in the journal Nature.

“What this means is that in general plankton species have shifted … to such a degree that their distribution is now systematically different from before significant human influence,” Jonkers said.

Plankton are the foundation of the food supply in the oceans. Every marine organism, including the shrimp, crabs, lobsters and fish we eat, depends on plankton communities. The new findings raise questions about how marine ecosystems will respond to the changing conditions. 

“Species all shift range at difference paces and they now need to build new interaction networks, within species, but also with their new environment,” Jonkers said. “But at the moment, we don’t know if they can adapt fast enough to ongoing climate change.”

CATEGORIZED UNDER: Environment, Living World, top posts

NASA Announces Contractor for First Component of Lunar Gateway

By Korey Haynes | May 23, 2019 4:29 pm
illustration of a propulsion system with Earth in background
The power and propulsion system for the Lunar Gateway will be built by Maxar. Courtesy of Business Wire)

In a talk at the Florida Institute of Technology on Thursday, NASA administrator Jim Bridenstine announced that Maxar Technologies will build the first stage of NASA’s planned Lunar Gateway.

The Gateway, part of NASA’s larger Artemis program to return to the moon, is meant to be a waystation of sorts placed in a long orbit around the moon. It will provide a habitat for astronauts while they prepare to embark on longer missions, including moon landings, and serve as a place to assemble the components of rockets and other equipment in space.

The first element to be built and tested is a propulsion system, to move it between orbits and make sure it doesn’t drift away. Maxar (a new company formed from several veteran space industry players) is being awarded up to $375 million to build the system, which will convert solar power to electrical energy to power the Gateway, as well as provide propulsion, communication, and docking capabilities.

Getting the first stage of the Lunar Gateway into place is an important pre-requisite for NASA’s plans to land humans on the moon by 2024.  

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Why Scientists Are Putting a Telescope on the Bottom of the Ocean

By Korey Haynes | May 23, 2019 2:38 pm
lines of detectors linked by cables
The telescope, once complete, will be made of hundreds of spherical detectors suspended at the bottom of the sea. (Credit: KM3NeT)

Deep under the Mediterranean Sea, hundreds of watchful eyes hang suspended on cables, waiting for a rare and valuable flash. Their quarry are ghostly neutrino particles, capable of tunneling through light-years of space and a planet’s worth of rock without ever coming into contact with matter.

But, here, under the ocean, they just might hit a detector from the Cubic Kilometre Neutrino Telescope, or KM3NeT. While the international collaboration is still in the early stages of construction, it hopes to soon begin tracking some of the most elusive particles in the universe.

Neutrinos are nearly massless particles produced in the sun and in energetic events like supernovas, colliding stars, and gamma-ray bursts. Because the particles barely interact with the rest of the universe, they are notoriously difficult to study, though trillions pass through your body every second.

Researchers have tended to bury neutrino detectors in vats of supercooled liquids or miles underground, hoping that neutrinos will be the only particles that make it through.

This time, researchers are hiding the detectors at the bottom of the sea, on the other side of the planet from the skies they hope to study, to block everything but neutrinos from hitting their detectors.

Hidden Detectors

Most neutrino detectors look for the rare flashes of energy the particles give off when they collide with the nuclei of atoms. But because these interactions don’t happen very often, neutrino detectors have to cover a lot of ground – quite literally. KM3Net, as its name implies, will one day occupy a cubic kilometer of seawater – about 400,000 Olympic swimming pools worth.

Neutrino detectors also have to be protected from the onslaught of regular radiation, which would otherwise drown out the fainter gleam of neutrino interactions. So researchers build them deep underground, in abandoned mines or underneath Antarctic ice sheets.

Now, they are trying one at the bottom of the sea – and the other side of the world. “The underwater telescope is bombarded by millions of different particles but only neutrinos can pass through the Earth to reach the detector from below,” said Clancy James, a researcher at the Curtin Institute of Radio Astronomy in Australia, a KM3Net partner, in a statement. “So, unlike normal telescopes, it looks down through the Earth at the same sky viewed by upward-facing telescopes in Australia.”

Each telescope is actually made up of hundreds of spherical detectors a little bigger than a basketball. These are suspended on vertical lines, and each node is connected by cables that run along the sea floor. The first test components were installed in 2013, with another round of construction in 2015 and 2018. Scientists are currently testing a limited number of detectors, and they are still searching for funding to make the full array a reality.

Two telescopes comprise KM3Net. One is called ARCA, or Astroparticle Research with Cosmics in the Abyss, and it sits off the coast of Italy. It will study the higher-energy cosmic neutrinos produced by the universe’s most energetic events, like gamma-ray bursts, and provide scientists with a greater understanding of powerful astrophysical events. Its partner is ORCA, or Oscillation Research with Cosmics in the Abyss, located closer to France. This telescope will study the lower-energy particles produced by cosmic rays striking Earth’s atmosphere.

sphere with camera eyes
The detector spheres are each a little larger than a basketball. (Credit: KM3NeT)

So far, the telescope’s operations have been for testing purposes, proving that the setup is successful using only a few of the eventual hundreds of detectors. The team is in the process of adding more. The completion of the telescopes will mean that astronomers don’t have to get very, very lucky to spot a neutrino signal. Instead, the large array should open new windows into the hard-to-view world of barely-there particles.

CATEGORIZED UNDER: Space & Physics, top posts
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Room Temperatures Set for Men’s Comfort May Disadvantage Women, Study Finds

By Megan Schmidt | May 23, 2019 6:00 am
woman cold at work
Researchers say women are worse at math and word-based tasks at cooler room temperatures. (Credit: ESB Professional/Shutterstock)

“The women’s winter is here. The freeze is upon us,” warns a Game of Thrones parody about men and women’s office temperature preferences.

If you have a Y chromosome, you probably haven’t experienced “women’s winter.” As the video explains, women’s winter is “when spring turns to summer and there’s blossom on the trees, the office air doth turns to ice and all the women freeze.”

Although the skit is now a few years old, it perfectly captures women’s daily struggle with overly air-conditioned workplaces. To some people, thermostat complaints might seem trivial. But a new study has found that cold offices do more than make women shiver. Thermostat settings geared for men’s comfort — typically cooler temperatures — may actually disadvantage women by lowering their ability to perform some tasks.  

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CATEGORIZED UNDER: Mind & Brain, top posts

Bipolar Disorder Increases Parkinson’s Risk Sevenfold

By Anna Groves | May 22, 2019 5:00 pm
Woman With Parkinson's Disease
(Credit: Photographee.eu/Shutterstock)

Bipolar patients are seven times more likely to develop Parkinson’s disease, according to a new study. Though the news may be disheartening to those suffering from the already-trying condition, the link might also lead to clues about the causes behind the two conditions.

Parkinson’s is a complex disease associated with a gradual decline in dopamine levels produced by neurons, or brain cells. It eventually leads to impaired movements and other bodily functions. The causes are unknown, and there is no cure.

Bipolar disorder, also known as manic-depressive illness, is characterized by episodic fluctuations in mood, concentration or energy levels. Its causes are also unknown, though some bipolar-associated genes have been identified. Researchers are still figuring out how brain structure and function changes under the disease.

Previous research has linked Parkinson’s with depression. So when the authors of the new study, most of whom are practicing physicians, noticed some of their bipolar patients developing Parkinson’s, they wondered if there was a connection.

Seven Times The Risk

The study, out today in Neurology, was led by Huang Mao-Hsuan, who practices in the department of psychiatry at Taipei Veterans General Hospital. The researchers compared data from two groups of adults in the Taiwan National Health Insurance Research Database. Members of one group — over 56,000 individuals — were diagnosed with bipolar disorder between 2001 and 2009. The other — 225,000 individuals — had never been diagnosed with the disorder. No one in either cohort had received a Parkinson’s diagnosis and all the patients were over 20. And researchers ensured the two groups had similar ages, socioeconomic status, and other traits that might influence health.

The researchers followed up with all 278,000 people in 2011 to see how many had been subsequently diagnosed with Parkinson’s. They found that 0.7 percent of the patients with bipolar disorder ended up developing the disease — about 1 in 140. But for those without the disorder, the prevalence of Parkinson’s was about 1 in 1,000, or 0.1 percent.

Link Uncertain

Researchers found the trend held even when controlling for the potential effects of antipsychotic medications, which are frequently prescribed for bipolar disorder and are known to cause Parkinson’s-like symptoms (known as drug-induced parkinsonism, or DIP.)

The only clue to a mechanism that would explain the link was that patients with the highest frequency of psychiatric admission for bipolar episodes also had the highest prevalence of Parkinson’s. It’s not clear why this would be, though both bipolar disorder and Parkinson’s are known to be linked to impaired dopamine transmission in the brain. More research is needed to figure out what the connection between these two diseases might be.

Rare Meteorite Fall in Costa Rica Could Shed Light on Earth’s Water

By Korey Haynes | May 22, 2019 12:04 pm
rock held in hand
One of the meteorites that fell at Aguas Zarcas struck a doghouse’s roof. (Photo courtesy of Michael Farmer)

A rare meteorite fall in Costa Rica has astronomers racing to get their hands on samples.

Meteorites are an astronomer’s dream. In a field that by definition studies objects and phenomena above and beyond Earth’s atmosphere, many researchers never get a chance to touch or see up close the things they study. But then, sometimes, these items simply rain down from the sky, in the form of ancient space rocks called meteorites.

Meteorites come in many different types. But some of the most precious are called carbonaceous chondrites, valued because they contain large amounts of water and organic compounds. These meteorites contain a history of that water from the solar system’s early days, and trace how the materials of life were distributed across the planets and space.

On April 23 of this year, one of these meteors – roughly the size of a washing machine – streaked through the skies over the Costa Rican town of Aguas Zarcas. As it fell, it broke into many smaller pieces, and astronomers scrambled to collect and study them. They are the first large fall of carbonaceous chondrites in half a century, and should provide ample data on the history of water in the solar system, according to a press release from Arizona State University, which is studying the meteorite.

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CATEGORIZED UNDER: Space & Physics, top posts

Baby Tiger Sharks Are Eating Sparrows And Woodpeckers

By Roni Dengler | May 21, 2019 5:03 pm
tiger shark
A tiger shark — woodpeckers beware. (Credit: Shane Gross/Shutterstock)

Often called “the garbage cans of the sea,” tiger sharks are voracious eaters. The sharks will eat just about anything — fish, other sharks, seabirds, sea turtles, whale carcasses. The list goes on.

That hodgepodge of prey now also includes a few creatures that don’t usually even go in the ocean. Young tiger sharks also feast on sparrows, woodpeckers and other land-based birds, says a group of researchers. The adolescent sharks are probably dining on songbirds in order to fill their bellies as they work to improve their hunting skills, they say.

“While tiger sharks are known to consume birds, we were surprised to see that all the birds we identified were terrestrial,” said Marcus Drymon, a marine fisheries expert at Mississippi State University in Biloxi, who led the new research.

Feathery Surprise

Drymon and colleagues have been keeping tabs on tiger shark populations along the Mississippi and Alabama coasts for nearly a decade. As part of a routine monitoring survey in 2010, Drymon captured a small tiger shark to tag and release. When the researchers made the shark throw up to see what it had been eating, feathers came out. DNA analysis revealed they belonged to a brown thrasher, a highly musical songbird about the size of a robin that usually calls scrubby fields and dense woods home.

gathering tiger shark stomach contents
Scientists gathering stomach contents from a baby tiger shark. (Credit: Marcus Drymon)

Over the next eight years, Drymon and colleagues examined the stomach contents of more than 100 tiger sharks looking for feathers, beaks, feet and other bird remains. More than a third of the tiger sharks’ stomachs had bird remnants, the researchers report Tuesday in the journal Ecology.

Drymon sent the remains to Marcus Feldheim, a molecular systematics researcher at the Field Museum in Chicago, for DNA analysis and identification. Feldheim identified 11 bird species in the sharks’ stomach contents. In a major surprise, none of the remains belonged to a seabird.

“I assumed the DNA would tell us they belonged to things like gulls or pelicans, not species like house wrens, doves, and sapsuckers,” Feldheim said.

Birds on the Stomach

The researchers found most of the fatal bird-shark run-ins happened in the fall, when birds migrating south take a final break along the coast before making the long journey across the Gulf of Mexico. The birds time their departure to make the best use of southward winds. But bad weather can force the birds toward the surface of the water, making them sitting ducks (and sparrows and woodpeckers) for sharks, especially baby ones.

The bird migrations happen to coincide with tiger shark births in the Gulf of Mexico. Nearly half of the sharks with avian remains in their stomachs were newborn sharks, the team found. The finding suggests baby tiger sharks take advantage of the easy and abundant prey.

“It appears that newborn tiger sharks in the northern Gulf of Mexico routinely scavenge songbirds before they’ve developed adult hunting behaviors,” Drymon said.

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals

Our Moon May Have Been Hit By a Dwarf Planet Long Ago

By Korey Haynes | May 21, 2019 4:39 pm
moon far side
The moon’s far side, as photographed by the Lunar Reconnaissance Orbiter (LRO) (Credit: NASA/GSFC/Arizona State University)

The familiar lunar vista humans see when they look up at night reveals a face with dark “seas” and bright craters. The mysterious far side, which wasn’t revealed until humans started sending probes and then people in the 1960s, is far more heavily cratered, with few of the dark plains of the near side.

But what caused the two sides to be so different? That’s been a matter of debate.

Now, researchers led by Meng-Hua Zhu, from the Macau University of Science and Technology, say that a dwarf planet striking the moon sometime after its initial formation could have caused the lopsided world we see today. They published their research May 20 in the Journal of Geophysical Research: Planets.

A Series of Planet-sized Collisions

The standard story of the moon’s formation is that sometime in Earth’s early history, a planet-sized body struck our planet, throwing material high into space, where it eventually coalesced into the moon we see today. But even this dramatic tale can’t explain all the oddities of Earth’s moon, like the difference between the moon’s near and far sides.

A clue came in 2012, when NASA’s GRAIL mission showed that the lunar near side has a thinner crust than the far side.

So over the years, as both sides suffered numerous asteroid strikes, the near side cracked open. The outpouring lava filled basins and hardened into the dark maria, or plains, we see today. But the far side has a thicker crust, so there’s just a lot of cratering. But the puzzle of why the two hemispheres have different thicknesses to begin with is harder to explain.

One way to solve the problem is if a small world – about the size of the dwarf planet Ceres, which resides in the asteroid belt – were to have hit the moon’s near side after it had already formed and solidified. The impact would have thrown up material, and when the material resettled, it could have fallen mainly on the far side of the moon, burying it under 3 to 6 miles of lunar regolith. Zhu and colleagues ran a series of computer simulations to test this scenario, and found that an object ramming the early moon at between 14,000 and 15,000 miles per hour would recreate the moon as we see it today. That may sound fast, but it’s only about a quarter the speed of most small meteors that hit Earth.

The impact could also help clear up some of the long-standing questions about the materials that make up the moon. They are both very Earth-like in some ways – a sign that the moon did indeed form out of Earth debris – and dissimilar in other ways, pointing to additions from an outside world.

That would make our moon a composite of three different large bodies — a different sort of three-body problem.

CATEGORIZED UNDER: Space & Physics, top posts
MORE ABOUT: moon
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