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Science

Unexpected Solar Wind Stream Hits Earth at 372 Miles Per Second

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On Sunday, Earth’s magnetic field was pelted by a solar wind stream reaching velocities of more than 600 kilometers (372 miles) per second.

While that’s nothing too alarming – solar storms often pummel our planet triggering spectacular auroras – what is weird is that this storm was totally unexpected.

 

“This event was not in the forecast, so the resulting auroras came as a surprise,” SpaceWeather reported. 

Solar wind occurs when a stream of highly energized particles and plasma can no longer be held back by the Sun’s gravity and burst out towards Earth.

There’s a lot we still don’t know about how our Sun works, but these emissions are thought to come from large bright patches on the Sun known as ‘coronal holes’ and scientists do a great job of monitoring them from here on Earth. 

Through this monitoring, they’re able to create space weather ‘forecasts’ that not only predict when solar storms or solar flares, also known as coronal mass ejections (CMEs), are heading our way, but how powerful they’ll be.

But that doesn’t mean we can’t still get surprised like we did over the weekend. 

Early on Sunday, NASA’s Deep Space Climate Observatory (DSCOVR) noticed light solar wind streams, which increased significantly and unexpectedly throughout the day.

The cause of this solar storm is still unknown, but SpaceWeather speculates it could have been the early arrival of solar wind expected to come from an equatorial hole in the Sun’s atmosphere two days later.

 

Or it could have been a missed coronal mass ejection (CME).

“A discontinuity in solar wind data at 0045 UT on Aug. 7th hints at a shock wave embedded in the solar wind,” writes Space Weather.

“These days, the active sun is producing so many minor explosions, it is easy to overlook faint CMEs heading for Earth.”

At the time of writing, the high-velocity solar wind continues to slam into Earth’s magnetic field, with records showing the speed is reaching 551.3 kilometers (343 miles) per second as of August 9, 0406 UTC (0006 ET).

The good news is that solar wind isn’t damaging to us here on Earth, safely protected by our planet’s atmosphere. 

When it’s strong, though, it can impact our technologies, causing issues with telecommunication satellites and, in extreme cases, power grids.

These winds were classified as a moderate G2 solar storm – storms are ranked G1 at the lowest end of the scale all the way up to G5, which is a powerful solar storm.

G2 storms can affect high latitude power systems and could impact the orbit predictions of spacecraft, according to Space Weather. 

 

If you feel like this all sounds familiar, that’s because we’ve witnessed a lot of solar storms this year, with the Sun now in the active phase of its 11-year solar cycle.

Already this year we’ve been hit by X-class flares and giant coronal holes, more than 2.5 times Earth’s size. Most of the time you’d have no idea this was happening.

Unless you’re an avid aurora watcher, that is.

Fortunately, followers of the Space Weather Alert Service were notified about the unforecast storm and were able to make it out to see the resulting powerful auroras and Steve, which were seen as far south as Pennsylvania.

“I was already in bed getting ready for sleep when the storm began,” astrophotographer Ruslan Merzlyakov told Space Weather.

“Rushing to the beach in Nykøbing Mors, I was able to photograph the first summer auroras in Denmark in 5 years.”

Who knows what the rest of the week may have in store for us.

 

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Science

The Universe Could ‘Bounce’ For Eternity. But It Still Had to Start Somewhere

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From the smallest bacterium to the greatest galaxy, death looms on the horizon; even if, in cosmic terms, the time scales are too large for us to truly comprehend. Eventually, even the Universe itself should come to an end – when the last light winks out, and the cold, dense lumps of dead stars are all that remain.

 

That is, at least, how it is under current cosmological models. What if our Universe doesn’t die a cold death, but collapses, reinflates, and collapses again, over and over, like a giant cosmic lung?

It’s not exactly a widely accepted theory, but for some cosmologists, our Universe could be just one in a long series of births, deaths and rebirths that is without beginning or end – not a Big Bang, but a Big Bounce.

Now physicists have shown that the latest iteration of the Big Bounce hypothesis – which had solved significant problems with previous iterations – still has pretty major limitations.

“People proposed bouncing universes to make the Universe infinite into the past, but what we show is that one of the newest types of these models doesn’t work,” said physicist Will Kinney of the University at Buffalo.

“In this new type of model, which addresses problems with entropy, even if the Universe has cycles, it still has to have a beginning.”

Currently, the most accepted model of our Universe sees it emerge from a point of origin called a singularity. Around 13.8 billion years ago the Universe as we know it began to expand out of an impossibly dense bit of time and space … for some reason.

 

Unfortunately the models supporting a ‘Big Bang’ explanation have little to say much about what such a singularity might look like. 

The Big Bounce hypothesis, as an alternative, could sidestep the issue of a singularity by doing away with it entirely. A collapsing universe would instead rebound before it ever reached such a model-breaking moment.

The hypothesis hasn’t been without its own issues, however. An endlessly “bouncing” Universe should also have endlessly growing entropy, the measure of disorder in the Universe. If the Big Bang was just one of an eternal series of bangs, the entropy should therefore have been really high; yet it wasn’t. In fact, if the Universe was high in entropy at the Big Bang, it couldn’t exist as we know it.

In 2019, the Big Bounce got a reprieve, with the publication of a revised model that contained a solution to this significant hurdle that had stymied the hypothesis for decades. Researchers found that the expansion of the Universe with each cycle dilutes entropy sufficiently to return the Universe to its original state before the next bounce.

 

This was a huge deal, seemingly putting the Big Bounce back on the table as a plausible cosmological model; but now, other scientists have done what scientists do best. They have poked a new hole in the revised model.

Kinney and his colleague, physicist Nina Stein, also of the University at Buffalo, conducted a series of calculations, and found that a cyclic Universe can’t stretch endlessly back into the past.

“Long story short, we showed that in solving the entropy problem, you create a situation where the Universe had to have a beginning,” Kinney explained. “Our proof shows in general that any cyclic model which removes entropy by expansion must have a beginning.”

That doesn’t mean that the cyclic Universe is dead in the water. The team notes that their work does not apply to physicist Roger Penrose’s model of the cyclic Universe, called conformal cyclic cosmology. According to his version of a repeating universe, each cycle expands infinitely with no period of contraction. That is pretty complex stuff, and is going to require further poking.

For now, however, it seems that the Big Bounce is, at the very least, going to require a bit more thought to remain viable.

“The idea that there was a point in time before which there was nothing, no time, bothers us, and we want to know what there was before that – scientists included,” Stein said. “But as far as we can tell, there must have been a ‘beginning’. There is a point for which there is no answer to the question, ‘What came before that?'”

The research has been published in the Journal of Cosmology and Astroparticle Physics.

 

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Science

These Dwarf Galaxies Seem to Be Devoid of Dark Matter, And It Doesn’t Make Sense

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Ask astronomers about dark matter and one of the things they talk about is that this invisible, mysterious ‘stuff’ permeates the universe. In particular, it exists in halos surrounding most galaxies.

 

The mass of the halo exerts a strong gravitational influence on the galaxy itself, as well as on others in the neighborhood. That’s pretty much the standard view of dark matter and its influence on galaxies.

However, there are problems with the idea of those halos. Apparently, some oddly shaped dwarf galaxies exist that look like they have no halos. How could this be? Do they represent an observationally induced challenge to the prevailing ideas about dark matter halos?

Finding Perturbed Dwarf Galaxies

In the so-called “Standard Model” of cosmology, shells or halos of dark matter protect galaxies from the gravitational influence of nearby galactic neighbors.

However, when astronomers at the University of Bonn and Saint Andrews in Scotland looked in the nearby Fornax Cluster, which lies some 62 million light-years away from us, they saw something strange.

It contains a number of dwarf galaxies with distorted, perturbed shapes. This is odd, especially if they should be surrounded by dark matter halos.

The Fornax Galaxy Cluster. (ESO/J. Emerson/VISTA)

Let’s take a quick look at dwarf galaxies. They’re small and faint and usually found riding along in galaxy clusters or near much larger companions. The Milky Way Galaxy has a coterie of dwarf galaxies around it.

It is, in fact, cannibalizing ones such as the Sagittarius Dwarf Spheroidal. Interestingly, recent studies show that at least one of the dwarf galaxies near ours, an ancient one called Tucana II, has an astoundingly massive dark matter halo.

 

So, what’s happening in Fornax that’s different?

There, dwarf galaxies could be “disturbed” by gravitational tides from nearby larger ones in the cluster. Tides happen when gravity from one body pulls differently on different parts of another body. These are similar to tides on Earth when the Moon pulls more strongly on the side of Earth that faces it.

The distorted shapes of the dwarf galaxies seen by the team indicate a problem with our understanding of dark matter.

“Such perturbations in the Fornax dwarfs are not expected according to the Standard Model,” said Pavel Kroupa, Professor at the University of Bonn and Charles University in Prague.

“This is because, according to that model, the dark matter halos of these dwarfs should partly shield them from tides raised by the cluster.”

Explaining Distorted Dwarf Galaxies

Kroupa and Ph.D. student Elena Ascencio analyzed observations of the perturbed dwarfs in Fornax. They wanted to understand the extent of gravitational distortions these galaxies show and what causes them.

The expected levels of distortion depend on a couple of factors. One is the internal characteristics of the dwarf galaxy. In addition, their distance to the center of the cluster is important. That’s where gravitational influences are much stronger.

 

As a rule, galaxies with large sizes but not many stars could be easily disturbed by strong gravitational tides. The same is true for galaxies closer to the core of the cluster.

The team members compared what they saw in the cluster with observations made by the VLT Survey Telescope at the European Southern Observatory. Asencio pointed out that what they found seems to point to problems with the Standard Model.

“The comparison showed that, if one wants to explain the observations in the standard model,” she said, “the Fornax dwarfs should already be destroyed by gravity from the cluster center even when the tides it raises on a dwarf are sixty-four times weaker than the dwarf’s own self-gravity.”

Not only is this counter-intuitive, she said, it also contradicts previous studies. The team also found that the force needed to disturb a dwarf galaxy is about the same as its self-gravity.

What Does This Mean for the Standard Model?

The research team points out that it’s difficult to explain these perturbed, disturbed shapes of the dwarf galaxies in Fornax if they’re surrounded by dark matter. In other words, they shouldn’t be misshapen if they do have halos.

 

Yet, there they are with disturbed-looking shapes. That means that there are no dark matter halos around those galaxies.

Obviously, if what the astronomers found is confirmed, then the Standard Model needs some tweaking. And, there is at least one alternative explanation for the strange galaxy shapes. It’s called the MOND model (short for Modified Newtonian Dynamics).

It suggests that Newton’s law of universal gravitation should be modified to account for the observed properties of galaxies. It could be applied to explain why misshapen galaxies look the way they do.

According to Hongsheng Zhao, a member of the research team from the University of Saint Andrews, finding disturbed dwarfs without dark matter halos is a major challenge to the current view.

It states that galaxies have halos. It appears not all of them do, he points out.

“Our results have major implications for fundamental physics,” he said. “We expect to find more disturbed dwarfs in other clusters, a prediction which other teams should verify”.

This article was originally published by Universe Today. Read the original article.

 

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Science

Earth Just Had Its Shortest Day on Record, Thanks to a ‘Wobble’

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The Earth had its shortest ever day this summer, thanks to a wobble in its axis which meant it completed a single spin in a fraction of a second less than 24 hours.

June 29 was 1.59 milliseconds shorter than 86,400 seconds, or exactly 24 hours, according to the website timeanddate.com.

 

In recent decades the Earth has been more likely to slow down, giving marginally longer days. But in the last few years, that tendency reversed, and the days have been getting shorter and shorter.

If the Earth continues to speed up, this could lead to the first-ever requirement to subtract a second from atomic clocks.

The Earth is not perfect

It’s not uncommon for the Earth to wobble – the spinning which we experience as night and day does not always happen exactly in line with its axis, the line between the North and South Poles.

That’s because it is not a precise sphere.

The planet has a bulge at the equator, while the poles are slightly squashed, meaning Earth is slightly elliptical.  

Other factors can mess with the spinning too, including ocean tides and gravity from the Moon.

The “Chandler wobble”

Leonid Zotov, a professor of mathematics, believes that the Earth may be spinning faster because of a periodic movement called the “Chandler wobble”. 

The wobble was first spotted in the late 1880s, when astronomer Seth Carlo Chandler noticed the poles wobbled over a period of 14 months.

 

This wobble started to slow down in early 2000s, reaching historic minimums since 2017, per The Telegraph. 

And between 2017 to 2020, “it disappeared”, Zotov told timeanddate.com.

Zotov is due to present this hypothesis at the Asia Oceania Geosciences Society, per timeanddate.com. It has not yet been peer-reviewed.

Earth wobbles don’t change much in day-to-day life. But they are important to keep track of, so the atomic clock can remain accurate to precisely coordinate GPS and Earth-observing satellites.

This article was originally published by Business Insider.

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Science

This Record-Breaking ‘Black Widow’ Pulsar Is The Most Massive Neutron Star Yet

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One of the most extreme stars in the Milky Way just got even more wack.

Scientists have measured the mass of a neutron star named PSR J0952-0607, and found that it’s the most massive neutron star discovered yet, clocking in at a whopping 2.35 times the mass of the Sun.

 

If true, this is very close to the theorized upper mass limit of around 2.3 solar masses for neutron stars, representing an excellent laboratory for studying these ultra-dense stars at what we think is the brink of collapse, in the hope of better understanding the weird quantum state of the matter of which they are made.

“We know roughly how matter behaves at nuclear densities, like in the nucleus of a uranium atom,” said astrophysicist Alex Filippenko of the University of California, Berkeley.

“A neutron star is like one giant nucleus, but when you have one-and-a-half solar masses of this stuff, which is about 500,000 Earth masses of nuclei all clinging together, it’s not at all clear how they will behave.”

Neutron stars are the collapsed cores of massive stars that were between around 8 and 30 times the mass of the Sun, before they went supernova and blew most of their mass off into space.

These cores, tending to be around 1.5 times the mass of the Sun, are among the densest objects in the Universe; the only thing denser is a black hole.

 

Their mass is packed into a sphere just 20 kilometers (12 miles) or so across; at that density, protons and electrons can combine into neutrons. The only thing keeping this ball of neutrons from collapsing into a black hole is the force it would take for them to occupy the same quantum states, described as degeneracy pressure.

In some ways this means neutron stars behave like massive atomic nuclei. But what happens at this tipping point, where neutrons form exotic structures or blur into a soup of smaller particles, is hard to say.

PSR J0952-0607 was already one of the most interesting neutron stars in the Milky Way. It’s what is known as a pulsar – a neutron star that is spinning very fast, with jets of radiation emitting from the poles. As the star spins, these poles sweep past the observer (us) in the manner of a cosmic lighthouse so that the star appears to pulse.

These stars can be insanely fast, their rotation rate on millisecond scales. PSR J0952-0607 is the second-fastest pulsar in the Milky Way, rotating a mind-blowing 707 times per second. (The fastest is only slightly faster, with a rotation rate of 716 times per second.)

 

It’s also what is known as a “black widow” pulsar. The star is in a close orbit with a binary companion – so close that its immense gravitational field pulls material from the companion star. This material forms an accretion disk that whirls around and feeds into the neutron star, a bit like water swirling around a drain. Angular momentum from the accretion disk is transferred to the star, causing its spin rate to increase.

A team led by astrophysicist Roger Romani of Stanford University wanted to understand better how PSR J0952-0607 fit into the timeline of this process. The binary companion star is tiny, less than 10 percent of the mass of the Sun. The research team made careful studies of the system and its orbit and used that information to obtain a new, precise measurement for the pulsar.

Their calculations returned a result of 2.35 times the mass of the Sun, give or take 0.17 solar masses. Assuming a standard neutron star starting mass of around 1.4 times the mass of the Sun, that means that PSR J0952-0607 has slurped up to an entire Sun’s worth of matter from its binary companion. This, the team says, is really important information to have about neutron stars.

“This provides some of the strongest constraints on the property of matter at several times the density seen in atomic nuclei. Indeed, many otherwise popular models of dense-matter physics are excluded by this result,” Romani explained.

“A high maximum mass for neutron stars suggests that it is a mixture of nuclei and their dissolved up and down quarks all the way to the core. This excludes many proposed states of matter, especially those with exotic interior composition.”

The binary also shows a mechanism whereby isolated pulsars, without binary companions, can have millisecond rotation rates. J0952-0607’s companion is almost gone; once it’s entirely devoured, the pulsar (if it’s not tipped over the upper mass limit and collapses further into a black hole) will retain its insanely fast rotation speed for quite some time.

And it will be alone, just like those all the other isolated millisecond pulsars. 

“As the companion star evolves and starts becoming a red giant, material spills over to the neutron star, and that spins up the neutron star. By spinning up, it now becomes incredibly energized, and a wind of particles starts coming out from the neutron star. That wind then hits the donor star and starts stripping material off, and over time, the donor star’s mass decreases to that of a planet, and if even more time passes, it disappears altogether,” Filippenko said.

“So, that’s how lone millisecond pulsars could be formed. They weren’t all alone to begin with – they had to be in a binary pair – but they gradually evaporated away their companions, and now they’re solitary.”

The research has been published in The Astrophysical Journal Letters.

 

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Science

An ‘Impossible’ Quasicrystal Was Created in The World’s First Nuclear Bomb Test

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At 5:29 am on the morning of 16 July 1945, in the state of New Mexico, a dreadful slice of history was made.

The dawn calm was torn asunder as the United States Army detonated a plutonium implosion device known as the Gadget – the world’s very first test of a nuclear bomb, known as the Trinity test. This moment would change warfare forever.

 

The energy release, equivalent to 21 kilotons of TNT, vaporized the 30-meter test tower (98 ft) and miles of copper wires connecting it to recording equipment. The resulting fireball fused the tower and copper with the asphalt and desert sand below into green glass – a new mineral called trinitite.

Decades later, scientists discovered a secret hidden in a piece of that trinitite – a rare form of matter known as a quasicrystal, once thought to be impossible.

“Quasicrystals are formed in extreme environments that rarely exist on Earth,” geophysicist Terry Wallace of Los Alamos National Laboratory explained last year.

“They require a traumatic event with extreme shock, temperature, and pressure. We don’t typically see that, except in something as dramatic as a nuclear explosion.”

Most crystals, from the humble table salt to the toughest diamonds, obey the same rule: their atoms are arranged in a lattice structure that repeats in three-dimensional space. Quasicrystals break this rule – the pattern in which their atoms are arranged does not repeat.

When the concept first emerged in the scientific world in 1984, this was thought to be impossible: crystals were either ordered or disordered, with no in-between. Then they were actually found, both created in laboratory settings and in the wild – deep inside meteorites, forged by thermodynamic shock from events like a hypervelocity impact.

 

Knowing that extreme conditions are required to produce quasicrystals, a team of scientists led by geologist Luca Bindi of the University of Florence in Italy decided to take a closer look at trinitite.

But not the green stuff. Although they’re uncommon, we have seen enough quasicrystals to know that they tend to incorporate metals, so the team went looking for a much rarer form of the mineral – red trinitite, given its hue by the vaporized copper wires incorporated therein.

Using techniques such as scanning electron microscopy and X-ray diffraction, they analyzed six small samples of red trinitite. Finally, they got a hit in one of the samples – a tiny, 20-sided grain of silicon, copper, calcium and iron, with a five-fold rotational symmetry impossible in conventional crystals – an “unintended consequence” of warmongering.

“This quasicrystal is magnificent in its complexity – but nobody can yet tell us why it was formed in this way,” Wallace explained in 2021 when the team’s research was published.

“But someday, a scientist or engineer is going to figure that out and the scales will be lifted from our eyes and we will have a thermodynamic explanation for its creation. Then, I hope, we can use that knowledge to better understand nuclear explosions and ultimately lead to a more complete picture of what a nuclear test represents.”

 

This discovery represents the oldest known anthropogenic quasicrystal, and it suggests that there may be other natural pathways for the formation of quasicrystals. For example, the fulgurites of molten sand forged by lightning strikes, and material from meteor impact sites, could both be a source of quasicrystals in the wild.

The research could also help us better understand illicit nuclear tests, with the eventual aim of curbing the proliferation of nuclear armaments, the researchers said. Studying the minerals forged at other nuclear testing sites could uncover more quasicrystals, the thermodynamic properties of which could be a tool for nuclear forensics.

“Understanding other countries’ nuclear weapons requires that we have a clear understanding of their nuclear testing programs,” Wallace said.

“We typically analyze radioactive debris and gases to understand how the weapons were built or what materials they contained, but those signatures decay. A quasicrystal that is formed at the site of a nuclear blast can potentially tell us new types of information – and they’ll exist forever.”

The research has been published in PNAS.

 

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Health

Dietary Supplement Cuts Risk of Hereditary Cancer by 60%, Scientists Find

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A trial spanning more than 20 years and almost 1,000 participants worldwide has found an important result – people with a condition that gives them a higher chance of developing certain cancers can reduce the risk of some of those cancers by more than 60 percent, simply by adding more resistant starch to their diets.

 

In fact, the results were so compelling when it came to cutting the risk of upper gastrointestinal (GI) cancers specifically that the researchers are now looking to replicate them to ensure they’re not missing anything. 

“We found that resistant starch reduces a range of cancers by over 60 percent. The effect was most obvious in the upper part of the gut,” says lead researcher and nutritionist John Mathers from Newcastle University in the UK. 

Upper GI cancers include esophageal, gastric, and pancreatic cancers.

“The results are exciting, but the magnitude of the protective effect in the upper GI tract was unexpected, so further research is required to replicate these findings,” adds one of the researchers, Tim Bishop, a genetic epidemiologist from the University of Leeds. 

Resistant starch is a type of starch that passes through the small intestine and then ferments in the large intestine, where it feeds beneficial gut bacteria. It can be bought as a fiber-like supplement, and is naturally in a range of foods, including slightly green bananas, oats, cooked and cooled pasta and rice, peas, and beans. 

 

The double-blind trial was carried out between 1999 and 2005 and involved a group of 918 people with a condition known as Lynch syndrome. Lynch syndrome is one of the most common genetic predispositions to cancer that we know of, with around one in 300 people estimated to carry an associated gene.

Those who’ve inherited Lynch syndrome genes have a significantly increased risk of developing colorectal cancer, as well as gastric, endometrial, ovarian, pancreatic, prostate, urinary tract, kidney, bile duct, small bowel, and brain cancers. 

To figure out how they could reduce this risk, participants were randomly assigned to one of two groups, with 463 unknowingly given a daily 30 gram dose of resistant starch in powdered form for two years – roughly the equivalent of eating a not-quite-ripe banana daily. 

Another 455 people with Lynch syndrome took a daily placebo that looked like powdered starch but didn’t contain active ingredients.  

The two groups were then followed up 10 years later. The results of this follow-up are what the researchers have just published.

In the follow-up period, there had only been 5 new cases of upper gastrointestinal (GI) cancers among the 463 people who’d taken the resistant starch. This is in comparison with 21 cases of upper GI cancer among the 455 people in the placebo group – a pretty remarkable reduction. 

 

“This is important as cancers of the upper GI tract are difficult to diagnose and often are not caught early on,” says Mathers.

However, there was one area where the resistant starch didn’t make much difference – in the rate of bowel cancers.

Further work is needed to figure out exactly what’s going on here, but the team has some ideas.

“We think that resistant starch may reduce cancer development by changing the bacterial metabolism of bile acids and to reduce those types of bile acids that can damage our DNA and eventually cause cancer,” says Mathers.

“However, this needs further research.”

To be clear, this trial was carried out on people already genetically predisposed to developing cancer and doesn’t necessarily apply to the broader public. But there could be a lot to learn by better understanding how resistive starch can help protect against cancer.

The original trial was called the CAPP2 study, and the team are now carrying out a follow-up called CaPP3, involving more than 1,800 people with Lynch syndrome.

While it may sound concerning that the rate of colorectal cancers didn’t seem affected by the resistive starch, don’t worry, the study had good news on that front, too.

 

The original trial also looked at whether taking aspirin daily could reduce cancer risk. Back in 2020, the team published results showing that aspirin reduced the risk of large bowel cancers in Lynch syndrome patients by 50 percent.

“Patients with Lynch syndrome are high risk as they are more likely to develop cancers, so finding that aspirin can reduce the risk of large bowel cancers and resistant starch other cancers by half is vitally important,” says Newcastle University geneticist Sir John Burns who ran the trial with Mathers.

“Based on our trial, NICE [the UK’s National Institute for Health and Care Excellence] now recommend Aspirin for people at high genetic risk of cancer, the benefits are clear – aspirin and resistant starch work.”

The research has been published in Cancer Prevention Research.

 

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Science

Scientists Are Turning Dead Spiders Into ‘Necrobots’ And We Are So Creeped Out

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When mechanical engineering graduate student Faye Yap saw a dead spider curled up in the hallway, it got her thinking about whether it could be used as a robotics component. 

Turning dead spiders into mechanical grippers may be some people’s idea of a nightmare scenario, but it could have tangible benefits. Spider legs can grip large, delicate, and irregularly shaped objects firmly and softly without breaking them. 

 

So, in collaboration with mechanical engineer Daniel Preston, Yap and her colleagues at Rice University discovered a way to make a dead wolf spider’s legs unfurl and grip onto objects.

They called this new type of robotics ‘necrobotics’.

Weirdly, spider legs don’t have muscles for extension, but instead move their legs via hydraulic pressure – they have what’s called a prosoma chamber, or cephalothorax, which contracts, sending inner body fluid into their legs, making them extend.  

So, the team inserted a needle into the spider’s prosoma chamber and created a seal around the tip of the needle with a glob of superglue. Squeezing a tiny puff of air through the syringe was enough to activate the spider’s legs, achieving a full range of motion in less than one second. 

“We took the spider, we placed the needle in it not knowing what was going to happen,” says Yap in a video on the Rice University website.

“We had an estimate of where we wanted to place the needle. And when we did, it worked, the first time, right off the bat. I don’t even know how to describe it, that moment.”

 

The team were able to make the dead spider grip onto a small ball and used that experiment to determine a peak grip force of 0.35 millinewtons.

They then demonstrated the use of a dead spider to pick up delicate objects and electronics, including having this necrobotic gripper remove a jumper wire attached to an electric breadboard and then move a block of polyurethane foam.

They also showed that the spider could bear the weight of another spider of about the same size. 

(Preston Innovation Laboratory/Rice University)

Since spiders extend their legs by exerting hydraulic pressure from their cephalothorax, when they die the hydraulic system doesn’t work anymore. The flexor muscles in the spider’s legs go into rigor mortis, but, as the muscles only work in one direction, the spider curls up.

While most man-made robotics components are quite complex to manufacture, spiders are complex already and (unfortunately for arachnophobes) are in plentiful supply. 

“The concept of necrobotics proposed in this work takes advantage of unique designs created by nature that can be complicated or even impossible to replicate artificially,” the researchers say in their paper.

 

Spiders are also biodegradable, so using them as robot parts would cut the amount of waste in robotics. 

“One of the applications we could see this being used for is micro-manipulation, and that could include things like micro-electronic devices,” says Preston in the video. 

One drawback to the dead spider gripper is that it starts to experience some wear and tear after two days or after 1,000 open-and-close cycles.

“We think that’s related to issues with dehydration of the joints. We think we can overcome that by applying polymeric coatings,” explains Preston. 

The researchers experimented with coating the wolf spiders in beeswax and found that its mass decrease was 17 times less than the uncoated spider over 10 days, which meant it was retaining more water and its hydraulic system might function longer. 

This study was published in Advanced Science. 

 

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Science

This Horrifying Zombie Fungus Forces Males to Mate With The Dead. Now We Know How

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The fungus Entomophthora muscae has a survival strategy that’s both fascinating and potentially going to put you off your next meal: it infects and ‘zombifies’ female houseflies before sending out irresistible chemical signals encouraging male houseflies into necrophilia.

 

By luring these male flies into mating with zombified females, the fungus can transfer to the male fly and, in theory, have a better chance of further dispersal. The unlucky male fly is then taken over by E. muscae in the same way.

Crucial to the process is the release of sesquiterpenes, or chemical messages, which are synthesized in the female cadaver and sent out as a seductive signal. Based on the experiments carried out by the researchers, the longer the corpse has been dead, the more attractive it appears to be to the males.

“The chemical signals act as pheromones that bewitch male flies and cause an incredible urge for them to mate with lifeless female carcasses,” says evolutionary biologist Henrik H. De Fine Licht, from the University of Copenhagen in Denmark.

Once E. muscae has infected a female fly with its spores, it starts to multiply. After around six days, it can control the behavior of the insect, sending it up to the highest possible point (on a wall or a plant) before it dies. Fungus spores are then sent out from the dead fly, hoping to land on another.

 

But as this new study shows, by enticing a male over, E. muscae can ensure it passes into at least one more host, which will carry its spores far and wide again.

The team used a variety of chemical analysis and genetic sequencing techniques to figure out exactly what the fungus was doing, as well as exposing male flies to female partners at different stages of fungal infection, or that had died from other causes.

“Our observations suggest that this is a very deliberate strategy for the fungus,” says H. De Fine Licht. “It is a true master of manipulation – and this is incredibly fascinating.”

Tests showed that female fly corpses that had been dead for 3-8 hours attracted 15 percent of male flies, whereas with corpses that had been dead for 25-30 hours, that figure shot up to 73 percent. The more time that passed, the more chemical signals were released.

This isn’t the only time that scientists have observed sesquiterpenes being used to attract the attention of insects. As chemical signals go, it appears to be one of the most effective at manipulating these tiny creatures.

There are plenty of opportunities for further research here, not least into effective fly repellents – flies can infect humans with various diseases, and sesquiterpenes could be used to lure flies away from certain areas, such as where food is being prepared.

“This is where the Entomophthora muscae fungus may prove useful,” says H. De Fine Licht. “It might be possible for us to use these same fungal fragrances as a biological pest control that attracts healthy males to a fly trap instead of a corpse.”

The research has been published in the ISME Journal.

 

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Science

This Stunning Image Shows a Star Like You Have Never Seen One Before

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It looks a bit like neon artwork from the ’80s. But what the image above really shows is much, much cooler.

It’s a star, and the first light image captured by the newest instrument on the Gemini South telescope, the Gemini High-resolution Optical SpecTrograph, or GHOST. What it shows is the entire optical spectrum of light emitted by a star named HD 222925, in amazing resolution.

 

“This is an exciting milestone for astronomers around the globe who rely on Gemini South to study the Universe from this exceptional vantage point in Chile,” said Jennifer Lotz, director of Gemini Observatory.

“Once this next-generation instrument is commissioned, GHOST will be an essential component of the astronomer’s toolbox.”

The light we can actually see being emitted by stars is chock full of hidden details describing the distant sun’s features. It can show us whether a star is moving by how light shifts from one end of the spectrum to the other, while variations in brightness can reveal internal oscillations, which can be analyzed by asteroseismologists.

The entire spectrum of the star also reveals what it’s made of, which in turn can be used to learn all sorts of things about it, such as how old the star is, and where it formed.

That’s because different elements absorb and re-emit light differently. When astronomers look at a star’s spectrum, they can look for brighter and dimmer wavelengths, and use that information to determine which elements are present in the star’s atmosphere.

You can see what the dimmer features, known as absorption lines, look like in the image below.

The labeled spectrum of HD 222925. (International Gemini Observatory/NOIRLab/NSF/AURA/GHOST Consortium)

This technique was recently used on Hubble observations HD 222925, a really oddball star located around 1,460 light-years away. Spectral analysis revealed the most elements ever seen in a star’s atmosphere, a whopping 65 – most of which were heavy elements that can only form in extremely energetic events, such as a neutron star collision or supernova.

That means that HD 222925, which is in a very late stage at the end of its life, probably formed from a cloud that was rich in these elements in the first place, seeded by the deaths of stars that had come before it.

 

The new images from GHOST have not revealed anything new about the star – yet. The star was the target of the instrument’s ‘first light’, the first image taken by a new telescope to check the telescope is working, and how well. This allows scientists to make any necessary first adjustments to the instrument.

The commissioning phase comes next, in which scientists and technicians will put GHOST through its paces to make sure the instrument is performing as intended.

Once that stage is complete, and any further adjustments made, GHOST will be ready for scientific observation, probably around the first half of next year.

That will be something to look forward to. GHOST, which took 10 years to construct, is 10 times more powerful than Gemini’s other major optical spectrograph, GMOS. It is, scientists say, the most powerful and sensitive spectrograph of its kind currently in operation on comparable telescopes.

It’s expected that GHOST will be able to provide fascinating insights on stars identified as interesting targets by other telescopes and surveys, and deliver us many more stars, split into their constituent wavelengths – beautiful ‘star-bows’ that will hopefully unlock many hidden secrets of the Milky Way.

The images were published by NOIRLab’s International Gemini Observatory here.

 

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