Category: News Posts

Scientists Catch A White Dwarf Star In The Act Of Exploding Into A Nova

It’s not every day you get to see a star go nova. Scientists at Warsaw University Observatory in Poland have managed to catch a binary star system both before and after its explosive flash.

The findings, described in the journal Nature, confirm a long-held theory about novae known as the hibernation hypothesis – and could potentially help scientists better understand when such stellar outbursts occur.

Novae are typically caused by a gravitationally locked pair of stars, called a binary system, consisting of one white dwarf and a companion star.




A white dwarf is an aging star that has already shed much of its mass, leaving behind a small but massive core.

Like a gravitational vampire, the white dwarf siphons off material from its stellar companion – and every so often, the system becomes so unstable that the white dwarf erupts, producing a cataclysmic explosion that causes it to flare brightly in the night sky.

The most spectacular eruptions, with a ten-thousandfold increase in brightness, occur in classical novae and are caused by a thermonuclear runaway on the surface of the white dwarf,” the study authors wrote.

Such eruptions are thought to recur on time scales of ten thousand to a million years.”

Such explosions might actually have seeded the universe with some elements and radioactive isotopes, such as lithium, said lead author Przemek Mroz, an astronomer at the observatory.

About 50 novae go off every year in the Milky Way, but only five to 10 are actually observed because most of them are shrouded by interstellar gas and dust, Mroz said in an email.

The closest and brightest, however, can potentially be picked out with the naked eye.

But though novae can be seen once they go off, scientists don’t often get the chance to study them in depth before they explode.

Researchers have long had a theory about the cycle that causes these novae: When the mass transfer is low, the accretion grows unstable; every so often, the white dwarf experiences what the authors called “dwarf nova outbursts.”

Dwarf nova outbursts occur when material from the accretion disk is dumped onto the star’s surface, Mroz said; the dramatic classical nova event occurs on the surface of the white dwarf when there is enough gas to ignite thermonuclear reactions.

This is the first time [that] we observed a dwarf nova that transformed into a classical nova,” Mroz said of his team’s findings.

When the classical nova explosion finally occurs, it actually boosts the mass-transfer rate for centuries, keeping the system more stable until it dwindles and begins to approach the “hibernation” period, thus repeating the process.

But scientists couldn’t say what was really happening until the nova V1213 Cen flashed in 2009 and was caught by the university’s Optical Gravitational Lensing Experiment.

“This discovery would be impossible without long-term observations by the OGLE survey,” Mroz wrote in an email.

The survey started almost 25 years ago and for 20 years we have had a dedicated 1.3-meter telescope at Las Campanas Observatory in Chile. This is another case when OGLE data are crucial for studying unique, extremely rare phenomena.

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Fossil Holds New Insights Into How Fish Evolved Onto Land

The fossil of an early snake-like animal – called Lethiscus stocki – has kept its evolutionary secrets for the last 340-million years.

Now, an international team of researchers, led by the University of Calgary, has revealed new insights into the ancient Scottish fossil that dramatically challenge our understanding of the early evolution of tetrapods, or four-limbed animals with backbones.

Their findings have just been published in the research journal Nature.




It forces a radical rethink of what evolution was capable of among the first tetrapods,” said project lead Jason Anderson, a paleontologist and Professor at the University of Calgary Faculty of Veterinary Medicine (UCVM).

Before this study, ancient tetrapods – the ancestors of humans and other modern-day vertebrates – were thought to have evolved very slowly from fish to animals with limbs.

We used to think that the fin-to-limb transition was a slow evolution to becoming gradually less fish like,” he said.

But Lethiscus shows immediate, and dramatic, evolutionary experimentation. The lineage shrunk in size, and lost limbs almost immediately after they first evolved. It’s like a snake on the outside but a fish on the inside.

Using micro-computer tomography (CT) scanners and advanced computing software, Anderson and study lead author Jason Pardo, a doctoral student supervised by Anderson, got a close look at the internal anatomy of the fossilized Lethiscus.

After reconstructing CT scans its entire skull was revealed, with extraordinary results.

The anatomy didn’t fit with our expectations,” explains Pardo.

Many body structures didn’t make sense in the context of amphibian or reptile anatomy.” But the anatomy did make sense when it was compared to early fish.

We could see the entirety of the skull. We could see where the brain was, the inner ear cavities. It was all extremely fish-like,” explains Pardo, outlining anatomy that’s common in fish but unknown in tetrapods except in the very first.

The anatomy of the paddlefish, a modern fish with many primitive features, became a model for certain aspects of Lethiscus’ anatomy.

When they included this new anatomical information into an analysis of its relationship to other animals, Lethiscus moved its position on the ‘family tree’, dropping into the earliest stages of the fin-to-limb transition.

It’s a very satisfying result, having them among other animals that lived at the same time,” says Anderson.

The results match better with the sequence of evolution implied by the geologic record.

Lethiscus also has broad impacts on evolutionary biology and people doing molecular clock reproductions of modern animals,” says Anderson.

They use fossils to calibrate the molecular clock. By removing Lethiscus from the immediate ancestry of modern tetrapods, it changes the calibration date used in those analyses.

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The “Rockets’ Red Glare” In The Star Spangled Banner Refers Specifically To These Things

Two hundred years ago, the United States and Britain were locked in a savage struggle known as the War of 1812. After Napoleon Bonaparte abdicated in 1814, Britain sent much of its vast military capacity against the United States.

The Duke of Wellington declined the offer of command over the effort, but he did design the British grand strategy: tie down the American forces in the Chesapeake and New Orleans, then deliver the killing stroke down the Lake Champlain-Hudson River corridor, thus occupying New York City and severing New England from the rest of the country.




In all three campaigns (as well as others) these technological wonder weapons frightened American soldiers who had never seen the like before.

They were Congreve rockets, an amazing innovation in weapons technology devised by the brilliant British Army engineer William Congreve.

Congreve had served in the Anglo-Mysore War in India and had witnessed the Mysorean forces use rockets effectively against the British.

In 1805, he built and demonstrated one of his own. It was an iron cased black powder rocket on a wooden guide pole. Later versions had incendiary, shrapnel and explosive warheads.

British forces used them successfully throughout the Napoleonic Wars, then sent rocketry units to North America.

After burning Washington, D.C., the British fleet moved on to Baltimore.

Ground forces attacked American fortifications around the city while the Royal Navy attempted to neutralize Fort McHenry, which blocked access to the city’s harbor.

Over the fort flew an enormous American flag that would become known as the Star-Spangled Banner. On the night of Sept. 13-14, the fleet pummeled Fort McHenry with cannon and Congreve’s wonder weapons.

Francis Scott Key, an American prisoner on a British ship, watched the battle. He could see the flag only thanks to the light provided by the Congreve rockets.

That’s why he wrote in what would become America’s national anthem:

And the rockets’ red glare, the bombs bursting in air,
Gave proof through the night that our flag was still there;

The bombardment failed, despite William Congreve’s design efforts. But overall, the British were justifiably proud of the weapon’s war record.

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Paper-Thin Spacecraft Could Take Out The Trash In Space

NASA has awarded Aerospace a grant to investigate the possibility of developing an extremely thin spacecraft that would wrap around debris and remove it from Earth’s orbit.

The innovative concept, called Brane Craft, is a 1-meter square spacecraft that is less than half the thickness of a human hair, and therefore exceptionally light, maneuverable, and fuel efficient.

The Brane Craft concept is based on the one-dimensional compression of a complete spacecraft and upper stage into an essentially two-dimensional object in order to maximize power-to-weight and aperture-to-weight ratios,” said Dr. Siegfried Janson, the lead investigator on this project.




If you have trouble wrapping your brane, er brain, around the concept, think of the spacecraft as a large piece of high-tech plastic wrap zipping through space and enveloping flying garbage.

The Brane Craft is one of 13 ideas that were picked for the NASA Innovative Advanced Concepts (NIAC) program, which, according to NASA, “nurtures visionary ideas that could transform future NASA missions with the creation of breakthroughs — radically better or entirely new aerospace concepts.

NIAC provides $100,000 for nine months of research, with the possibility of another $500,000 for two more years if the results are promising.

Janson’s idea for the Brane Craft is definitely cutting-edge, and it could provide a solution to a difficult problem—how to get rid of all the orbital debris that could harm active spacecraft.

Janson had previously considered a concept called the Distributed Orbital Garbage Sweeper (DOGS).

DOGS would consist of many small satellites sent to “fetch” individual pieces of orbiting debris and bring them down to burn up in the atmosphere. The problem was the cost.

Sending conventional spacecraft, even CubeSats, to each of the thousands of 10-cm or larger debris objects for active deorbiting is prohibitively expensive,” Janson said.

Undaunted, Janson, who has worked in the field of small satellites for about 20 years, decided to go even smaller, at least in mass, with the Brane Craft.

To put the mass in perspective, a GPS IIF satellite weighs about 1500 kg, and a standard CubeSat is about 1 kg. The Brane Craft would only weigh about 50 grams.

The 30-micron-thick spacecraft would have a very high thrust-to-weight ratio, and would be capable of traveling long distances, which opens up other possibilities beyond just the removal of space debris.

Brane Craft prospectors could land on any near-Earth asteroid, Phobos, Deimos, a wide variety of main belt asteroids, or orbit Mars or Venus, and return,” Janson said.

Brane Craft could access just about any orbit within cis-lunar space [between Earth and the moon] several times, with propellant to spare.

It sounds great in theory, but obviously there are a number of engineering challenges associated with actually creating a flat spacecraft.

Janson has identified a number of current technologies that he believes could adapted for the Brane Craft, such as thin film solar cells and electrospray thrusters to propel the craft through space.

To allow the Brane Craft to change shape, he is considering electrostatic polymers that will contract like muscles when a voltage is applied. He’ll also be investigating thin film transistors, super flat cameras, and more.

This whole exercise is to see: can I get everything that I need for this spacecraft to fit on a thin sheet?” he said.

That’s what he will spend the next nine months researching. If successful, the Brane Craft project could provide a method of cleaning up the plethora of junk around the Earth, not to mention a really cool spacecraft with other potential uses.

According to NASA, “NIAC projects study innovative, technically credible, advanced concepts that could one day ‘change the possible’ in aerospace.”

The Brane Craft project aspires to do just that.

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1,000-Year-Old Texas Oak Tree Survives Deadly Storm

A 1,000-year-old oak tree has been found still standing in a Texas state park after Hurricane Harvey caused devastation in the area.

At least 30 people have died since Hurricane Harvey made landfall on Friday. More than 30 inches of rainfall has caused severe flooding and forced thousands of people out of their homes, seeking shelter in relief centres and local churches.




The Texas Parks and Wildlife department has been conducting search and rescue efforts with other first responders throughout the weekend as the dangerous flooding continues.

In just the first 24 hours, the department’s staff had already performed over 1,000 water rescues while more than 3,000 hurricane survivors are staying in Texas State Parks, the department said.

A total of 27 state parks have been closed due to the hurricane, including one houses the 1,000-year-old oak, which staff found was unharmed by the storm.

Goose Island State Park’s is one of the biggest living oak trees in America.

Known as the Big Tree, it has a circumference of 35 feet and 1.75 inches and an average trunk diameter of 11 feet and 2.25 inches. It is 44 feet high and has a crown spread of 89 feet.

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Astronomers Detect 15 Signals From Mysterious Object In Distant Galaxy

While looking for signs of intelligent life in the universe, astronomers have detected 15 fast radio bursts from a distant galaxy.

These poorly understood phenomena are short pulses of radio emission, just milliseconds long, believed to be coming from rapidly spinning neutron stars or black holes in distant galaxies.

A less popular theory is that they’re signs of extremely powerful spacecraft from alien civilizations.

This particular fast radio burst (FRB), called FRB 121102, is of particular interest as it is the only known one to be repeating, something that astronomers can’t yet explain.




Earlier this month, astronomers using the Green Bank Telescope in West Virginia not only found 15 more bursts, but found them at a higher radio frequency than was ever observed before, the astronomers said in their findings published in The Astronomer’s Telegram.

It’s not surprising that we’ve found 15 more from this source; we’ve been detecting many of them over the past few years,” Paul Scholz, an astronomer who studies FRBs with the Dominion Radio Astrophysical Observatory in Penticton, B.C., said.

The one thing that’s unique about these [new ones] is that they are at a higher frequency than we’ve ever seen before.

Scholz, who was not involved with the new discovery, was with McGill University when he and a team of astronomers discovered FRB 121102 to be a repeater. In 2016, a McGill team was able to locate the source of the strange FRB.

At the time the signals left its host galaxy, Earth would have been two billion years old, less than half its current age. The only living things on the planet would have been single-celled organisms.

SOLVING THE MYSTERY

As though the object wasn’t strange enough, it also behaves like no other FRB. Typically, objects that emit similar signals, such as pulsars, do so in a smooth fashion across many frequencies. But that’s not the case with FRB 121102.

So it’s kind of perplexing,” Scholz said.

Scholz said that there could be reasons such as the signal being distorted between its source galaxy and Earth.

In the coming months, a new telescope in B.C. called the Canadian Hydrogen Intensity Mapping Experiment (CHIME) is expected to begin its research into FRBs, with the possibility of discovering several a day, something that Scholz is looking forward to seeing.

It’s a mystery that needs to be solved,” Scholz said.

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A Really, Really Big Asteroid Is Going To Fly Past Earth Today!

Today, a three-mile-wide asteroid is going to fly past Earth – the biggest space rock to pass our planet this close in a century.

Asteroid 1981 ET3 – also known as 3122 Florence – will fly past safely today, September 1, 18 times further away than the moon.

While many known asteroids have passed by closer to Earth than Florence will on September 1, all of those were estimated to be smaller,” said Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies (CNEOS) at the agency’s Jet Propulsion Laboratory.




Florence is the largest asteroid to pass by our planet this close since the NASA program to detect and track near-Earth asteroids began.

The asteroid, named for Florence Nightingale, was first spotted in 1981, and the flyby in September will be the closest it’s come to Earth since 1890.

Asteroid Florence was discovered by Schelte “Bobby” Bus at Siding Spring Observatory in Australia in March 1981.

It is named in honor of Florence Nightingale (1820-1910), the founder of modern nursing.

The 2017 encounter is the closest by this asteroid since 1890 and the closest it will ever be until after 2500.

This relatively close encounter provides an opportunity for scientists to study this asteroid up close.

Florence is expected to be an excellent target for ground-based radar observations – and will also be visible to amateur astronomers via telescopes.

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Why Is Yawning So Contagious?

If looking at the image above makes you yawn, you’ve just experience contagious yawning.

What is yawning? And why do we do so much of it? Neuroscientist and yawn expert Robert Provine says it’s “ancient and autonomic.” It stems from early evolution and is common to many creatures—even fish do it.

It’s autonomic in the sense that it roots in the brainstem, way down in the basement level of the brain, where certain responses are so built-in they don’t even qualify as reflexes.

Yawning has many triggers, including boredom, sleepiness, and temperature.




A 2014 study suggested that there’s a “thermal window” (at around 68°F) for human yawning; as ambient temperature approaches body temperature or goes down near freezing, we yawn less.

According to the paper, we may yawn to regulate the temperature of our brains. This isn’t the same as saying we yawn to take in extra oxygen, as evidence to date says we don’t.

It means that yawning might act to draw brain-soothing ambient air in through the nose and mouth.

COPYCAT YAWNING?

Over the years, scientists have observed “contagious yawning” in chimpanzees, humans, baboons, bonobos, wolves, and, to a certain extent, dogs. Yawning feels good, so why not join in when someone else yawns?

Well, you’re not really “joining in,” because you aren’t copying the yawn on any conscious level. It happens because you just can’t help it. If you become self-conscious about a yawn, it stops.

While many past studies have documented the phenomenon, a more recent study, published in the journal Adaptive Human Behavior and Physiology, contends that yawns may not be contagious after all—or at least that we have not yet proven it.

Experimental psychologist Rohan Kapitány of the University of Oxford conducted a review of the scientific literature on contagious yawns and found very little conclusive evidence to back up our long-held assumption that yawns are contagious.

The belief that yawns are contagious seems self-evident,” Kapitány said, “but there are some very basic reasons for why we might be mistaken in this.”

“If we fail to dissect that which we think we know, we might end up with conclusions that do not reflect reality.”

“In this instance, the literature hasn’t questioned the basic features of contagious yawning, and ended up with a wide range of unstandardized methodologies and conclusions.

Still, because Kapitány’s study was small and extremely limited, he and his fellow authors urge other scientists to challenge their findings with experiments of their own.

I may be wrong!” Kapitány said. “Maybe yawns are contagious!” Kapitány says he’d like to see “more robust” attempts to falsify the claim that yawns are contagious rather than “simply demonstrating it over and over [in] slightly different contexts with richer and richer explanations.

WHO DOESN’T CATCH YAWNS?

Some people with autism or schizophrenia don’t exhibit a yawn-contagion response. The same is true of children under the age of four years. This has led to a variety of theories about yawning’s relationship to empathy and the brain’s mirror-neuron system (MNS).

The idea here is that MNS deficits might lead to missing hidden empathetic cues that trigger contagious yawning. The MNS seems to be involved in the process to some extent.

fMRI scans on a range of people have shown that other parts of the brain also “light up” in response to images of yawning, perhaps more so than the areas normally associated with empathy.

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Monkeys With Parkinson’s Disease Benefit From Human Stem Cells

One of the last steps before treating patients with an experimental cell therapy for the brain is confirmation that the therapy works in monkeys.

Today, scientists at the Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan, report monkeys with Parkinson’s disease symptoms show significant improvement over two years after being transplanted neurons prepared from human iPS cells.

The study, which can be read in Nature, is an expected final step before the first iPS cell-based therapy for neurodegenerative diseases.

Parkinson’s disease degenerates a specific type of cells in the brain known as dopaminergic (DA) neurons. It has been reported that when symptoms are first detected, a patient will have already lost more than half of his or her DA neurons.




Several studies have shown the transplantation of DA neurons made from fetal cells can mitigate the disease. The use of fetal tissues is controversial, however.

On the other hand, iPS cells can be made from blood or skin, which is why Professor Takahashi, who is also a neurosurgeon specializing in Parkinson’s disease, plans to use DA neurons made from iPS cells to treat patients.

Our research has shown that DA neurons made from iPS cells are just as good as DA neurons made from fetal midbrain. Because iPS cells are easy to obtain, we can standardize them to only use the best iPS cells for therapy, ” he said.

To test the safety and effectiveness of DA neurons made from human iPS cells, Tetsuhiro Kikuchi, a neurosurgeon working in the Takahashi lab, transplanted the cells into the brains of monkeys.

We made DA neurons from different iPS cells lines. Some were made with iPS cells from healthy donors. Others were made from Parkinson’s disease patients,” said Kikuchi, who added that the differentiation method used to convert iPS cells into neurons is suitable for clinical trials.

It is generally assumed that the outcome of a cell therapy will depend on the number of transplanted cells that survive, but Kikuchi found this was not the case. More important than the number of cells was the quality of the cells.

Each animal received cells prepared from a different iPS cell donor. We found the quality of donor cells had a large effect on the DA neuron survival,” Kikuchi said.

To understand why, he looked for genes that showed different expression levels, finding 11 genes that could mark the quality of the progenitors. One of those genes was Dlk1.

Dlk1 is one of the predictive markers of cell quality for DA neurons made from embryonic stem cells and transplanted into rat. We found Dlk1 in DA neurons transplanted into monkey. We are investigating Dlk1 to evaluate the quality of the cells for clinical applications.

Another feature of the study that is expected to extend to clinical study is the method used to evaluate cell survival in the host brains.

The study demonstrated that magnetic resonance imaging (MRI) and position electron tomography (PET) are options for evaluating the patient post surgery.

MRI and PET are non-invasive imaging modalities. Following cell transplantation, we must regularly observe the patient. A non-invasive method is preferred,” said Takahashi.

The group is hopeful that it can begin recruiting patients for this iPS cell-based therapy before the end of next year.

This study is our answer to bring iPS cells to clinical settings,” said Takahashi.

In a related study, the same group reports a strategy that improves the survival of the transplanted cells in monkeys. For a transplantation to succeed, the donor and patient must have matching human leukocyte antigens (HLA) to prevent tissue rejection.

The equivalent to HLA in monkeys is MHC, or major histocompatibility complex.

This study, which can be read in Nature Communications, shows that dopamine neurons derived from MHC-matched monkey iPS cells stimulate far less neuroinflammation when transplanted into monkey brains than did dopamine neurons derived from MHC-unmatched monkey iPS cells.

While this difference did not completely eliminate the need for immunosuppressants, it did lower the dosage so as to reduce the risk of infection.

The findings suggest HLA matching for iPS cell therapies will improve outcomes in patients with neurodegenerative diseases.

The combination of MHC-matching and immunosuppression will reduce the dose and duration of the immunosuppresive drug and be the best strategy for the transplantation,” said neurosurgeon and CiRA Assistant Professor Asuka Morizane.

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Company Dumps Thousands of Tons of Orange Peels onto Land. 16 Years Later, It Turns Something Surprising

Unfortunately, the world we live in today has countries all around the world burning down rainforests to fuel capitalist industries while leaving many acres of land deforested.

One example of these barren lands was Costa Rica.

Fortunately, there are some people out there who are trying to save these ecosystems – ecologists Daniel Janzen and Winnie Hallwachs.




In the 1990s, the two of them approached orange juice manufacturer Del Oro and exchanged a deal for them to donate a part of their land in exchange for the ecologists granting permission for them to deposit agricultural waste on the degraded land for free.

Del Oro agreed and dumped 1,000 truckloads of orange pulp and peels on that land.

Over the years, Del Oro offloaded over 12,000 metric tons of sticky, orange compost onto the worn-out plot until rival company TicoFruit sued, saying Del Oro had defiled the park.

TicoFruit won the lawsuit and the land went overlooked for over a decade.

A sign was placed on the site for researchers to locate and study it if they wanted to.

16 years later, environmental researches decided to evaluate the site and discovered a lush forest that had a 176 percent increase in aboveground biomass.

The researchers concluded that regenerating forests with agricultural waste could help us reduce the carbon footprint we create.

With so many food companies out there that need a way to eliminate their food waste, this is the perfect opportunity for recycling at its best.

Thanks to these two humble ecologists, they may have discovered something that could impact the future of our planet for the better.

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