The Most Amazing Space Photos This Week!


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The Most Amazing Space Photos This Week!

Northern Lights Over the Aurora Ice Museum

Credit: John Chumack/Galactic Images

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Wormholes Could Cast Weird Shadows That Could Be Seen by Telescopes


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Wormholes Could Cast Weird Shadows That Could Be Seen by Telescopes

 Wormholes Could Cast Weird Shadows That Could Be Seen by Telescopes
A model of ‘folded’ space-time illustrates how a wormhole bridge might form with at least two mouths that are connected to a single throat or tube.

Credit: edobric | Shutterstock

Wormholes, or hypothetical tunnels through space-time that allow faster-than-light travel, could potentially leave dark, telltale imprints in the sky that might be seen with telescopes, a new study suggests.

These slightly bent, oblong wormhole “shadows” could be distinguished from the more circular patches left by black holes and, if detected, could show that the cosmic shortcuts first proposed by Albert Einstein more than a century ago are, in fact, real, one researcher says.

Wormholes are cosmic shortcuts, tunnels burrowing through hyperspace. Hop in one end, and you could emerge on the other side of the universe — a convenient method of hyperfast travel that’s become a trope of science fiction. [8 Ways You Can See Einstein’s Theory of Relativity in Real Life]

These sci-fi staples arise from the equations of Einstein’s theory of general relativity. Like the space-time around black holes, wormholes are regions where the fabric of space-time is so warped, light no longer travels in a straight line. Photons — or light particles from nearby gas, dust or background stars — careen around the wormhole, generating a ring of light. But photons too close would fall through the wormhole and leave behind a dark, round void called a shadow.

Such a shadow would be similar to those cast by black holes — including the supermassive one at the center of the Milky Way galaxy — which astronomers are now trying to observe directly. Its shadow would appear tiny, so astronomers are linking radio dishes across the globe to form an Earth-sized telescope, called the Event Horizon Telescope. They’re now analyzing the first batch of data, which they collected last year.

In the new analysis, published in the preprint journal arXiv on March 30, Rajibul Shaikh, a physicist at the Tata Institute of Fundamental Research in Mumbai, India, found that a certain type of rotating wormhole would cast a larger and more distorted shadow than the one cast by a black hole. As a wormhole spun faster, its shadow would appear a little smooshed, while a black hole’s shadow would remain more disk-like.

“Through the observation of their shadows, it might be possible to distinguish between black holes and wormholes,” Shaikh told Live Science.

Researchers have calculated a rotating wormhole’s shadow before, but they overlooked the effect of the wormhole’s “throat,” which connects its two ends, Shaikh said. Using the new analysis, astronomers could, in principle, identify a wormhole shadow when they see one. And if they do, it would not only be evidence of something out of science fiction but also indirect evidence for some kind of exotic matter or a modified theory of gravity, he said.

According to general relativity, a wormhole needs exotic (and still theoretical) matter that behaves like antigravity to keep it open, or else it would collapse immediately.  Otherwise, a stable wormhole might require us to rethink our understanding of gravity, Shaikh said.

But the new analysis, which has been submitted for peer review in the journal Physical Review D, refers only to a specific class of wormholes. “It has to be studied whether or to what extent the results carry over to broader classes of wormholes,” Shaikh said.

This type of wormhole also has a simpler, unrealistic symmetry, said John Friedman, a physicist at the University of Wisconsin-Milwaukee who was not involved in the study. Shaikh’s new analysis probably wouldn’t apply to a more realistic wormhole because exotic matter is so mysterious.

“It’s highly unlikely that macroscopic wormholes exist,” Friedman told Live Science. “If they do, the unknown nature of the matter supporting the wormhole makes it impossible to predict the shadow.”

Calculating the shadow requires knowing the geometry of the space-time fabric around it. This geometry depends on the properties of exotic matter. But because no one knows what this matter might be, the exact geometry — and thus the shadow — would remain a mystery, Friedman said.

Originally published on Live Science.

How a Bizarre Nazi Military Machine Left a Lasting Mark on the Environment


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How a Bizarre Nazi Military Machine Left a Lasting Mark on the Environment

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How a Bizarre Nazi Military Machine Left a Lasting Mark on the Environment

The Germans release a colossal smoke screen in an effort to hide their battleship Tirpitz, moored in Kaa Fjord, Norway, as it’s attacked by a Lancaster on Sept. 15, 1944.

Credit: No. 5 Group RAF/IWM via Getty Images

VIENNA —The Tirpitz was the Nazis’ most imposing warship and the largest battleship ever built by a European navy. It should have been an easy target for bombers, but this massive vessel could hide in plain sight.

Hitler’s navy used a toxic artificial fog to conceal the ship when it was stationed in a Norwegian fjord. And, according to new research, this ephemeral smoke left a lasting mark on some of the living witnesses ofWorld War II: the trees.

“The effects of one military engagement during World War II are still evident in the forests of Norway, 70 years later,” said Claudia Hartl, a tree-ring researcher at the Johannes Gutenberg University in Mainz, Germany. [Images: Missing Nazi Diary Resurfaces]

Hartl, who presented her findings here during the annual meeting of the European Geosciences Union, didn’t set out to study “war dendrochronology.” Rather, she was taking core samples from pine trees around Kåfjord, near the northern edge of Scandinavia, to reconstruct a record of yearly temperatures for the past 2,000 years. (The trees can live for dozens or hundreds of years, and even older stumps can be found preserved in frigid lakes.)

“Trees are limited by temperature there, so if you have a cold year, trees form a narrow ring, and if you have a warm year, then you have wide ring,” Hartl explained.

At a site near the fjord, Hartl and her colleagues found trees that didn’t produce rings in 1945. This “exceptional stress response” didn’t fit with the researchers’ climate reconstructions, so they had to look for another explanation. And they learned that the Tirpitz had been stationed at Kåfjord, and was finally sunk by Allied bombs, in 1944.

Nicknamed “The Lonely Queen of the North” by Norwegians and “The Beast” by Winston Churchill, the battleship had been moored at Kåfjord to threaten Allied ships bringing supplies to the Soviet Union. Part of the Nazis’ defense was to release chlorosulfuric acid into the air, which attracts moisture and can create a smoke screen. Hartl said there is not much in historical records about the environmental impact of the fake fog. The substance is known to be corrosive, and the group of soldiers responsible for producing this smoke had to wear special protection suits.

The researchers sampled pine trees from six sites near the fjord. Trees farther away from the Tirpitz’s mooring were less affected by the fog. But at the site closest to the location of the battleship, 60 percent of the trees didn’t produce a ring in 1945, and some of the trees didn’t grow for several years after the war. Hartl’s team thinks the trees lost their needles due to the fog, which harmed their ability to photosynthesize.

War dendrochronology could join other nascent fields like “bombturbation” (the study of how bombs alter landscapes) as scientists begin to investigate the environmental impact of war.

“What I think is very interesting is the human impact on ecosystems,” Hartl told Live Science. “If you have a drought event, the trees also show a growth decline, but you can also see that these trees recover, and usually, it doesn’t take longer than five years. But in northern Scandinavia, through this Second World War impact, it took the trees 12 years to recover. That’s a really strong impact.”

Original article on Live Science.

This Creepy Fish Packs ‘Switchblades’ in Its Face and Could Kill You with Its Venom


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This Creepy Fish Packs ‘Switchblades’ in Its Face and Could Kill You with Its Venom

 This Creepy Fish Packs 'Switchblades' in Its Face and Could Kill You with Its Venom
This soldierfish (Gymnapistes marmoratus) has one saber in and the other saber out on either side of its head.

Credit: Copyright American Society of Ichthyologists and Herpetologists

If you invite the venomous, armored stonefish to a party, know this: It’s going to bring not one, but two “switchblades” — and it can’t check them at the door, because these weapons are embedded in its skull.

Scientists recently discovered these switchblades, or “lachrymal sabers,” in a group of stonefish — rare, dangerous fish that live in the coastal waters of the Indo-Pacific.

“I don’t [know] why this hasn’t been discovered before,” study lead researcher William Leo Smith, associate curator at the Kansas University Biodiversity Institute and Natural History Museum, said in a statement. “It’s probably because there are just one or two people that ever worked on this group.” [Photos: The Freakiest-Looking Fish]

All of the stonefish Smith analyzed have a unique type of “switchblade” mechanism on their cheeks, just below the eyes.

The ocellated waspfish (<i>Apistus carinatus</i>), also has a lachrymal saber.

The ocellated waspfish (Apistus carinatus), also has a lachrymal saber.

Credit: Leo Smith

“What makes this fish different in terms of the switchblade is that this bone [the lachrymal] is normally immobile, but these fishes can rotate the bone 90 degrees along the head-tail axis,” Smith, who is also a Kansas University associate professor of ecology and evolutionary biology, told Live Science.

In essence, the spine pokes out from the side when it’s activated, like adangerous mustache.

This rotating lachrymal saber is heavily spined, indicating that these fish use it as a weapon. When it’s not in use, the saber rests against the fish’s head, “safely pointing back and down,” Smith said.

However, when the fish goes “en garde,” it uses its cheek muscles (which are normally reserved for chewing) to pull on the upper jaw, which, in turn, rotates the spine “through a roly-poly-shaped locking mechanism,” Smith said.

Both male and female stonefish have lachrymal sabers. Depending on the individual, these spiny swords range in length from about half the width of the fish’s eye to about 2.5 times the width of the eye, Smith said. In general, large stonefish have smaller sabers, and smaller stonefish species have larger sabers, comparatively, he said.

The wispy waspfish <i>Paracentropogon longispinis</i> has a lachrymal saber.

The wispy waspfish Paracentropogon longispinis has a lachrymal saber.

Credit: Leo Smith

One species (Centropogon australis) even has a saber that glows an eerie green, thanks to biofluorescence; the saber absorbs light and then re-emits it at a lower wavelength. In a dramatic light show, the rest of the fish’s head fluoresces red, the researchers wrote in the study.

The finding is 15 years in the making. It all started in 2003, when Smith was dissecting a stonefish he had kept as a pet, and he soon became the first scientist to grasp how the locking switchblade mechanism worked anatomically.

While useful, the switchblade is just one of many defenses that stonefish likely use against predators; others include spikes, camouflage and some of the most powerful venoms in the world, which could kill even an adult human, Smith said.

“Of all the fishes I’ve studied, I haven’t yet been stung by any of these stonefishes,” Smith said in the statement. “There is an aquaculture for larger ones in Indonesia. That’s mind-boggling to me. The venom breaks down in our digestive system. But people eat lots of venomous species all over the world, even in the U.S.”

The study was published online in February in the journal Copeia.

Original article on Live Science.

NASA’s Got a Plan for a ‘Galactic Positioning System’ to Save Astronauts Lost in Space


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NASA’s Got a Plan for a ‘Galactic Positioning System’ to Save Astronauts Lost in Space

 NASA's Got a Plan for a 'Galactic Positioning System' to Save Astronauts Lost in Space
Pulsars appear to pulse due to their rotation.

Credit: NASA’s Goddard Space Flight Center

COLUMBUS, Ohio — Outer space glows with a bright fog of X-ray light, coming from everywhere at once. But peer carefully into that fog, and faint, regular blips become visible. These are millisecond pulsars, city-sized neutron stars rotating incredibly quickly, and firing X-rays into the universe with more regularity than even the most precise atomic clocks. And NASA wants to use them to navigate probes and crewed ships through deep space.

A telescope mounted on the International Space Station (ISS), the Neutron Star Interior Composition Explorer (NICER), has been used to develop a brand new technology with near-term, practical applications: a galactic positioning system, NASA scientist Zaven Arzoumanian told physicists Sunday (April 15) at the April meeting of the American Physical Society.[10 Futuristic Technologies ‘Star Trek’ Fans Would Love]

With this technology, “You could thread a needle to get into orbit around the moon of a disant planet instead of doing a flyby,” Arzoumian told Live Science. A galactic positioning system could also provide “a fallback, so that if a crewed mission loses contact with the Earth, they’d still have navigation systems on board that are autonomous.”

Right now, the kind of maneuvers that navigators would need to put a probe in orbit around distant moons are borderline impossible. In the vastness of outer space, it’s just not possible to figure out a ship’s location precisely enough to engine-firing just right. That’s a big part of why so many of the most famous planetary missions NASA has managed —Voyager 1, Juno, and New Horizons among them — have been flybys, where spacecraft have flown close to, but just past, major planetary objects. [How the Voyager Space Probes Work (Infographic)]

Relying on Earth for navigation is also a problem for crewed missions,  Arzoumian said. If that signal, connecting Earth and a distant spacecraft like a long and tenuous thread, gets somehow lost, astronauts would be hard-pressed to find their way home from Mars.

A galactic positioning system would go a long way toward solving that problem, Arzoumian said, though he cautioned he’s more a pulsar expert than a navigator. And it would work a great deal like the Global Positioning System (GPS) on your smartphone.

When your phone tries to determine its position in space, as Live Science has previously reported, it listens with its radio to the precise ticking of clock signals coming from a fleet of GPS satellites in Earth orbit. The phone’s GPS then uses the differences between those ticks to figure out its distance from each satellite, and uses that information to triangulate its own location in space.

Your phone’s GPS works fast, but Arzoumian said the galactic positioning system would work slower —taking the time needed to traverse long stretches of deep space. It would be a small, swivel-mounted X-ray telescope, which would look a lot like the big, bulky NICER stripped down to its barest minimum components. One after another, it would point at at least four millisecond pulsars, timing their X-ray “ticks” like a GPS times the ticks of satellites. Three of those pulsars would tell the spacecraft its position in space, while the fourth would calibrate its internal clock to make sure it was measuring the others properly.

Arzoumian noted that the underlying concept behind the galactic positioning system isn’t new. The famous Golden Record mounted on both Voyager spacecraft contained a pulsar map that points any aliens who one day encounter it back to planet Earth.

But this would be the first time humans have actually used pulsars to navigate. Already, Arzoumian said, his team has managed to user NICER to track the ISS through space.

NASA’s Station Explorer for X-Ray Timing and Navigation (SEXTANT) program, the team behind the Galactic Positioning System, had the goal of tracking the ISS to within 6.2 miles (10 kilometers) over the course of two weeks, Arzoumian said.

“What the demonstration back in November achieved was more like 7 kilometers [4.3 miles] in two days,” he said.

The next goal for the program is to track the station to within 1.9 miles (3 km) he said. He said that eventually the team hopes to get under 0.6 miles [1 kilometer] of precision.

“I think we can get beyond that, but I don’t know how far,” he said.

And that’s all in low-Earth orbit, he said, with the station wheeling in wild, unpredictable circles and half the sky blocked out by a giant planet, covering different pulsars every 45 minutes. In deep space, with a functionally unlimited field of view and where things mostly move in predictable, straight lines, he said, the task will be much easier.

Already, Arzoumian said, other teams within NASA have expressed interest in building the galactic positioning system into their projects. He declined to say which, not wanting to speak for them. But it seems likely that we might see such a futuristic device in action in the very near future.

Originally published on Live Science.

This Mysterious ‘Flesh-Eating’ Disease Is Spreading in Australia


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This Mysterious ‘Flesh-Eating’ Disease Is Spreading in Australia

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This Mysterious 'Flesh-Eating' Disease Is Spreading in Australia

A disease called Buruli ulcer is spreading in Australia, particularly in the state of Victoria. Above, a view of the Mornington Peninsula, an area where the disease is spreading.

Credit: Shutterstock

It sounds like a movie plot: A mysterious “flesh-eating” disease is spreading, and no one knows how to stop it. But that’s the situation health officials in Australia are facing now as they try to tackle a growing “epidemic” of a condition called Buruli ulcer.

In recent years, Australia has seen a rapid rise in cases of Buruli ulcer, an infection that causes ulcers on the skin that can destroy skin and soft tissue. In 2016, there were 186 reported cases of the infection in Australia, up from 74 cases in 2013 — an increase of 150 percent, according to the World Health Organization. Cases increased even further in 2017, with a projected 286 cases for that year, according to a new report from researchers in Victoria, Australia.

Making matters worse, scientists still don’t know how Buruli ulcer is spread, or how to prevent infection. [27 Devastating Infectious Diseases]

“As a community, we are facing a rapidly worsening epidemic of a severe disease without knowing how to prevent it,” the researchers wrote in the report, published on yeserday (April 16) in the Medical Journal of Australia. “We therefore need an urgent response” to tackle the disease, they said.

Buruli ulcer is not unique to Australia; the infection has been reported in 33 countries in Africa, South America and Western Pacific, according to the WHO. In 2016, there were 2,206 cases worldwide, with Australia and Nigeria reporting the most cases. And although cases have been reported in Australia as far back as 1948, the country has seen a spike in cases since 2013.

The situation is particularly concerning in Victoria, where cases appear to be “becoming more severe in nature, and occurring in new geographic areas,” the report said.

Buruli ulcer is caused by bacteria called Mycobacterium ulcerans, which belong to the same family of microbes that cause tuberculosis andleprosy. The bacteria produce a toxin that destroys tissue, leading to large ulcers, often on the arms or legs, the WHO says. Without early treatment, patients may develop long-term disabilities, such as limited joint movement, or require plastic surgery.

Although it’s unclear exactly how the disease is spread, researchers have some theories — for example, the disease may pass to humans from insects found in water, according to the U.S. Centers for Disease Control and Prevention. Specifically, mosquitoes have been suggested as carries of the disease; the insects have been found to test positive for M. ulcerans, and the use of insect repellent has been linked with a reduced risk of infection, according to the new report.

Animals in Australia, including possums, dogs, cats and koalas, have also been found to develop Buruli ulcer, but it’s still uncertain whether they play a role in spreading the disease, the report said. Recent evidence suggests that the infection does not spread from person-to-person.

The researchers call for a “thorough and exhaustive examination of the environment, local fauna, human behavior and characteristics, and the interactions between them” to better understand the disease and its risk factors. “It is only when we are armed with this critical knowledge that we can hope to halt the devastating impact of this disease through the design and implementation of effective public health interventions,” the researchers concluded.

Original article on Live Science.

Sharks Lay Eggs. Here’s Some Creepy Footage of What That Looks Like


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Sharks Lay Eggs. Here’s Some Creepy Footage of What That Looks Like

A shark swimming inside its egg from r/interestingasfuck

 

If you’d asked H.R. Giger to design a ravioli, you could expect it to look something like the luminous shark egg captured in a viral GIF on Reddityesterday (April 16). At first glance, it looks like a swampy green husk; but, when lit by a flashlight from behind, the slimy pouch reveals the slithering specter of a shark embryo within. And apparently, Jaws Jr. is none too pleased about the bright light shining into its home.

First of all: Yes, sharks do lay eggs. Some of them, anyway. About 70 percent of sharks are viviparous, meaning they give birth to live young; the remaining 30 percent of shark species, plus near-relatives like skates, raysand chimeras (which include the spooky “ghost shark“), are oviparous, meaning they lay eggs externally.

Each shark egg contains an embryo (baby shark) and a yolk sac (baby’s first meal), much like a chicken’s egg. Look closely in the GIF above and you can even see the umbilical cord anchoring the fluttering shark to its yolky lunchbox.

About 30 percent of sharks lay eggs like these. Can you see the baby squirming inside?

About 30 percent of sharks lay eggs like these. Can you see the baby squirming inside?

Credit: DeAgostini/Getty

Unlike chicken eggs, shark eggs are encased in a leathery, watertight shell designed to keep baby in and predators out. That leather shield is especially important because mother sharks tend to swim away from their young after laying them, leaving their progeny to fend for themselves from the very beginning.

Given their leathery exteriors and mysterious contents, egg cases that wash up on the beach are sometimes known as “mermaid’s purses.” Some species have egg cases with long, horn-like appendages on either side, and these are sometimes called “devil’s purses.” The shape and size of the purse varies from shark to shark. California horn sharks, for example, lay swirling, corkscrew-shaped eggs, all the better to nestle into the rocky nooks where mother sharks tend to lay them.

According to several Reddit commenters, the egg in the GIF above might belong to a bamboo shark, which is a popular pick for home aquariums. It’s unclear where exactly the GIF originated, but watching (or inducing) bamboo shark hatchings appears to be a popular sub-genre of YouTube’s aquarium culture. Soak up your fill of them here.

Originally published on Live Science.