livescience--2020-09-26--Are some black holes wormholes in disguise? Gamma-ray blasts may shed clues.

Unusual flashes of gamma rays could reveal that what appear to be giant are actually huge wormholes , a new study finds .
are tunnels in space-time that can theoretically allow travel anywhere in space and time , or even into another universe .
Einstein 's suggests wormholes are possible , although whether they really exist is another matter .
In many ways , wormholes resemble black holes .
Both kinds of objects are extremely dense and possess extraordinarily strong gravitational pulls for bodies their size .
The main difference is that no object can theoretically come back out after @ @ @ @ @ @ @ — the threshold where the speed needed to escape the black hole 's gravitational pull exceeds the speed of light — whereas any body entering a wormhole could theoretically reverse course .
Video : Assuming wormholes might exist , researchers investigated ways that one might distinguish a wormhole from a black hole .
They focused on supermassive black holes with masses millions to billions of times that of the sun , which are thought to dwell at the hearts of most , if not all , galaxies .
For example , at the @ @ @ @ @ @ @ a monster black hole that is about 4.5 million solar masses in size .
Anything entering one mouth of a wormhole would exit out its other mouth .
The scientists reasoned that meant that matter entering one mouth of a wormhole could potentially slam into matter entering the other mouth of the wormhole at the same time , a kind of event that would never happen with a black hole .
Any matter falling into a mouth of a supermassive wormhole would likely travel at extraordinarily high speeds due to its powerful gravitational @ @ @ @ @ @ @ of matter flowing through both mouths of a wormhole to where these mouths meet , the wormhole 's `` throat . ''
The result of such collisions are spheres of plasma expanding out both mouths of the wormhole at nearly , the researchers said .
`` What surprises me most of all is that no one has proposed this idea before , because it is rather simple , '' study lead author Mikhail Piotrovich , an astrophysicist at the Central Astronomical Observatory in Saint Petersburg , Russia , told Space.com .
The researchers @ @ @ @ @ @ @ those from a kind of supermassive black hole known as an ( AGN ) , which can spew out more radiation than our entire galaxy does as they devour matter around them , and do so from a patch of space no larger than our solar system .
AGNs are typically surrounded by rings of plasma known as accretion disks and can emit powerful jets of radiation from their poles .
The spheres of plasma from wormholes can reach temperatures of about 18 trillion degrees Fahrenheit ( 10 trillion degrees Celsius ) .
@ @ @ @ @ @ @ produce gamma rays with energies of 68 million electronvolts .
In contrast , `` accretion disks of AGNs do n't emit gamma radiation , because their temperature is too low for that , '' Piotrovich said .
Moreover , although jets from AGNs can emit gamma rays , these would mostly travel in the same direction as the jets — any traveling out in a sphere might suggest they came from a wormhole , he noted .
In addition , if an AGN resided in a kind of galaxy known as a Type @ @ @ @ @ @ @ gas was expanding rapidly — prior work suggested it would likely not generate many gamma rays with energies of 68 million electronvolts .
If astronomers did see an AGN in a Type I Seyfert galaxy with a significant peak of such rays , that could mean that seeming AGN was actually a wormhole , the researchers said .
The scientists detailed online Aug. 21 in a study accepted for publication in the journal Monthly Notices of the Royal Astronomical Society .
Follow Charles Q. Choi on Twitter @ cqchoi .
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A conceptual vision of a wormhole. Could black holes actually be colliding wormholes? A new theory says maybe.
Unusual flashes of gamma rays could reveal that what appear to be giant black holes are actually huge wormholes, a new study finds.
Wormholes are tunnels in space-time that can theoretically allow travel anywhere in space and time, or even into another universe. Einstein's theory of general relativity suggests wormholes are possible, although whether they really exist is another matter.
In many ways, wormholes resemble black holes. Both kinds of objects are extremely dense and possess extraordinarily strong gravitational pulls for bodies their size. The main difference is that no object can theoretically come back out after crossing a black hole's event horizon — the threshold where the speed needed to escape the black hole's gravitational pull exceeds the speed of light — whereas any body entering a wormhole could theoretically reverse course.
Video: Last 500 years around Milky Way's supermassive black hole
Assuming wormholes might exist, researchers investigated ways that one might distinguish a wormhole from a black hole. They focused on supermassive black holes with masses millions to billions of times that of the sun, which are thought to dwell at the hearts of most, if not all, galaxies. For example, at the center of our Milky Way galaxy lies Sagittarius A* , a monster black hole that is about 4.5 million solar masses in size.
Anything entering one mouth of a wormhole would exit out its other mouth. The scientists reasoned that meant that matter entering one mouth of a wormhole could potentially slam into matter entering the other mouth of the wormhole at the same time, a kind of event that would never happen with a black hole.
Any matter falling into a mouth of a supermassive wormhole would likely travel at extraordinarily high speeds due to its powerful gravitational fields. The scientists modeled the consequences of matter flowing through both mouths of a wormhole to where these mouths meet, the wormhole's "throat." The result of such collisions are spheres of plasma expanding out both mouths of the wormhole at nearly the speed of light , the researchers said.
"What surprises me most of all is that no one has proposed this idea before, because it is rather simple," study lead author Mikhail Piotrovich, an astrophysicist at the Central Astronomical Observatory in Saint Petersburg, Russia, told Space.com.
The researchers compared the outbursts from such wormholes with those from a kind of supermassive black hole known as an active galactic nucleus (AGN), which can spew out more radiation than our entire galaxy does as they devour matter around them, and do so from a patch of space no larger than our solar system. AGNs are typically surrounded by rings of plasma known as accretion disks and can emit powerful jets of radiation from their poles.
The spheres of plasma from wormholes can reach temperatures of about 18 trillion degrees Fahrenheit (10 trillion degrees Celsius). At such heat, the plasma would produce gamma rays with energies of 68 million electronvolts.
In contrast, "accretion disks of AGNs don't emit gamma radiation, because their temperature is too low for that," Piotrovich said. Moreover, although jets from AGNs can emit gamma rays, these would mostly travel in the same direction as the jets — any traveling out in a sphere might suggest they came from a wormhole, he noted.
In addition, if an AGN resided in a kind of galaxy known as a Type I Seyfert — one in which hot gas was expanding rapidly — prior work suggested it would likely not generate many gamma rays with energies of 68 million electronvolts. If astronomers did see an AGN in a Type I Seyfert galaxy with a significant peak of such rays, that could mean that seeming AGN was actually a wormhole, the researchers said.
The scientists detailed their findings online Aug. 21 in a study accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.
Follow Charles Q. Choi on Twitter @cqchoi. Follow us on Twitter @Spacedotcom and on Facebook.


livescience--2020-09-26--Amazing images: The best science photos of the week

Each week at Live Science we find the most interesting and informative articles we can .
Along the way , we uncover some amazing and cool images .
Here you 'll discover the most incredible photos we found this week , and the remarkable stories behind them .
The blob on the beach A mysterious , many-armed sea creature — initially described as a large `` red glob '' — lying on a rocky shore in Washington has drawn in cephalopod experts across the country , each wondering what this gelatinous animal is .
The 3.5-foot-long ( 1 meter ) @ @ @ @ @ @ @ octopus ( Haliphron atlanticus ) , a deep-water creature that is rarely seen as far north as Washington , according to the Whidbey News-Times .
Despite its intriguing name , the octopus does n't have just seven arms .
In males , the eighth arm is positioned in a sac next to the right eye , and the male takes it out when transferring sperm to potential mates .
`` Therefore it appears to have only seven arms , giving it the common name of the seven-arm octopus , '' according to a @ @ @ @ @ @ @ : Bright 'red glob ' washes ashore in Washington .
It may be a 7-armed octopus Gold miners in the Australian Outback recently discovered a gigantic crater dating to about 100 million years ago , back when dinosaurs roamed the Earth .
Found near the Western Australian town of Ora Banda , the newly dubbed Ora Banda Impact Crater is about 3 miles ( 5 kilometers ) across .
This huge hole was likely created by a meteorite up to 660 feet ( 200 meters ) wide , or longer than the length @ @ @ @ @ @ @ a Western Australia news outlet .
Geologists studying a drill core sample from the site immediately noticed shatter cones — telltale signs of a meteorite crash .
Shatter cones form when high-pressure , high-velocity shock waves from a large impacting object — such as a meteorite or a gigantic explosion ( such as would occur at a nuclear testing site ) — rattle an area .
These shock waves shatter rock into the unique shatter cone shape , just like a mark that a hard object can leave on a car 's windshield @ @ @ @ @ @ @ n't do any nuclear testing at Ora Banda , '' the evidence suggests that an ancient impact crater hit the site , geologist Jayson Meyers told Resourc.ly .
The mother of all penicillin A sample of mold that first led to the discovery of penicillin in the 1920s has been revived .
The newly awakened fungus could provide hints about how to conquer drug-resistant superbugs , .
Dr. Alexander Fleming , a professor of bacteriology in London , accidentally discovered the penicillin in 1928 , when some of his petri dishes became contaminated @ @ @ @ @ @ @ .
He extracted the active ingredient `` penicillin '' from the mold and found that it killed many kinds of harmful ; scientists later purified penicillin for use as a treatment for bacterial infections .
The mother mold was frozen and kept in storage for future study .
In new research , scientists compared Fleming 's original mold to two modern strains of Penicillium used to produce antibiotics in the U.S. , CNN reported .
They zoomed in on genes that enable the to produce penicillin ; some of these genes contain instructions @ @ @ @ @ @ @ , while others control the function and total amount of these enzymes .
Differences between the historic and modern mold strains could reveal how Penicillium has evolved through time , and whether the drug made from it could be improved , the researchers say .
Read more : Mold that led to penicillin discovery revived to fight superbugs Divers in Southeast Asia have located the lost wreck of what 's thought to be a U.S. Navy submarine that sank in 1943 after it was attacked by Japanese aircraft .
The submarine wreck was @ @ @ @ @ @ @ end of the Straits of Malacca , between the Malay peninsula and Sumatra .
The wreck is almost certainly that of the USS Grenadier , named after a type of fish like many U.S. subs , which joined the American submarine fleet in the Pacific Ocean after the in December 1941 .
It helped defend the island of Midway in June 1942 — one of the decisive naval battles of the Pacific during World War II — and later patrolled the coasts of Southeast Asia , according to the .
On April 20 @ @ @ @ @ @ @ on two Japanese cargo ships near Phuket , intending to sink them , when it was spotted by a Japanese aircraft .
The submarine crash-dived to a depth of around 120 feet ( 36 m ) , but it was hit by a torpedo dropped from the aircraft .
The stricken submarine fell to the seafloor , while its crew tried to make repairs and put out the fires ; it only surfaced after dark , 13 hours later , but it was too badly damaged to move .
Have you ever heard @ @ @ @ @ @ @ supposedly took place when an early church was constructed ?
Or how about the story of a border guard who defied King Herod 's orders and spared ' life ?
Scholars have now translated these and other `` apocryphal '' Christian texts ( stories not told in the canonical bible ) into English for the first time .
More than 300 Christian apocryphal texts are known to exist , Tony Burke , a professor of early Christianity at York University in Toronto , Canada , wrote in the book he edited `` `` @ @ @ @ @ @ @ of the newly translated texts tells of a battle against 'diabolical ' wizards who are trying to destroy an ancient church being built as a dedication to the Virgin Mary in the city of Philippi in Greece .
The text is written in Coptic , an Egyptian language that uses the Greek alphabet , and may have originally been written around 1,500 years ago , Paul Dilley , a professor of religious studies at the University of Iowa , who translated the text , wrote in the book .
The story is told @ @ @ @ @ @ @ the Monastery of Saint Macarius the Great in Egypt ( pictured above ) .
Today the two surviving copies of the text are in the Vatican Apostolic Library and the Leipzig University Library .
Smoke meets cyclones in a jarring new series of satellite images posted to .
In the images , which combine recent observations of the United States taken by several different NASA satellites from Sept. 14 to 16 , orange-tinted smoke from an immense series of wildfires on the West Coast sails clean across the country to collide with tropical @ @ @ @ @ @ @ image , from Sept. 15 , shows the two weather catastrophes directly interacting , as churning winds from Hurricane Paulette literally block wildfire smoke in the upper atmosphere from flowing further into the Atlantic Ocean .
Meanwhile , — bearing down on the Gulf Coast at the time — pushes the smoke plume further north .
When Paulette dissipated the following day , the smoke continued its eastward journey over the ocean .
These composite pictures clearly paint the intensity of the ongoing and wildfire seasons battering North America , both of which @ @ @ @ @ @ @ : Climate fires and hurricanes collide in this shocking NASA satellite image The rings of grant it a majesty befitting a planet named after the king of the Titans .
Made almost completely of bits and chunks of ice and spanning thousands of miles wide , Saturn 's rings are its most spellbinding feature ; they have mesmerized humans ever since Galileo discovered them with a telescope in 1610 .
What might be like crowned with rings ?
Space and science-fiction illustrator Ron Miller created extraordinary images of how the sky might look @ @ @ @ @ @ @ proportions to our planet as Saturn 's are to it .
The most stable place for rings is around a planet 's equator , so the appearance of the rings would vary by latitude .
For instance , near the equator at Quito , Ecuador , you would see the rings from the inner edge on , so they would look like a thin line rising straight up from the horizon .
In comparison , near the Arctic Circle , the rings might look like a hump on the horizon .
At more @ @ @ @ @ @ @ like a giant arch , crossing from one end of the sky to the other .
These glittering rings would neither rise nor set , and would always appear in the exact same place in the sky .
These cosmic landmarks would be visible both day and night .
Read more : What if Earth had rings ?
Something in the water Scientists in Botswana may finally know why more than in the country 's Okavango Delta wetlands since May .
The culprit — or one of them , anyway — appears to @ @ @ @ @ @ @ bacteria living in the region 's water holes .
`` Our latest tests have detected cyanobacterial neurotoxins to be the cause of deaths , '' Mmadi Reuben , principal veterinary officer at the Botswana department of wildlife and national parks , said during a news conference Monday ( Sept. 21 ) .
`` However , we have many questions still to be answered , such as why the elephants only and why that area only . ''
More than 70 % of the fallen were found near water sources polluted with large amounts @ @ @ @ @ @ @ known as blue-green , named for their tendency to clump together in large green mats or `` blooms '' on aquatic surfaces .
These blooms can be hazardous or even deadly , harboring toxins that attack the , skin or liver of animals exposed to them .
Toxic cyanobacteria blooms have previously caused the mass dieoffs of fish , birds and other animals , according to a 2008 study in the journal .
Read more : 350 elephants killed by ' a combination of neurotoxins ' in water , Botswana government says Humanity @ @ @ @ @ @ @ years ago .
We know from fossil evidence in and the ( modern-day Israel ) that some early members of our species expanded beyond Africa around 200,000 years ago , and again between 120,000 to 90,000 years ago .
But it was not known at what point humans turned south after crossing the Sinai Peninsula , reaching modern day Saudi Arabia .
Researchers have discovered human and other animal footprints embedded on an ancient lake surface in the Nefud Desert in Saudi Arabia that are around 120,000 years old .
These findings represent @ @ @ @ @ @ @ the Arabian Peninsula , and demonstrates the importance of Arabia for understanding human prehistory , the researchers said .
It is difficult to know which species of human left these prints , the researchers added , but they were likely Homo sapiens .
This is based on the fact that Homo sapiens were present in the Levant , 700km to the north of the Nefud Desert , at a similar time .
Neanderthals were absent from the Levant in this period and did not move back into the region until thousands of years @ @ @ @ @ @ @ Read more : Prehistoric desert footprints are earliest evidence for humans on Arabian Peninsula Planets are n't the only things in the solar system with auroras .
can have them too , data from the European Space Agency 's ( ESA ) Rosetta mission has revealed .
While looking at data from , researchers found evidence of ultraviolet auroras at , which the probe studied up close for nearly two years before the mission ended in 2016 .
`` Rosetta is the first mission to observe an ultraviolet aurora at a comet , @ @ @ @ @ @ @ scientist at ESA , .
`` Auroras are inherently exciting — and this excitement is even greater when we see one somewhere new , or with new characteristics . ''
Similar to Earth 's ( also called the Northern and Southern Lights ) , Comet 67P 's auroras appear when charged particles from the sun , known as the , interact with atoms and molecules of gas around the comet , causing them to glow .
However , the auroras on Comet 67P are not as pretty as auroras on Earth — because @ @ @ @ @ @ @ .
Earth 's auroras , which appear when solar wind interacts with atmospheric particles like oxygen and nitrogen , boast vibrant shades of green , pink , purple and blue .
But when solar wind strikes particles in the comet 's coma — the cloud of gas flowing out from a comet 's icy nucleus sometimes referred to as its `` atmosphere '' — it produces high-energy ultraviolet radiation , which is outside the range of .
• Earth from Above : 101 Stunning Images from Orbit • From Big Bang to Present @ @ @ @ @ @ @

Each week at Live Science we find the most interesting and informative articles we can. Along the way, we uncover some amazing and cool images. Here you'll discover the most incredible photos we found this week, and the remarkable stories behind them.
Gargantuan "growlers"
(Image credit: RAF)
In July 2017, a gargantuan iceberg spanning five times the area of New York's five boroughs snapped off the coast of Antarctica and began to drift northward.
Though its edges have crumbled considerably since then, the iceberg — named A-68a — is still the largest on Earth , and it's currently barreling toward an island wildlife refuge in the South Atlantic Ocean. New aerial footage taken by the United Kingdom's Royal Air Force (RAF) reveals just what that island might be up against.
For starters, the RAF footage really drives home how massive this ice giant is. (As of early April, A-68a measured about 2,000 square miles, or 5,100 square kilometers, in area, Live Science previously reported ). The berg's steep walls tower 100 feet (30 meters) above the sea, according to RAF News , and are gouged with tunnels, fissures and caves. Huge chunks of ice, or "growlers," are rapidly cracking off on all sides, leaving behind a trail of debris that could impede boat traffic in the future.
[Read more: World's largest iceberg still barreling toward penguin habitat, new footage confirms ]
Clear head, nine arms, can't lose
(Image credit: Kyodo News via Getty Images)
A nine-armed octopus caught off Japan's coast nearly ended up being dinner, until the family preparing it noticed its extra limb and sent it to a museum instead, according to news sources. While unusual, this extra appendage — which wasn't fully formed, but a small offshoot on a regular arm — isn't unheard of in octopuses, said Michael Vecchione, an invertebrate zoologist at the Smithsonian's National Museum of Natural History in Washington, D.C., who was not involved with this octopus's discovery.
Octopuses are capable of regenerating their arms, but "sometimes regeneration doesn't work quite right," Vecchione told Live Science. "If an arm gets damaged, it might regenerate wrong; it could wind up with extra tissue growing out, and that extra tissue could turn into an arm."
The nine-armed oddity was caught in a trap with three other octopuses on Nov. 13 in Shizugawa Bay, in the northeastern town of Minamisanriku, Japan, according to The Mainichi , a Japanese newspaper.
[Read more: Rare 9-armed octopus found off Japan coast ]
The sound of a supernova
(Image credit: NASA)
In space, nobody can hear you scream — or explode, or collapse, or slowly collide with a neighboring galaxy. But now, thanks to a new " data sonification " program at NASA, you can at least get a sense of what some of the most extreme phenomena in the universe might sound like when converted to sound played by Earthly instruments.
To hear what that sounds like, we turn to NASA's Chandra X-ray center — which has been imaging distant galaxies with its Chandra X-ray observatory for 20 years now. In their new initiative, Chandra researchers have taken three iconic images from their archives and translated different frequencies of light into different pitches of sound.
The first video shows the crab nebula (a supernova remnant powered by a windy neutron star , shown above). In NASA's data sonification of the nebula, X-ray light (blue and white) is represented by brass instruments; optical light (purple) is played by string instruments; and infrared light (pink) is represented by woodwinds. The sounds converge near the center of the nebula, where a rapidly swirling pulsar is blasting gas and radiation in all directions. Listen to this cosmic symphony (and two others) at the link below.
[Read more: This is what a supernova sounds like, according to NASA ]
Pterosaur's missing cousin
(Image credit: Rodolfo Nogueira)
Nearly nothing is known about the family tree of pterosaurs — iconic reptiles that flew alongside the dinosaurs . These now-extinct beasts appear in the fossil record with already developed wings and senses adapted for flying, with researchers having nary a clue about their immediate evolutionary history.
But now, the pterosaur's family tree has a new branch; an enigmatic group of small reptiles, known as lagerpetids, might be the closest-known pterosaur relatives on record, the researchers of a new study say.
Unlike pterosaurs, however, lagerpetids did not fly. "Now, we have an idea of what a flightless pterosaur relative would look like," study co-researcher Sterling Nesbitt, an associate professor of geosciences at Virginia Tech, told Live Science.
[Read more: Missing link in pterosaur origins discovered ]
The changing face of ice
(Image credit: NOAA/Photo courtesy of Caitlin Bailey, GFOE, The Hidden Ocean 2016: Chukchi Borderlands)
From vanishing sea ice to blistering air temperatures to zombie fires , climate change is reshaping the Arctic. And that transformation may be permanent, researchers said on Tuesday (Dec. 8) at the annual meeting of the American Geophysical Union (AGU).
The Arctic has warmed and melted at an alarmingly accelerating pace over the last 15 years, and the impacts are accumulating so rapidly that "there's no reason to think that in 30 years anything will be as it is today," Rick Thoman, an Alaska climate specialist with the International Arctic Research Center (IARC) at the University of Alaska Fairbanks (UAF), said at the conference, held virtually due to the COVID-19 pandemic, on Tuesday.
This year's news was not good: June snow cover across the Eurasian Arctic was at its lowest in 54 years; coastal permafrost erosion is increasing; and glaciers and ice sheets in Greenland continued a trend "of significant ice loss," according to the report.
[Read more: Dramatic transformation of the Arctic landscape may be permanent ]
Starship down
(Image credit: SpaceX)
SpaceX's Starship spaceflight system just took a big step on its path to Mars. The latest Starship prototype, a shiny silver vehicle known as SN8, launched on an epic high-altitude test flight on Dec. 9, taking off at 5:45 p.m. EST from SpaceX's facility near the South Texas village of Boca Chica.
The goal was to soar about 7.8 miles (12.5 kilometers) into the sky, perform some complex aerial maneuvers — including a "belly flop" like the one the final Starship will perform when coming back to Earth on operational flights — and then land safely near the launch stand. The 165-foot-tall (50 meters) SN8 appeared to notch all of these big milestones, except for the final one: The vehicle hit its landing mark but came in too fast, exploding in a dramatic fireball 6 minutes and 42 seconds after liftoff.
SN8's rapid unplanned disassembly did nothing to dampen the spirits of SpaceX founder and CEO Elon Musk, who was thrilled by the results of today's flight.
[Read more: SpaceX's Starship SN8 prototype soars on epic test launch, with explosive landing ]
Amazonian universe
Billions of lasers shot from a helicopter flying over the Brazilian Amazon Rainforest have detected a vast network of long-abandoned circular and rectangular-shaped villages dating from 1300 to 1700, a new study finds.
The round villages all had remarkably similar layouts, with elongated mounds circling a central plaza, like marks on a clock. "These latter elongated mounds, when seen from above, look like the rays of the sun, which gives them the common name of 'Sóis,'" the Portuguese word for "suns," the researchers wrote in the study.
The discovery is part of a new archaeological focus on the pre-Columbian Amazon. Within the past 20 years, researchers have learned that the rainforest's southern rim was home to a great diversity of soil-sculpting cultures that engineered the landscape before the Europeans arrived. Within the past decade, scientists have uncovered the remnants of so-called "mound villages," which are shaped as circles or rectangles, and connected by road networks.
[Read more: Archaeologists find vast network of Amazon villages laid out like the cosmos ]
The sky is falling
(Image credit: ESA)
Have you ever seen 40,000 shooting stars blaze across the sky at the same time?
If you'd like to, the European Space Agency (ESA) is offering you two options: Either stare at the night sky for about half a million years as our solar system drifts steadily through the Milky Way (some patience required) — or, watch a new 60-second time-lapse simulation of the same thing, courtesy of the ESA's Gaia space observatory.
In the new simulation, 40,000 stars — all located within 325 light-years of Earth's sun — whiz through space, leaving long trails of light behind them. Each point of light represents one real object in the Milky Way, and each shining trail shows that object's projected movement through the galaxy over the next 400,000 years. Brighter, faster streaks are located closer to our solar system, while dimmer, slower ones live much farther away.
[Read more: Epic time-lapse shows what the Milky Way will look like 400,000 years from now ]
Gold in the garden
(Image credit: © The Trustees of the British Museum)
A family in England was weeding their garden when they unearthed a valuable treasure — a buried hoard of gold coins dating back to the 1400s, depicting English monarchs from Edward IV to Henry VIII.
The hoard — a stash of 63 gold coins and one silver coin — contains money minted over a period of nearly 100 years, from the late 15th to the 16th centuries. Four of the coins feature Henry VIII and, curiously, one of the initials of three of his wives: Catherine of Aragon, Anne Boleyn and Jane Seymour.
Upon finding the cache, the family, in the New Forest district of Hampshire, a county in southeastern England, notified the British Museum, which runs the Portable Antiquities Scheme (PAS). This program partners with local people who find historical artifacts in the United Kingdom, so the findings can be documented and studied, the British Museum said in a statement Thursday (Dec. 10).
[Read more: Gold coin stash from time of Henry VIII found in English garden ]
Enigma of the deep
(Image credit: Florian Huber/WWF)
Divers trying to remove old fishing nets from the Baltic sea have accidentally stumbled on a Nazi code-making machine. The Enigma machine, as it's called, looks a bit like a typewriter. In fact, the diver who found the device on the ocean floor initially thought that's what the artifact was, according to AFP . But the diving team, on assignment for the conservation group World Wide Fund for Nature (WWF), quickly realized that they had something much stranger.
During World War II, Enigma machines were used to encode German military messages, in hopes of preventing Allied powers from learning about troop movements and other plans. The devices consisted of a keyboard and a series of rotors that did the encoding. The rotors substituted different letters for the ones typed in; different Enigma machines used between three and eight rotors, which moved independently after each keystroke so that the same initial letter typed into the machine would appear as multiple different letters in the final code.
The Enigma machine found by the WWF diving crew was at the bottom of the Bay of Gelting in northeast Germany. It had three rotors, making it the type used on warships, not U-boats. That suggests that the machine may have been tossed overboard in the final days of World War II, in an attempt to keep the technology out of enemy hands, historian Jann Witt of the German Naval Association told the DPA news agency.
[Read more: Nazi 'Enigma' machine found at the bottom of the Baltic Sea ]
Originally published on Live Science.


livescience--2020-09-27--Could the Sahara ever be green again?

Could the Sahara ever be green again?

Sometime between 11,000 and 5,000 years ago , after the last ice age ended , the transformed .
Green vegetation grew atop the sandy dunes and increased rainfall turned arid caverns into lakes .
About 3.5 million square miles ( 9 million square kilometers ) of Northern Africa turned green , drawing in animals such as , antelopes , and aurochs ( wild ancestors of domesticated cattle ) , who feasted on its thriving grasses and shrubs .
This lush paradise is long gone , but could it ever return ?
In short , the answer is yes .
The @ @ @ @ @ @ @ African Humid Period , was caused by the Earth 's constantly changing orbital rotation around its axis , a pattern that repeats itself every 23,000 years , according to Kathleen Johnson , an associate professor of Earth systems at the University of California Irvine .
However , because of a wildcard — human-caused that have led to runaway — it 's unclear when the Sahara , currently the world 's largest hot desert , will turn a new green leaf .
Related : Has the Earth ever been this hot before ?
The @ @ @ @ @ @ @ 's tilt changed .
About 8,000 years ago , the tilt began moving from about 24.1 degrees to the current day 23.5 degrees , Space.com , a Live Science sister site , .
That tilt variation made a big difference ; right now , the Northern Hemisphere is closest to the sun during the winter months .
( This may sound counterintuitive , but because of the current tilt , the Northern Hemisphere is tilted away from the sun during the winter season . )
During the Green Sahara , however , the @ @ @ @ @ @ @ during the summer .
This led to an increase in solar radiation ( in other words , heat ) in Earth 's Northern Hemisphere during the summer months .
The rise in solar radiation amplified the African , a seasonal wind shift over the region caused by temperature differences between the land and ocean .
The increased heat over the Sahara created a low pressure system that ushered moisture from the Atlantic Ocean into the barren desert .
( Usually , the wind blows from dry land toward the Atlantic , spreading dust @ @ @ @ @ @ @ beaches in the Caribbean , . )
This increased moisture transformed the formerly sandy Sahara into a grass and shrub-covered steppe , according to the National Oceanic and Atmospheric Administration ( NOAA ) .
As animals there prospered , humans did too , eventually domesticating buffalo and goats and even creating an early system of symbolic art in the region , NOAA reported .
But why did Earth 's tilt change in the first place ?
To understand this monumental change , scientists have looked to Earth 's neighbors in the solar system @ @ @ @ @ @ @ is perturbed by gravitational interactions with the moon and the more massive planets that together induce periodic changes in the Earth 's orbit , '' Peter de Menocal , the director at the Center for Climate and Life at Lamont-Doherty Earth Observatory at Columbia University in New York , .
One such change is a `` wobble '' in the Earth 's axis , he wrote .
That wobble is what positions the Northern Hemisphere closer to the sun in the summer — what researchers call a Northern Hemisphere summer insolation maximum — @ @ @ @ @ @ @ first published in the journal in 1981 , scholars estimate that the Northern Hemisphere had a 7 % increase in solar radiation during the Green Sahara compared with now .
This increase could have escalated African monsoonal rainfall by 17 % to 50 % , according to a 1997 study published in the journal .
What 's interesting to climate scientists about the Green Sahara is how it appeared and vanished .
The termination of the Green Sahara took only 200 years , Johnson said .
The change in solar radiation was gradual @ @ @ @ @ @ @ `` It 's an example of abrupt climate change on a scale humans would notice , '' she said .
`` Records from ocean sediment show [ that the Green Sahara ] happens repeatedly , '' Johnson told Live Science .
The next Northern Hemisphere summer insolation maximum — when the Green Sahara could reappear — is projected to happen again about 10,000 years from now in A.D. 12000 or A.D. 13000 .
But what scientists ca n't predict is how greenhouse gases will affect this natural climate cycle .
Paleoclimate research `` @ @ @ @ @ @ @ ] are doing is pretty unprecedented , '' Johnson said .
Even if humans stop emitting greenhouse gases today , these gases would still be elevated by the year 12000 .
`` Climate change will be superimposed onto the Earth 's natural climate cycles , '' she said .
That said , there 's geologic evidence from ocean sediments that these orbitally-paced Green Sahara events occur as far back as the Miocene epoch ( 23 million to 5 million years ago ) , including during periods when atmospheric carbon dioxide was similar to @ @ @ @ @ @ @ 's levels .
So , a future Green Sahara event is still highly likely in the distant future .
Today 's rising greenhouse gases could even have their own greening effect on the Sahara , though not to the degree of the orbital-forced changes , according to a March review published in the journal One Earth .
But this idea is far from certain , due to climate model limitations .
Meanwhile , there is another way to turn parts of the Sahara into a green landscape ; if massive solar and wind @ @ @ @ @ @ @ increase in the Sahara and its southern neighbor , the semiarid Sahel , according to a 2018 study published in the journal .
Wind and solar farms can increase heat and humidity in the areas around them , .
An increase in precipitation , in turn , could lead vegetation growth , creating a positive feedback loop , the researchers of that study said .
However , this huge undertaking has yet to be tested in the Sahara Desert , so until such a project gets funding , humans might have to wait @ @ @ @ @ @ @ see whether the Sahara will turn green again .

Sometime between 11,000 and 5,000 years ago, after the last ice age ended, the Sahara Desert transformed. Green vegetation grew atop the sandy dunes and increased rainfall turned arid caverns into lakes. About 3.5 million square miles (9 million square kilometers) of Northern Africa turned green, drawing in animals such as hippos , antelopes, elephants and aurochs (wild ancestors of domesticated cattle), who feasted on its thriving grasses and shrubs. This lush paradise is long gone, but could it ever return?
In short, the answer is yes. The Green Sahara, also known as the African Humid Period, was caused by the Earth's constantly changing orbital rotation around its axis, a pattern that repeats itself every 23,000 years, according to Kathleen Johnson, an associate professor of Earth systems at the University of California Irvine.
However, because of a wildcard — human-caused greenhouse gas emissions that have led to runaway climate change — it's unclear when the Sahara, currently the world's largest hot desert, will turn a new green leaf.
Related: Has the Earth ever been this hot before?
The Sahara's green shift happened because Earth's tilt changed. About 8,000 years ago, the tilt began moving from about 24.1 degrees to the current day 23.5 degrees, Space.com, a Live Science sister site, previously reported . That tilt variation made a big difference; right now, the Northern Hemisphere is closest to the sun during the winter months. (This may sound counterintuitive, but because of the current tilt, the Northern Hemisphere is tilted away from the sun during the winter season.) During the Green Sahara, however, the Northern Hemisphere was closest to the sun during the summer.
Notice how the Northern Hemisphere is closer to the sun during the winter months (right) than it is during the summer months. (Image credit: Shutterstock)
This led to an increase in solar radiation (in other words, heat) in Earth's Northern Hemisphere during the summer months. The rise in solar radiation amplified the African monsoon , a seasonal wind shift over the region caused by temperature differences between the land and ocean. The increased heat over the Sahara created a low pressure system that ushered moisture from the Atlantic Ocean into the barren desert. (Usually, the wind blows from dry land toward the Atlantic, spreading dust that fertilizes the Amazon rainforest and builds beaches in the Caribbean, Live Science previously reported .)
This increased moisture transformed the formerly sandy Sahara into a grass and shrub-covered steppe, according to the National Oceanic and Atmospheric Administration (NOAA). As animals there prospered, humans did too, eventually domesticating buffalo and goats and even creating an early system of symbolic art in the region, NOAA reported.
Image 1 of 6 The Aorounga impact structure is located in northern Chad, in the Sahara Desert. (Image credit: ISS Crew Earth Observations, Image Science & Analysis Laboratory; Johnson Space Center; NASA) This 2014 photo from the International Space Station shows cloud bands over southern Mauritania in the Sahara Desert. (Image credit: ISS Crew Earth Observations; Image Science & Analysis Laboratory, Johnson Space Center; NASA) These dried-up river channels in Algeria, a country that is mostly covered by the Sahara Desert, are known as wadis. (Image credit: Image by Robert Simmon; NASA GSFC, based on Landsat Thematic Mapper data) About 134 miles (215 kilometers) of the Saharan coastline were captured in this 2014 image taken from the International Space Station. (Image credit: SS Crew Earth Observations Facility; Earth Science and Remote Sensing Unit, Johnson Space Center; NASA) More dust is blown out of the Sahara than any other desert in the world, according to NASA's Earth Observatory. The International Space Station was over Libya when this photo was taken in 2014. (Image credit: ISS Crew Earth Observations Facility; Earth Science and Remote Sensing Unit, Johnson Space Center; NASA) In March 2018, Saharan dust plastered parts of Europe, coating ski slopes and Mediterranean cities in orange particles, according to NASA's Earth Observatory. (Image credit: NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response)
Wobbling Earth
But why did Earth's tilt change in the first place? To understand this monumental change, scientists have looked to Earth's neighbors in the solar system.
"The Earth's axial rotation is perturbed by gravitational interactions with the moon and the more massive planets that together induce periodic changes in the Earth's orbit," Peter de Menocal, the director at the Center for Climate and Life at Lamont-Doherty Earth Observatory at Columbia University in New York, wrote in Nature . One such change is a "wobble" in the Earth's axis, he wrote.
That wobble is what positions the Northern Hemisphere closer to the sun in the summer — what researchers call a Northern Hemisphere summer insolation maximum — every 23,000 years. Based on research first published in the journal Science in 1981, scholars estimate that the Northern Hemisphere had a 7% increase in solar radiation during the Green Sahara compared with now. This increase could have escalated African monsoonal rainfall by 17% to 50%, according to a 1997 study published in the journal Science .
Related: Why does rain smell good?
What's interesting to climate scientists about the Green Sahara is how abruptly it appeared and vanished. The termination of the Green Sahara took only 200 years, Johnson said. The change in solar radiation was gradual, but the landscape changed suddenly. "It's an example of abrupt climate change on a scale humans would notice," she said.
"Records from ocean sediment show [that the Green Sahara] happens repeatedly," Johnson told Live Science. The next Northern Hemisphere summer insolation maximum — when the Green Sahara could reappear — is projected to happen again about 10,000 years from now in A.D. 12000 or A.D. 13000. But what scientists can't predict is how greenhouse gases will affect this natural climate cycle.
Paleoclimate research "provides unequivocal evidence to what [humans] are doing is pretty unprecedented," Johnson said. Even if humans stop emitting greenhouse gases today, these gases would still be elevated by the year 12000. "Climate change will be superimposed onto the Earth's natural climate cycles," she said.
That said, there's geologic evidence from ocean sediments that these orbitally-paced Green Sahara events occur as far back as the Miocene epoch (23 million to 5 million years ago), including during periods when atmospheric carbon dioxide was similar to, and possibly higher, than today's levels. So, a future Green Sahara event is still highly likely in the distant future. Today's rising greenhouse gases could even have their own greening effect on the Sahara, though not to the degree of the orbital-forced changes, according to a March review published in the journal One Earth. But this idea is far from certain, due to climate model limitations.
Meanwhile, there is another way to turn parts of the Sahara into a green landscape; if massive solar and wind farms were installed there, rainfall could increase in the Sahara and its southern neighbor, the semiarid Sahel, according to a 2018 study published in the journal Science .
Wind and solar farms can increase heat and humidity in the areas around them, Live Science previously reported . An increase in precipitation, in turn, could lead vegetation growth, creating a positive feedback loop, the researchers of that study said. However, this huge undertaking has yet to be tested in the Sahara Desert, so until such a project gets funding, humans might have to wait until the year 12000 or longer to see whether the Sahara will turn green again.
Originally published on Live Science.


livescience--2020-09-27--We may finally know what life on Earth breathed before there was oxygen

Billions of years ago , long before oxygen was readily available , the notorious poison arsenic could have been the compound that breathed new life into our planet .
In Chile 's Atacama Desert , in a place called Laguna La Brava , scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that 's permanently free of oxygen .
`` I have been working with microbial mats for about 35 years or so , '' says geoscientist Pieter Visscher from the University of Connecticut .
`` This is the only system on Earth where @ @ @ @ @ @ @ worked absolutely in the absence of oxygen . ''
Microbial mats , which fossilize into stromatolites , have been abundant on Earth for at least 3.5 billion years , and yet for the first billion years of their existence , there was no oxygen for photosynthesis .
How these life forms survived in such extreme conditions is still unknown , but examining stromatolites and extremophiles living today , researchers have figured out a handful of possibilities .
While iron , sulphur , and hydrogen have long been proposed as possible replacements for oxygen @ @ @ @ @ @ @ of 'arsenotrophy ' in California 's hypersaline Searles Lake and Mono Lake that arsenic also became a contender .
Since then , stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian .
The same could n't be said of iron or sulphur .
Just last year , researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic .
Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp.
@ @ @ @ @ @ @ arsenic-rich lake in Nevada and which appears to photosynthesize by oxidising the compound arsenite into a different form -arsenate .
While more research needs to verify whether the La Brava microbes also metabolize arsenite , initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic .
If the authors are right and the La Brava microbes are indeed 'breathing ' arsenic , these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat , similar to what we would @ @ @ @ @ @ @ , its mats are a great model for understanding some of the possible earliest life forms on our planet .
While genomic research suggests the La Brava mats have the tools to metabolize arsenic and sulphur , the authors say its arsenate reduction appears to be more effective than its sulfate reduction .
Regardless , they say there 's strong evidence that both pathways exist , and these would have been enough to support extensive microbial mats in the early days of life on Earth .
If the team is right , then @ @ @ @ @ @ @ for life forms elsewhere .
`` In looking for evidence of life on Mars , [ scientists ] will be looking at iron and probably they should be looking at arsenic also , '' says Visscher .
It really is so much more than just a poison .
The study was published in Communications Earth and Environment .
This article was originally published by ScienceAlert .
Read the original article here .

Billions of years ago, long before oxygen was readily available, the notorious poison arsenic could have been the compound that breathed new life into our planet.
In Chile's Atacama Desert, in a place called Laguna La Brava, scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that's permanently free of oxygen.
"I have been working with microbial mats for about 35 years or so," says geoscientist Pieter Visscher from the University of Connecticut.
"This is the only system on Earth where I could find a microbial mat that worked absolutely in the absence of oxygen."
Microbial mats, which fossilize into stromatolites, have been abundant on Earth for at least 3.5 billion years, and yet for the first billion years of their existence, there was no oxygen for photosynthesis.
How these life forms survived in such extreme conditions is still unknown, but examining stromatolites and extremophiles living today, researchers have figured out a handful of possibilities.
While iron, sulphur, and hydrogen have long been proposed as possible replacements for oxygen, it wasn't until the discovery of 'arsenotrophy' in California's hypersaline Searles Lake and Mono Lake that arsenic also became a contender.
Since then, stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian. The same couldn't be said of iron or sulphur.
Just last year, researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic.
Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp., which was recently found in an arsenic-rich lake in Nevada and which appears to photosynthesize by oxidising the compound arsenite into a different form -arsenate.
While more research needs to verify whether the La Brava microbes also metabolize arsenite, initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic.
If the authors are right and the La Brava microbes are indeed 'breathing' arsenic, these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat, similar to what we would expect in Precambrian environments.
As such, its mats are a great model for understanding some of the possible earliest life forms on our planet.
While genomic research suggests the La Brava mats have the tools to metabolize arsenic and sulphur, the authors say its arsenate reduction appears to be more effective than its sulfate reduction.
Regardless, they say there's strong evidence that both pathways exist, and these would have been enough to support extensive microbial mats in the early days of life on Earth.
If the team is right, then we might need to expand our search for life forms elsewhere.
"In looking for evidence of life on Mars, [scientists] will be looking at iron and probably they should be looking at arsenic also," says Visscher.
It really is so much more than just a poison.
The study was published in Communications Earth and Environment.
This article was originally published by ScienceAlert. Read the original article here.


livescience--2020-09-28--Coronavirus spike protein morphs into 10 different shapes to invade cells

The novel uses its `` spike proteins '' to latch onto and invade human cells .
But to do so , the spikes morph into at least 10 different shapes , according to a new study .
At the start of the , scientists rapidly identified the structure of the , paving the way to target it with vaccines and other drugs .
But there 's still so much scientists do n't know about the interaction between the spike protein and the `` doorknob '' on the outsides of human cells — called the ACE2 protein .
For instance , @ @ @ @ @ @ @ the protein takes to kickstart the process of fusing to , and then opening the cell , ultimately dumping viral material into the cell .
`` The spike protein is the focus of so much research at the minute , '' said co-lead author Donald Benton , a postdoctoral research fellow at the Francis Crick Institute 's Structural Biology of Disease Processes Laboratory in the United Kingdom .
Understanding how it functions `` is very important because it 's the target of most of the vaccination attempts and a lot of diagnostic work @ @ @ @ @ @ @ process of infection , Benton and his team mixed human ACE2 proteins with spike proteins in the lab .
They then used a very cold liquid ethane to rapidly freeze the proteins such that they became `` suspended in a special form of ice , '' Benton told Live Science .
They then put these samples under a cryo-electron microscope and obtained tens of thousands of high-resolution images of the spike proteins frozen at different stages of binding to the ACE2 receptors .
They found that the spike protein undergoes shape changes as @ @ @ @ @ @ @ After the spike protein first binds , its structure becomes more open to allow for more binding ( imagine how much easier it would be to hug someone if they opened up their arms ) .
The spike protein eventually binds to ACE2 at all three of its binding sites , revealing it 's `` central core , '' according to a statement .
This final structure likely allows the virus to fuse to cell membranes .
`` It 's a very complicated receptor binding process compared to most virus spike proteins , @ @ @ @ @ @ @ more simple activation process . ''
The coronavirus is covered in spike proteins , and it 's likely only a small fraction of them go through these conformational changes , bind to human cells and infect them , Benton said .
`` We know that the spike can adopt all these states that we were talking about , '' said co-lead author Antoni Wrobel , who is also a postdoctoral research fellow at the Francis Crick Institute 's Structural Biology of Disease Processes Laboratory .
`` But whether each of the spikes adopts @ @ @ @ @ @ @ because we can see only kind of snapshots . ''
The spike protein is very quick to change .
In the lab , the spike can morph into all of these different conformations in less than 60 seconds , Wrobel told Live Science .
But `` this will be very different in a real infection ; everything will be slower because the receptor will be stuck on the surface of a cell so you have to allow time for the virus to diffuse to this receptor , '' Benton said .
Why does @ @ @ @ @ @ @ conformational changes to infect a cell ?
It `` may be a way of the virus protecting itself from recognition by , '' Benton said .
When the spike protein is in its closed states , it hides the site that binds with the receptor , maybe to avoid antibodies coming in and binding to that site instead , he said .
But `` it 's very hard to know , '' Wrobel said .
In any case , this research reveals more surfaces on the spike protein that are exposed during infection @ @ @ @ @ @ @ thought hidden .
Researchers can then potentially develop vaccines to target these surfaces .
`` We can then start to think about therapeutics that would fit somewhere either in the receptor surface or somewhere in the spike itself that then act as drugs , '' Wrobel told Live Science .
Wrobel and Benton hope to figure out why the coronavirus goes through so many conformational changes , how that compares to other coronaviruses and if these changes might help explain why this new virus spreads so easily .
The findings were published Sept. @ @ @ @ @

The novel coronavirus uses its "spike proteins" to latch onto and invade human cells. But to do so, the spikes morph into at least 10 different shapes, according to a new study.
At the start of the pandemic , scientists rapidly identified the structure of the spike protein , paving the way to target it with vaccines and other drugs. But there's still so much scientists don't know about the interaction between the spike protein and the "doorknob" on the outsides of human cells — called the ACE2 protein. For instance, they aren't sure what intermediate steps the protein takes to kickstart the process of fusing to, and then opening the cell, ultimately dumping viral material into the cell.
"The spike protein is the focus of so much research at the minute," said co-lead author Donald Benton, a postdoctoral research fellow at the Francis Crick Institute's Structural Biology of Disease Processes Laboratory in the United Kingdom. Understanding how it functions "is very important because it's the target of most of the vaccination attempts and a lot of diagnostic work as well."
Related: Coronavirus live updates
To understand the process of infection, Benton and his team mixed human ACE2 proteins with spike proteins in the lab. They then used a very cold liquid ethane to rapidly freeze the proteins such that they became "suspended in a special form of ice," Benton told Live Science. They then put these samples under a cryo-electron microscope and obtained tens of thousands of high-resolution images of the spike proteins frozen at different stages of binding to the ACE2 receptors.
The spike protein undergoes a handful of conformations as it binds to the ACE2 receptor that sits on the surface of some human cells. (Image credit: The Francis Crick Institute)
They found that the spike protein undergoes shape changes as it binds to the ACE2 receptor. After the spike protein first binds, its structure becomes more open to allow for more binding (imagine how much easier it would be to hug someone if they opened up their arms). The spike protein eventually binds to ACE2 at all three of its binding sites, revealing it's "central core," according to a statement. This final structure likely allows the virus to fuse to cell membranes.
"It's a very complicated receptor binding process compared to most virus spike proteins," Benton said. " Flu and HIV have a more simple activation process." The coronavirus is covered in spike proteins, and it's likely only a small fraction of them go through these conformational changes, bind to human cells and infect them, Benton said.
"We know that the spike can adopt all these states that we were talking about," said co-lead author Antoni Wrobel, who is also a postdoctoral research fellow at the Francis Crick Institute's Structural Biology of Disease Processes Laboratory. "But whether each of the spikes adopts all of them we can't say because we can see only kind of snapshots."
The spike protein is very quick to change. In the lab, the spike can morph into all of these different conformations in less than 60 seconds, Wrobel told Live Science. But "this will be very different in a real infection; everything will be slower because the receptor will be stuck on the surface of a cell so you have to allow time for the virus to diffuse to this receptor," Benton said.
Why does the spike protein go through this many conformational changes to infect a cell? It "may be a way of the virus protecting itself from recognition by antibodies ," Benton said. When the spike protein is in its closed states, it hides the site that binds with the receptor, maybe to avoid antibodies coming in and binding to that site instead, he said.
But "it's very hard to know," Wrobel said. In any case, this research reveals more surfaces on the spike protein that are exposed during infection — as different shapes reveal surfaces once thought hidden. Researchers can then potentially develop vaccines to target these surfaces. "We can then start to think about therapeutics that would fit somewhere either in the receptor surface or somewhere in the spike itself that then act as drugs," Wrobel told Live Science.
Wrobel and Benton hope to figure out why the coronavirus goes through so many conformational changes, how that compares to other coronaviruses and if these changes might help explain why this new virus spreads so easily.
The findings were published Sept. 17 in the journal Nature .
Originally published on Live Science.


livescience--2020-09-28--Watch SpaceX launch 60 new Starlink internet satellites into orbit today

CAPE CANAVERAL , Fla. — will launch its next big batch of into orbit for the company 's growing megaconstellation today ( Sept. 28 ) , and you can watch the action live online .
The Hawthorne , California-based company will loft 60 Starlink internet satellites on its workhorse from NASA 's historic Pad 39A here at Kennedy Space Center in Florida at 10:22 a.m. EDT ( 1422 GMT ) .
You can and on the Space.com homepage , courtesy of SpaceX , beginning about 15 minutes before liftoff .
You can also .
Today ’ s flight , referred @ @ @ @ @ @ @ is actually the 13th big batch of satellites the company has shot into space .
However , the company has been systematically de-orbiting its initial batch of 60 satellites that were launched in May 2019 .
That ’ s because SpaceX always meant for that initial bunch to be a test series .
Thus far , 26 of the original satellites have been deorbited , eight are in decaying orbits , and 26 are operational .
SpaceX hopes to provide high-speed internet access to users around the world through the Starlink megaconstellation .
@ @ @ @ @ @ @ larger than a laptop ) , users on the ground will be able to connect to the ever-growing network .
SpaceX founder and CEO has said that the company needs to launch between 500 and 800 satellites in order to begin rolling out service .
To date , SpaceX has launched more than 700 of the internet-beaming satellites into orbit , in an effort to fill out its planned initial constellation of 1,440 spacecraft .
SpaceX has already begun speed-testing its space-based internet service , and the initial data looks promising .
Company @ @ @ @ @ @ @ far indicates that the service will provide fast download speeds , allowing users to stream multiple HD movies at the same time .
The Starlink broadband internet is in a private beta-testing phase now , but it will be available for the public to start beta-testing later this year , SpaceX representatives have said .
Today 's launch marks the 94st flight overall for SpaceX ’ s workhorse two-stage Falcon 9 rocket .
The liftoff is expected to feature a veteran Falcon 9 first stage , designated B1058 , that has two flights @ @ @ @ @ @ @ previously launched on a trip to the space station as well as a for the South Korean military .
Flying previously flown boosters has become commonplace for SpaceX , as the company continues to prove the Falcon 9 's reliability .
SpaceX is both the launch provider as well as the customer for its Starlink missions , and as such has kept up a rapid launch pace this summer , relying heavily on its fleet of flight-proven boosters .
In fact , this mission marks the 17th flight of 2020 for SpaceX , @ @ @ @ @ @ @ — a superlative it snagged from a chief competitor , United Launch Alliance 's Atlas V. To date , SpaceX has successfully landed its first-stage boosters 60 times .
Now that the company has two fully operational drone-ship landing platforms — `` Of Course I Still Love You '' and `` Just Read the Instructions '' — in Florida , it ’ s able to launch ( and land ) more rockets .
The newer drone ship on the block , `` Just Read the Instructions , '' is already at the recovery @ @ @ @ @ @ @ B1058 when it returns to Earth this afternoon .
This is SpaceX 's second attempt to get this mission off the ground .
The previous attempt on Sept. 17 , was called off due to poor weather conditions at the recovery zone .
Activity in the Atlantic Ocean is very busy this year , with several storm systems developing .
One such system , Hurricane Paulette , has been keeping the seas churned up so that the drone ship “ Just Read the Instructions ” could not stabilize itself enough to catch the @ @ @ @ @ @ @ stand down from its original launch attempt and wait for calmer seas .
The delay worked in SpaceX 's favor as it brought fairer weather and calmer seas .
Forecasters at the 45th Weather Squadron predicted a 70 % chance of favorable launch conditions today .
The only issue was the possible development of cumulus clouds .
SpaceX will continue its tradition of recovering the Falcon 9 's payload fairing , or nose cone , on today 's flight .
The company has already deployed its twin net-equipped boats — called GO Ms. @ @ @ @ @ @ @ snag the fairing halves as they fall back to Earth in two pieces .
Each piece of the clamshell-like hardware , which cost approximately $ 6 million combined , is outfitted with software that navigates it to the recovery zone , and a parachute system that lets them gently land in the ocean or the outstretched net of GO Ms. Tree and GO Ms. Chief .
One of the pieces of the fairing on this mission has flown twice already , protecting two different Starlink payloads — one in May 2019 and one @ @ @ @ @ @ @ : This story , originally posted Sept. 17 , has been updated for SpaceX 's new launch date of Sept. 28 .
Follow Amy Thompson on Twitter @ astrogingersnap .
Follow us on Twitter @ Spacedotcom or Facebook .

SpaceX will launch 60 new Starlink internet satellites from Pad 39A of NASA's Kennedy Space Center in Cape Canaveral, Florida on Sept. 28, 2020. Shown here: A different Falcon launches the Starlink 11 mission on Sept. 3 from the same pad.
CAPE CANAVERAL, Fla. — SpaceX will launch its next big batch of Starlink satellites into orbit for the company's growing megaconstellation today (Sept. 28), and you can watch the action live online.
The Hawthorne, California-based company will loft 60 Starlink internet satellites on its workhorse Falcon 9 rocket from NASA's historic Pad 39A here at Kennedy Space Center in Florida at 10:22 a.m. EDT (1422 GMT).
You can watch the launch live here and on the Space.com homepage, courtesy of SpaceX, beginning about 15 minutes before liftoff. You can also watch the launch directly via SpaceX .
Related: SpaceX's Starlink satellite megaconstellation launches in photos
Today’s flight, referred to as Starlink 12 by SpaceX, is actually the 13th big batch of satellites the company has shot into space. However, the company has been systematically de-orbiting its initial batch of 60 satellites that were launched in May 2019. That’s because SpaceX always meant for that initial bunch to be a test series. Thus far, 26 of the original satellites have been deorbited, eight are in decaying orbits, and 26 are operational.
SpaceX hopes to provide high-speed internet access to users around the world through the Starlink megaconstellation. By using a small terminal (no larger than a laptop), users on the ground will be able to connect to the ever-growing network. SpaceX founder and CEO Elon Musk has said that the company needs to launch between 500 and 800 satellites in order to begin rolling out service.
To date, SpaceX has launched more than 700 of the internet-beaming satellites into orbit, in an effort to fill out its planned initial constellation of 1,440 spacecraft. SpaceX has already begun speed-testing its space-based internet service, and the initial data looks promising. Company engineers have said that data collected so far indicates that the service will provide fast download speeds, allowing users to stream multiple HD movies at the same time.
The Starlink broadband internet is in a private beta-testing phase now, but it will be available for the public to start beta-testing later this year, SpaceX representatives have said.
Related: SpaceX launches 60 Starlink satellites and lands rocket in dazzling nighttime liftoff
Today's launch marks the 94st flight overall for SpaceX’s workhorse two-stage Falcon 9 rocket. The liftoff is expected to feature a veteran Falcon 9 first stage, designated B1058, that has two flights under its belt. This frequent flyer previously launched two NASA astronauts on a trip to the space station as well as a communications satellite for the South Korean military.
Flying previously flown boosters has become commonplace for SpaceX, as the company continues to prove the Falcon 9's reliability. SpaceX is both the launch provider as well as the customer for its Starlink missions, and as such has kept up a rapid launch pace this summer, relying heavily on its fleet of flight-proven boosters.
In fact, this mission marks the 17th flight of 2020 for SpaceX, with Falcon 9 earning the title of most-flown American rocket earlier this year — a superlative it snagged from a chief competitor, United Launch Alliance's Atlas V.
To date, SpaceX has successfully landed its first-stage boosters 60 times. Now that the company has two fully operational drone-ship landing platforms — "Of Course I Still Love You" and "Just Read the Instructions" — in Florida, it’s able to launch (and land) more rockets. The newer drone ship on the block, "Just Read the Instructions," is already at the recovery zone waiting for its turn to catch B1058 when it returns to Earth this afternoon.
Related: Why SpaceX's Starlink satellites caught astronomers off guard
This is SpaceX's second attempt to get this mission off the ground. The previous attempt on Sept. 17, was called off due to poor weather conditions at the recovery zone.
Activity in the Atlantic Ocean is very busy this year, with several storm systems developing. One such system, Hurricane Paulette, has been keeping the seas churned up so that the drone ship “Just Read the Instructions” could not stabilize itself enough to catch the returning booster. So SpaceX decided to stand down from its original launch attempt and wait for calmer seas.
The delay worked in SpaceX's favor as it brought fairer weather and calmer seas. Forecasters at the 45th Weather Squadron predicted a 70% chance of favorable launch conditions today. The only issue was the possible development of cumulus clouds.
SpaceX will continue its tradition of recovering the Falcon 9's payload fairing, or nose cone, on today's flight. The company has already deployed its twin net-equipped boats — called GO Ms. Tree and GO Ms. Chief — to snag the fairing halves as they fall back to Earth in two pieces.
Each piece of the clamshell-like hardware, which cost approximately $6 million combined, is outfitted with software that navigates it to the recovery zone, and a parachute system that lets them gently land in the ocean or the outstretched net of GO Ms. Tree and GO Ms. Chief.
One of the pieces of the fairing on this mission has flown twice already, protecting two different Starlink payloads — one in May 2019 and one in March 2020.
Editor's note: This story, originally posted Sept. 17, has been updated for SpaceX's new launch date of Sept. 28.
Follow Amy Thompson on Twitter @astrogingersnap. Follow us on Twitter @Spacedotcom or Facebook.


livescience--2020-09-29--1 million people have now died from COVID-19 worldwide

At least 1 million people have now died from COVID-19 .
This grim milestone comes eight months after the public first learned that a mysterious respiratory virus was infecting people in China .
The novel coronavirus swept quickly across the globe and overwhelmed hospitals from Italy to New York City .
The virus has caused a larger death toll in some places than in others ; the toll is highest in the U.S. with more than 204,900 deaths , followed by more than 141,700 deaths in Brazil and more than 95,500 deaths in India , according to the Johns Hopkins @ @ @ @ @ @ @ likely lower than the actual death toll of the virus , Dr. Mike Ryan , the executive director of the World Health Organization 's health emergencies program said on Monday ( Sept. 28 ) .
`` When you count anything , you ca n't count it perfectly but I can assure you that the current numbers are likely an underestimate of the true toll of COVID , '' he said .
On Friday ( Sept. 25 ) , Ryan said it 's possible the death toll could double to 2 million before vaccines @ @ @ @ @ @ @ do n't work to stop the spread .
`` It 's certainly unimaginable , but it 's not impossible , because if we look at losing 1 million people in nine months and then we just look at the realities of getting vaccines out there in the next nine months , it 's a big task for everyone involved , '' he said , according to CNBC .
`` The real question is : Are we prepared , collectively , to do what it takes to avoid that number ? ''
Still , @ @ @ @ @ @ @ because experts have started to understand how best to treat severe patients , for instance figuring out how to best deliver oxygen and giving the steroid dexamethasone , Ryan said , according to CNBC .
In the U.S. , COVID-19 is on track to become the third-leading cause of death in 2020 , after heart disease and cancer , Live Science previously reported .
The Institute for Health Metrics and Evaluation ( IHME ) model predicts that nearly 167,000 more people will die in the U.S. by January 2021 .
Worldwide , at @ @ @ @ @ @ @ novel coronavirus , and more than 7.1 million of those cases come from the U.S. , according to the Johns Hopkins dashboard .

At least 1 million people have now died from COVID-19. This grim milestone comes over eight months after the public first learned that a mysterious respiratory virus was infecting people in China.
The novel coronavirus swept quickly across the globe and overwhelmed hospitals from Italy to New York City. The virus has caused a larger death toll in some places than in others; the toll is highest in the U.S. with more than 204,900 deaths, followed by more than 141,700 deaths in Brazil and more than 95,500 deaths in India, according to the Johns Hopkins dashboard.
Related: Coronavirus live updates
But the official tally is likely lower than the actual death toll of the virus, Dr. Mike Ryan, the executive director of the World Health Organization's health emergencies program said on Monday (Sept. 28). "When you count anything, you can't count it perfectly but I can assure you that the current numbers are likely an underestimate of the true toll of COVID," he said.
On Friday (Sept. 25), Ryan said it's possible the death toll could double to 2 million before vaccines become available, at least if countries don't work to stop the spread.
"It's certainly unimaginable, but it's not impossible, because if we look at losing 1 million people in nine months and then we just look at the realities of getting vaccines out there in the next nine months, it's a big task for everyone involved," he said, according to CNBC. "The real question is: Are we prepared, collectively, to do what it takes to avoid that number?"
Still, fatality rates have slowly declined over time because experts have started to understand how best to treat severe patients, for instance figuring out how to best deliver oxygen and giving the steroid dexamethasone, Ryan said, according to CNBC.
In the U.S., COVID-19 is on track to become the third-leading cause of death in 2020, after heart disease and cancer, Live Science previously reported. The Institute for Health Metrics and Evaluation (IHME) model predicts that nearly 167,000 more people will die in the U.S. by January 2021. Worldwide, at least 33.2 million people have contracted the novel coronavirus, and more than 7.1 million of those cases come from the U.S., according to the Johns Hopkins dashboard.
Originally published on Live Science.


livescience--2020-09-28--Trump administration plans to distribute 100 million rapid COVID-19 tests to states

The Trump administration has announced a plan to distribute millions of rapid COVID-19 tests to states , with a focus on using the tests to reopen schools .
On Monday ( Sept. 28 ) , President Donald Trump said in a news conference that the federal government would soon begin deploying 150 million rapid COVID-19 tests across the country .
Of these , 50 million tests would go to support `` vulnerable communities , '' such as those in nursing homes , while 100 million tests would go to states `` to support efforts to reopen their economies and schools @ @ @ @ @ @ @ '' Trump said .
The rapid test , which is made by Abbott , is an antigen test , which looks for specific viral proteins , and can provide results in 15 minutes .
Known as the Abbott BinaxNOW COVID-19 Ag Card , the test is a simple nasal swab that requires no lab equipment .
The test received emergency use authorization from the U.S. Food and Drug Administration in late August , .
The test is authorized for use in point-of-care settings , that is , at the time patients receive care @ @ @ @ @ @ @ $ 760 million contract to Abbott for delivery of its rapid tests , according to a statement from the .
To start , 6.5 million tests will be shipped to states this week .
Although governors will be allowed to use the tests as they see fit , they are encouraged to use them in schools , officials said .
`` We expressed a hope to all the governors today that they would particularly use these Abbott Binax tests to open up American 's schools and to keep them open , '' Vice @ @ @ @ @ @ @ .
There are about 56 million school-aged children in the United States , and 3.7 million teachers , according to the .
Trump specifically mentioned using the tests for teachers , saying the testing efforts would `` allow every state to , on a very regular basis , test every teacher who needs it . ''

The Trump administration has announced a plan to distribute millions of rapid COVID-19 tests to states, with a focus on using the tests to reopen schools.
On Monday (Sept. 28), President Donald Trump said in a news conference that the federal government would soon begin deploying 150 million rapid COVID-19 tests across the country. Of these, 50 million tests would go to support "vulnerable communities," such as those in nursing homes, while 100 million tests would go to states "to support efforts to reopen their economies and schools immediately and fast as they can," Trump said.
The rapid test, which is made by Abbott, is an antigen test, which looks for specific viral proteins, and can provide results in 15 minutes. Known as the Abbott BinaxNOW COVID-19 Ag Card, the test is a simple nasal swab that requires no lab equipment. The test received emergency use authorization from the U.S. Food and Drug Administration in late August, Live Science previously reported . The test is authorized for use in point-of-care settings, that is, at the time patients receive care. The Trump administration recently awarded a $760 million contract to Abbott for delivery of its rapid tests, according to a statement from the U.S. Department of Health & Human Services .
To start, 6.5 million tests will be shipped to states this week. Although governors will be allowed to use the tests as they see fit, they are encouraged to use them in schools, officials said.
"We expressed a hope to all the governors today that they would particularly use these Abbott Binax tests to open up American's schools and to keep them open," Vice President Mike Pence said at the conference.
There are about 56 million school-aged children in the United States, and 3.7 million teachers, according to the National Center for Educational Statistics . Trump specifically mentioned using the tests for teachers, saying the testing efforts would "allow every state to, on a very regular basis, test every teacher who needs it."
Originally published on Live Science.