livescience--2020-12-26--Mysterious asteroid the size of a dwarf planet is lurking in our solar system

There 's a giant asteroid somewhere out in the , and it hurled a big rock at .
The evidence for this mystery space rock comes from a diamond-studded meteor that exploded over Sudan in 2008 .
NASA had spotted the 9-ton ( 8,200 kilograms ) , 13-foot ( 4 meters ) heading toward the planet well before impact , and researchers showed up in the Sudanese desert to collect an unusually rich haul of remains .
Now , a new study of one of those meteorites suggests that the meteor may have broken off of a giant asteroid — @ @ @ @ @ @ @ the dwarf planet Ceres , the largest object in the asteroid belt .
Related : 6 reasons astrobiologists are holding out hope for life on Mars Like about 4.6 % of meteorites on Earth , this one — known as Almahata Sitta ( AhS ) — is made of a material known as carbonaceous chondrite .
These black rocks contain organic compounds as well as a variety of minerals and water .
The mineral makeup of these space rocks offers clues about the `` parent asteroid '' that birthed a given meteor , @ @ @ @ @ @ @ dominated by minerals providing evidence for exposure to water at low temperatures and pressures , '' study co-author Vicky Hamilton , a planetary geologist at the Southwest Research Institute in Boulder , Colorado , said in the statement .
`` The composition of other meteorites points to heating in the absence of water . ''
The team analyzed a teensy 0.0018-ounce ( 50 milligrams ) sample of AhS under a microscope and found it had a unique mineral makeup .
The meteorite harbored an unusual suite of minerals that form at `` intermediate @ @ @ @ @ @ @ what you 'd find in a typical asteroid , but lower than the inside of a planet ) .
One mineral in particular , amphibole also requires prolonged exposure to water to develop .
Amphibole is common enough on Earth , but it 's only appeared once before in trace amounts in a meteorite known as Allende — the largest carbonaceous chondrite ever found , which fell in Chihuahua , Mexico , in 1969 The high amphibole content of AhS suggests the fragment broke off a parent asteroid that 's never left meteorites @ @ @ @ @ @ @ back from the asteroids Ryugu and Bennu by Japan ’ s Hayabusa2 and NASA ’ s OSIRIS-REx probes , respectively , will likely reveal more space rock minerals that rarely turn up in meteorites , the researchers wrote in their study .
Maybe some types of carbonaceous chondrite just do n't survive the plunge through the atmosphere as well , Hamilton said , and that 's kept scientists from studying a flavor of chondrite that might be more common in space .
`` We think that there are more carbonaceous chondrite materials in @ @ @ @ @ @ @ our collections of meteorites , '' she said .
The paper was published Dec. 21 in the journal .

There's a giant asteroid somewhere out in the solar system , and it hurled a big rock at Earth .
The evidence for this mystery space rock comes from a diamond-studded meteor that exploded over Sudan in 2008.
NASA had spotted the 9-ton (8,200 kilograms), 13-foot (4 meters) meteor heading toward the planet well before impact, and researchers showed up in the Sudanese desert to collect an unusually rich haul of remains. Now, a new study of one of those meteorites suggests that the meteor may have broken off of a giant asteroid — one more or less the size of the dwarf planet Ceres, the largest object in the asteroid belt.
Related: 6 reasons astrobiologists are holding out hope for life on Mars
Like about 4.6% of meteorites on Earth, this one — known as Almahata Sitta (AhS) — is made of a material known as carbonaceous chondrite. These black rocks contain organic compounds as well as a variety of minerals and water.
The mineral makeup of these space rocks offers clues about the "parent asteroid" that birthed a given meteor, researchers said in a statement .
"Some of these meteorites are dominated by minerals providing evidence for exposure to water at low temperatures and pressures," study co-author Vicky Hamilton, a planetary geologist at the Southwest Research Institute in Boulder, Colorado, said in the statement. "The composition of other meteorites points to heating in the absence of water."
The team analyzed a teensy 0.0018-ounce (50 milligrams) sample of AhS under a microscope and found it had a unique mineral makeup.
The meteorite harbored an unusual suite of minerals that form at "intermediate" temperatures and pressures (higher than what you'd find in a typical asteroid, but lower than the inside of a planet). One mineral in particular, amphibole also requires prolonged exposure to water to develop.
Amphibole is common enough on Earth, but it's only appeared once before in trace amounts in a meteorite known as Allende — the largest carbonaceous chondrite ever found, which fell in Chihuahua, Mexico, in 1969
The high amphibole content of AhS suggests the fragment broke off a parent asteroid that's never left meteorites on Earth before.
And samples brought back from the asteroids Ryugu and Bennu by Japan’s Hayabusa2 and NASA’s OSIRIS-REx probes, respectively, will likely reveal more space rock minerals that rarely turn up in meteorites, the researchers wrote in their study.
Maybe some types of carbonaceous chondrite just don't survive the plunge through the atmosphere as well, Hamilton said, and that's kept scientists from studying a flavor of chondrite that might be more common in space.
"We think that there are more carbonaceous chondrite materials in the solar system than are represented by our collections of meteorites," she said.
The paper was published Dec. 21 in the journal Nature Astronomy .
Originally published on Live Science.


livescience--2020-12-27--10 times science made a sucky year suck less

With a novel coronavirus devastating the world since the spring , the year 2020 has been difficult .
Still , even in these hard times , some moments of joy crept through — and some of them were sparked by awe-inspiring scientific discoveries and phenomena .
From the incredible efforts of scientists to develop a COVID-19 vaccine in record time to clapping seals and swimming dinosaurs , here are 10 ways that science made a sucky year suck less .
This year , scientists across the globe undertook a massive and unprecedented effort to develop vaccines to fight the novel @ @ @ @ @ @ @ unprecedented timescales .
Less than a year after the mysterious cluster of pneumonia-like illnesses in Wuhan , China were identified , scientists have developed 223 candidate coronavirus vaccines to fight the virus that caused it ; 57 of these vaccines are already being tested on humans , according to the WHO .
Two of the vaccines are already being deployed in the U.S. ; those harness a relatively new technology based on a synthetic strand of genetic code called messenger RNA that primes the immune system to fight the novel coronavirus .
The @ @ @ @ @ @ @ , are 95 % and 94.1 % effective , respectively .
What 's more , experts say this technology could be a game changer for vaccine development in the future .
[ Read more about the incredible accomplishments and ] Almost 100 years after critically endangered blue whales nearly went extinct due to industrial whaling , they have returned to the waters of South Georgia island near Antarctica .
Only a single blue whale had been sighted between 1998 and 2018 in this area , which was once a center for industrial whaling @ @ @ @ @ @ @ 1960s ; about 42,000 blue whales were killed around South Georgia between 1904 and 1971 .
But a recent survey came back with some very hopeful news : Scientists aboard a research ship in January and February of 2020 , counted dozens of blue whales that had returned to the area .
In total , they detected 58 individual blue whales , according to a study published Nov. 19 in the journal .
`` We 've had indications in previous years that there might be more blue whales starting to come back to @ @ @ @ @ @ @ Susannah Calderan told Live Science .
`` But we were very favorably surprised by quite how many we did see this year . ''
[ Read more about the return of this endangered creature ] Scientists have detected a mysterious , unexplained chemical in the upper atmosphere of Venus , and suggested that it could be a sign of life .
The chemical , a phosphine gas ( PH3 ) , is made on our planet by bacteria and by `` anthropogenic activity , '' or activities that humans are doing .
Phosphine @ @ @ @ @ @ @ giant planets due to known chemical processes .
But no such chemical process is known to exist on Venus .
Still , do n't go looking for E.T .
on Venus just yet , as phosphine could have been made by a chemical process that 's just unknown to us , the researchers wrote on Sept. 14 in the journal .
[ Read more about life on Venus ] For the first time , a seal was recorded clapping ( or slapping its flippers together ) in the wild , unprompted by training @ @ @ @ @ @ @ a study published in the journal in January .
This particularly entertaining creature was male gray seal swimming ( and clapping ) near the Farne Islands in northeast England .
Only male seals appear to clap , and they tend to do so when other seals are nearby ; this clapping seal was swimming near a female and a male seal .
So biologists are guessing that the gray seals either clap to get mates or to shoo away competitors .
[ Read more about this clapping seal ] Dinosaurs were not thought @ @ @ @ @ @ @ this year when researchers discovered a paddle-like tail in southeastern Morocco that belonged to a predatory , sharp-toothed dinosaur called Spinosaurus aegyptiacus .
This new tail , which was tall and flat like a fin , is reminiscent of the ones found in modern crocodiles , the researchers reported in April in the journal .
Still , researchers say that because the fossils were found inland , this dinosaur was likely more comfortable on land and just swam in shallow waters , without straying too far .
[ Read more about these water @ @ @ @ @ @ @ scent in their wrist glands , rub it on their tails and waft a scent cloud towards a potential mate .
Male lemurs commonly use such secretions to communicate with other males to mark their territory , demonstrate social rank or announce that they 're ready to breed .
But scientists recently discovered that they also use these chemicals to `` stink flirt '' with females .
Typically , secretions from the wrist glands smell `` bitter , '' `` leathery '' and `` green , '' but during breeding season they smell @ @ @ @ @ @ @ , '' the authors wrote in a paper published in April in the journal .
This might mark the first evidence of sex pheromones in primates .
On Dec. 21 , Jupiter and Saturn appeared so close together in the night sky that they looked like one star .
This rare phenomenon , called the `` Great Conjunction , '' occurs every 20 years but the two gas giants have n't been this close to each other since July 16 , 1623 , when the famous astronomer Galileo Galilei was alive .
The @ @ @ @ @ @ @ appeared so close together , was in 1223 .
[ Read more about this rare phenomenon ] A grey parrot named Griffin has outsmarted 21 Harvard students in a classic memory game , according to a study published in May in the journal .
African grey parrots ( Psittacus erithacus ) can live for more than 50 years and were always known to be impressive ; they can memorize dozens of words , after all .
But now Griffin has shown that impressive is an understatement .
Researchers gave Griffin and the Harvard @ @ @ @ @ @ @ had to find a colorful pom-pom under a plastic cup after it was shuffled around the table several times .
Griffin did as well or better than the students in 12 out of 14 trials .
To locate the pompom both Griffin and the students were using a feature of their working memories called `` manipulation , '' which based on Griffin 's amazing performance , may be an evolutionarily ancient capability , according to the researchers .
A recently discovered 9,000-year-old burial of a female hunter , and other analyses of hunter @ @ @ @ @ @ @ in the ancient Americas hunted big game just as much as men did .
These findings suggest that the accepted story of ancient men hunting big game while women gathered herbs and plants is not always true .
`` These findings sort of underscore the idea that the gender roles that we take for granted in society today — or that many take for granted — may not be as natural as some may have thought , '' lead author Randy Haas , an assistant professor of anthropology at the University of California @ @ @ @ @ @ @ The team identified 429 skeletons from different ancient burial sites across the Americas ; 27 of the skeletons were buried with big-game hunting tools .
Among those buried with big-game hunting tools , 11 were female ( including the newly discovered female ) and 15 were male , according to a study published on Nov. 4 in the journal .
Further statistical analysis suggested that between 30 % and 50 % of hunters in these populations were female .
`` What we see is that female and male burials are just as likely @ @ @ @ @ @ @ , '' Haas said .
[ Read more about these fierce female hunters ] Another strange tale of 2020 : octopuses sometimes punch fish , because why not ?
Big blue octopuses ( Octopus cyanea ) sometimes work with fish in order to find food .
But sometimes when they 're displeased with those fish , or do n't want to share the jointly-hunted food , they use a `` swift , explosive motion with one arm , '' in other words , punch them in the head , according to a new @ @ @ @ @ @ @ .
`` I laughed out loud , and almost choked on my own regulator , '' lead study author Eduardo Sampaio , a Ph.D. student at the University of Lisbon and the Max Planck Institute of Animal Behavior , told Live Science in an email .
His later reactions were more subdued , `` but I still marveled at it every time I saw it , '' he added .
The researchers observed this behavior eight times between 2018 and 2019 while diving in Eilat , Israel , and in El Quseir , @ @

We could be 16 years into a methane-fueled 'termination' event significant enough to end an ice age
Methane emissions from tropical wetlands have been soaring since 2006 and accelerating at the same breakneck speed as when Earth's climate has flipped from a glacial to an interglacial period.


livescience--2020-12-27--What are the most common ways people get injured?

Every year in the United States , 40 million people end up injured in the emergency department , according to the .
From bee stings to car accidents , health care workers in emergency departments see it all .
So , what are the most common ways people get injured ?
`` Falls by far , '' said Susan Baker , an epidemiologist specializing in injury prevention at Johns Hopkins Bloomberg School of Public Health , `` Especially when you 're talking about non-fatal injuries . ''
In 2018 , about 29 % of percent of people who went to @ @ @ @ @ @ @ had fallen down , according to the CDC .
The most common culprit ?
Likely stairs , according to the ( NEISS ) , a database of consumer product-related injuries .
( The database lists stairs alongside ramps and landings . )
Stair-related injuries are a risk for older adults in particular , who tend to fall more often than younger people due to cognitive decline and loss of physical fitness .
`` If you do n't stay physically fit , you start to lose some of your balance , '' said Lorann @ @ @ @ @ @ @ Injury Control Research Center .
Related : Why does spinning make you dizzy ?
Babies and toddlers are also particularly vulnerable to falling and getting injured as they explore their environment and learn to walk , Stallones told Live Science .
In a 2012 study of 285 babies and toddlers published in the , stairs were the most common reason kids fell , followed by rolling out of bed , tumbling out of shopping carts or being dropped by a caretaker .
Other causes of injury vary substantially across age groups .
`` @ @ @ @ @ @ @ Stallones said .
For example , in children age 5 and older , it 's playing that gets them hurt .
Playgrounds , pools , trampolines and sports are just some of the most common causes of injury in this group — more common even than injuries related to stairs , according to the NEISS database .
For example , in 2018 , bicycle accidents sent more kids ages 5 to 14 to the emergency department than they did to any other age group , according to the .
Each year , a @ @ @ @ @ @ @ ( those ages 15 to 24 ) get injured while playing sports .
Basketball and football are listed as the most common causes of injury for this age group , aside from stairs , according to the NEISS database .
In middle age , exercise equipment ranks high up there .
And according to a 2005 study published in the journal , the majority of adults who received medical attention for a fall injured themselves while exercising .
That 's not to say we should stop playing or exercising , said Steve Mooney @ @ @ @ @ @ @ Prevention & Research Center in Seattle , Washington .
`` Sports can be really fun for people and they can provide physical activity .
There 's lots of benefits , '' Mooney told Live Science .
The same goes for many of our other day-to-day activities that carry risk of injury , such as riding a bike to work and climbing stairs .
`` It does n't mean we should n't do it , it 's just that there 's risk associated with it , '' Mooney said .

Every year in the United States, 40 million people end up injured in the emergency department, according to the Centers for Disease Control and Prevention (CDC) . From bee stings to car accidents, health care workers in emergency departments see it all. So, what are the most common ways people get injured?
"Falls by far," said Susan Baker, an epidemiologist specializing in injury prevention at Johns Hopkins Bloomberg School of Public Health, "Especially when you're talking about non-fatal injuries." In 2018, about 29% of percent of people who went to the emergency department because of an injury had fallen down, according to the CDC . The most common culprit? Likely stairs, according to the National Electronic Injury Surveillance System (NEISS), a database of consumer product-related injuries. (The database lists stairs alongside ramps and landings.)
Stair-related injuries are a risk for older adults in particular, who tend to fall more often than younger people due to cognitive decline and loss of physical fitness. "If you don't stay physically fit, you start to lose some of your balance," said Lorann Stallones, the director of the Colorado Injury Control Research Center.
Related: Why does spinning make you dizzy?
Babies and toddlers are also particularly vulnerable to falling and getting injured as they explore their environment and learn to walk, Stallones told Live Science. In a 2012 study of 285 babies and toddlers published in the International Journal of Developmental Neuroscience , stairs were the most common reason kids fell, followed by rolling out of bed, tumbling out of shopping carts or being dropped by a caretaker.
Other causes of injury vary substantially across age groups. "So much depends on age," Stallones said. For example, in children age 5 and older, it's playing that gets them hurt. Playgrounds, pools, trampolines and sports are just some of the most common causes of injury in this group — more common even than injuries related to stairs, according to the NEISS database. For example, in 2018, bicycle accidents sent more kids ages 5 to 14 to the emergency department than they did to any other age group, according to the CDC .
Each year, a large number of teens and young adults (those ages 15 to 24) get injured while playing sports. Basketball and football are listed as the most common causes of injury for this age group, aside from stairs, according to the NEISS database. In middle age, exercise equipment ranks high up there. And according to a 2005 study published in the journal BMC Public Health , the majority of adults who received medical attention for a fall injured themselves while exercising.
That's not to say we should stop playing or exercising, said Steve Mooney, an epidemiologist at the Harborview Injury Prevention & Research Center in Seattle, Washington. "Sports can be really fun for people and they can provide physical activity. There's lots of benefits," Mooney told Live Science. The same goes for many of our other day-to-day activities that carry risk of injury, such as riding a bike to work and climbing stairs. "It doesn't mean we shouldn't do it, it's just that there's risk associated with it," Mooney said.


livescience--2020-12-27--10 times sharks made our jaws drop in 2020

Sharks will never stop amazing us — from mysterious and massive whale sharks to intimidating and impressive great whites .
Even sharks that do n't exist anymore , like the mammoth megalodon , never cease to astonish .
We know you love sharks just as much as we do , so here are 10 awesome things we learned about sharks this year .
Who knew sharks could dance ?
OK , well , these sharks were n't actually dancing , but they were certainly busting some kind of move .
A group of 20 tawny sharks were caught on video @ @ @ @ @ @ @ on a beach in Australia .
The sharks were n't in distress ; they were simply using their bodies to stir up some tasty clams known as pipis ( Paphies australis , the name `` pipi '' comes from the Māori language ) , which were buried in the wet sand .
Read more : Why are these sharks doing the 'pipi ' dance ?
Whale sharks are the largest fish in the sea , but there 's still a lot scientists do n't know about the enormous creatures , including how long @ @ @ @ @ @ @ this year described how radioactive carbon left over from Cold War-era nukes could help resolve this mystery .
Researchers dated carbon-14 — a naturally-occurring type of radioactive carbon that was released into the sky en masse during nuclear weapons tests in the 1950s and 1960s — embedded in the vertebrae of two whale sharks that died long ago in fishing nets in Taiwan and Pakistan .
The scientists confirmed the ages of the two dead sharks were 35 and 50 years old , respectively , which fits in with prior estimates that whale @ @ @ @ @ @ @ likely upwards of 100 years .
Read more : Nuclear bombs could reveal how old whale sharks really are 3 .
Great white sharks are bottom-feeders ( for at least part of their lives ) Great white sharks are vicious hunters — except when they 're not .
After studying the stomach contents of 40 white sharks in Australia , researchers reported that juvenile white sharks spend a significant amount of time digging around for easy morsels of food on the seafloor rather than hunting for a more hearty meal .
The little @ @ @ @ @ @ @ until the sharks are around 7.2 feet ( 2.2. m ) in length .
There was also some evidence that the male sharks went after stingrays and their cousins more often than female sharks did ; but the researchers noted that there was a fairly small sample size from which to make this claim .
Read more : Great white sharks are bottom-feeders , at least when they 're little A drone captured video of the moment when a white shark was within arm 's reach of a surfer in Australia .
The @ @ @ @ @ @ @ of the shark and only found out how close the 5-foot-long ( 1.6 m ) predator was after swimming to shore and watching the drone footage .
Fortunately , the shark swam away and no one was hurt .
Read more : Drone warns surfer of very close encounter with 5-foot shark in Australia A shark born without skin or teeth was somehow living without trouble until fishers trawling the Mediterranean Sea south of Sardinia , Italy , accidentally pulled the mutant fish from the depths .
The startling creature was a blackmouth @ @ @ @ @ @ @ skin and teeth .
The rare catch is the first and only known case of a shark living with a `` severe lack of all skin-related structures [ including ] teeth , '' according to a study published in the Journal of Fish Biology .
Read more : 'Naked ' shark was born without skin or teeth in world first 6 .
Megalodon was even more of a behemoth than we thought Sure , megalodon was the biggest shark to ever live , but we 're not talking just a few feet longer @ @ @ @ @ @ @ was so massive — about as long as a bowling lane at 50 feet ( 15 m ) — that scientists consider the giant to be `` off the scale , '' according to a new study published this year .
Evidence from extinct and living sharks revealed that not only was megalodon an extreme outlier when compared with modern species ; it was also substantially bigger than the next-biggest extinct shark in its order by at least 23 feet ( 7 m ) , the scientists reported .
Read more : Megalodon @ @ @ @ @ @ @ — even for a shark 7 .
But great whites are still enormous Yes , megalodon was a behemoth , but great white sharks are no pipsqueaks — especially one individual scientists are calling the `` queen of the ocean . ''
Researchers with Ocearch caught and tagged a great white female this year that measured 17 feet ( 5 m ) long and weighed 3,541 lbs .
( 1,606 kilograms ) .
The scientists estimate the shark is around 50 years old , and her battle-scarred hide is clear evidence that this @ @ @ @ @ @ @ lifetime .
Read more : Scientists discover great white shark 'queen of the ocean' Giving the queen a run for her money is another enormous great white shark spotted in Key Largo this fall .
The 15.4-foot-long ( 4.7 m ) shark known as `` Unama'ki '' is also tracked by Ocearch and was first tagged in Nova Scotia .
This big mamma weighs 2,076 lbs .
( 942 kg ) and is also estimated to be about 50 years old .
Although extinct megatooth sharks were monstrous predators , they were also @ @ @ @ @ @ @ in the safety of a `` nursery . ''
Researchers found ancient evidence of a shark nursery in what is now South Carolina .
The team dug up dozens of fossilized teeth that once belonged to Carcharocles angustidens , a megatoothed shark that lived during the Oligocene epoch ( 34 million to 23 million years ago ) .
The size of most of the teeth suggests they came from juvenile sharks , which means the area was probably a safe haven , or nursery , where the young ocean predators could swim in @ @ @ @ @ @ @ Read more : 24 million-year-old nursery for baby megasharks discovered in South Carolina Another group of scientists found fossil evidence of at least five more megalodon nurseries in Spain , which suggests that baby shark nurseries were a common rearing tactic for the species .
It also raises the possibility that the decline of available nursery sites may have contributed to the giant shark 's extinction .
This year , scientists discovered an adorable , wide-eyed prehistoric shark with a hidden set of terrifying chompers .
The previously undescribed species , named Ferromirum @ @ @ @ @ @ @ inward when the mouth was closed , and outward when the mouth was open .
When the shark opened its mouth , cartilage at the back of the jaw flexed so that the sides of the jaw `` folded '' down and all teeth , including the newest teeth growing in the back , rotated upward , allowing the shark to bite into its prey with as many teeth as possible .
Not something you want to see lunging after you in the water , is it ?
Read more : Wide-eyed prehistoric @ @ @ @ @ @ @ jaws 10 .
Even sharks win some , lose some Thresher sharks are aggressive predators , but they ca n't win every fight .
Beachgoers on the Mediterranean coast of Libya found a dead thresher shark with a large chunk of a swordfish 's `` sword '' jabbed into its back .
No one saw the actual attack , so it 's unclear why the swordfish jabbed and killed the shark .
But researchers suspect the two ocean predators may have been competing for prey .
Read more : Whodunit solved when 'sword @ @ @ @ @ @ @ On the other side of the world , undersea photographer Deron Verbeck snapped a remarkable photo of a battle-scarred oceanic whitetip shark ( Carcharhinus longimanusI ) off the coast of Hawaii earlier this year .
The unusual circular pattern of scars and puncture wounds on the shark 's skin led researchers to suspect the shark had been in a fight with a giant squid ( Architeuthis duxI ) — elusive deep-sea predators that live hundreds of feet below the surface .
Oceanic white tip sharks can dive down to 1,000 feet ( 300 @ @ @ @ @ @ @ so it 's likely this shark picked a fight with a deep-sea cephalopod that was not in the mood .
Read more : Mysterious scars on Hawaiian shark could be sign of giant squid attack

Sharks will never stop amazing us — from mysterious and massive whale sharks to intimidating and impressive great whites. Even sharks that don't exist anymore, like the mammoth megalodon, never cease to astonish. We know you love sharks just as much as we do, so here are 20 awesome things we have learned about sharks.
1. Some sharks can get really, really old
(Image credit: dotted zebra / Alamy Stock Photo)
Imagine a shark that was swimming the seas when the Pope excommunicated Martin Luther and the Ming Dynasty was going strong. That might just be the Greenland shark (Somniosus microcephalus), an Arctic dweller that can live centuries — perhaps close to 500 years.
Researchers reported in 2016 in the journal Science that they had tested the eye tissues of these strange sharks and found that they were centuries old. The method wasn't perfectly precise, so the exact age range came to between 271 and 512 years old. Even at the low end, that makes them the longest-lived animal with a backbone. Little is known about the shark's biology or lifestyle.
Read more: Greenland sharks may live 400 years
2. Sharks caught doing the 'pipi' dance
Who knew sharks could dance? OK, well, these sharks weren't actually dancing, but they were certainly busting some kind of move.
A group of 20 tawny sharks were caught on video as they wiggled around in the surf on a beach in Australia. The sharks weren't in distress; they were simply using their bodies to stir up some tasty clams known as pipis (Paphies australis, the name "pipi" comes from the Māori language), which were buried in the wet sand.
Read more: Why are these sharks doing the 'pipi' dance?
3. Nuclear bombs can help age sharks
A whale shark vertebra from Pakistan, in cross section, showing 50 growth bands. (Image credit: Paul Fanning, Pakistan node of the UN Food and Agricultural Organisation)
Whale sharks are the largest fish in the sea, but there's still a lot scientists don't know about the enormous creatures, including how long they live. However, research published this year described how radioactive carbon left over from Cold War-era nukes could help resolve this mystery.
Researchers dated carbon-14 — a naturally-occurring type of radioactive carbon that was released into the sky en masse during nuclear weapons tests in the 1950s and 1960s — embedded in the vertebrae of two whale sharks that died long ago in fishing nets in Taiwan and Pakistan. The scientists confirmed the ages of the two dead sharks were 35 and 50 years old, respectively, which fits in with prior estimates that whale sharks can live incredibly long lives — likely upwards of 100 years.
Read more: Nuclear bombs could reveal how old whale sharks really are
4. Great white sharks are bottom-feeders (for at least part of their lives)
Juvenile great whites spend a good portion of time munching on easy sources of food found on the seafloor. (Image credit: Education Images/Getty Images)
Great white sharks are vicious hunters — except when they're not.
After studying the stomach contents of 40 white sharks in Australia, researchers reported that juvenile white sharks spend a significant amount of time digging around for easy morsels of food on the seafloor rather than hunting for a more hearty meal. The little predators don't start hunting bigger prey until the sharks are around 7.2 feet (2.2. m) in length.
There was also some evidence that the male sharks went after stingrays and their cousins more often than female sharks did; but the researchers noted that there was a fairly small sample size from which to make this claim.
Read more: Great white sharks are bottom-feeders, at least when they're little
5. Shark attacks are (still) rare
A drone caught a close encounter between a surfer and a shark in Australia. (Image credit: Surf Life Saving NSW)
A drone captured video of the moment when a white shark was within arm's reach of a surfer in Australia. The surfer was completely unaware of the proximity of the shark and only found out how close the 5-foot-long (1.6 m) predator was after swimming to shore and watching the drone footage. Fortunately, the shark swam away and no one was hurt.
Read more: Drone warns surfer of very close encounter with 5-foot shark in Australia
6. A 'naked' shark?
A closeup of the skinless shark's body and toothless mouth. (Image credit: Mulas et al.)
A shark born without skin or teeth was somehow living without trouble until fishers trawling the Mediterranean Sea south of Sardinia, Italy, accidentally pulled the mutant fish from the depths. The startling creature was a blackmouth catshark (Galeus melastomus) that lacked skin and teeth.
The rare catch is the first and only known case of a shark living with a "severe lack of all skin-related structures [including] teeth," according to a study published in the Journal of Fish Biology.
Read more: 'Naked' shark was born without skin or teeth in world first
7. Megalodon was even more of a behemoth than we thought
Gigantism was common in extinct lamniform sharks — the group that includes megalodon — but megalodon was the biggest by far. (Image credit: Getty Images/Corey Ford/Stocktrek Images)
Sure, megalodon was the biggest shark to ever live, but we're not talking just a few feet longer than the large great white. Megalodon was so massive — about as long as a bowling lane at 50 feet (15 m) — that scientists consider the giant to be "off the scale," according to a new study published this year.
Evidence from extinct and living sharks revealed that not only was megalodon an extreme outlier when compared with modern species; it was also substantially bigger than the next-biggest extinct shark in its order by at least 23 feet (7 m), the scientists reported.
Read more: Megalodon's hugeness was 'off the scale' — even for a shark
8. But great whites are still enormous
This huge great white shark, named Nukumi, is probably about 50 years old. She was discovered off the coast of Nova Scotia. (Image credit: OCEARCH)
Yes, megalodon was a behemoth, but great white sharks are no pipsqueaks — especially one individual scientists are calling the "queen of the ocean."
Researchers with Ocearch caught and tagged a great white female this year that measured 17 feet (5 m) long and weighed 3,541 lbs. (1,606 kilograms). The scientists estimate the shark is around 50 years old, and her battle-scarred hide is clear evidence that this hefty lady has seen some things her lifetime.
Read more: Scientists discover great white shark 'queen of the ocean'
Giving the queen a run for her money is another enormous great white shark spotted in Key Largo this fall. The 15.4-foot-long (4.7 m) shark known as "Unama'ki" is also tracked by Ocearch and was first tagged in Nova Scotia. This big mamma weighs 2,076 lbs. (942 kg) and is also estimated to be about 50 years old.
Read more: Massive great white shark Unama'ki spotted south of Miami
9. Ancient megatooth sharks were nurturing parents
Megalodon, the biggest predatory shark of all time, watched over its young as many modern sharks do — by raising them in defined geographic areas known as nurseries. (Image credit: Hugo Salais, Metazoa Studio)
Although extinct megatooth sharks were monstrous predators, they were also nurturing parents as they raised their young in the safety of a "nursery."
Researchers found ancient evidence of a shark nursery in what is now South Carolina. The team dug up dozens of fossilized teeth that once belonged to Carcharocles angustidens, a megatoothed shark that lived during the Oligocene epoch (34 million to 23 million years ago). The size of most of the teeth suggests they came from juvenile sharks, which means the area was probably a safe haven, or nursery, where the young ocean predators could swim in calm waters filled with easy-to-catch prey.
Read more: 24 million-year-old nursery for baby megasharks discovered in South Carolina
Another group of scientists found fossil evidence of at least five more megalodon nurseries in Spain, which suggests that baby shark nurseries were a common rearing tactic for the species. It also raises the possibility that the decline of available nursery sites may have contributed to the giant shark's extinction.
Read more: Megalodon nurseries reveal world's largest shark had a soft side
10. An innocent-looking shark with a hidden weapon
Illustration of the prehistoric shark Ferromirum oukherbouchi. (Image credit: Christian Klug, UZH)
This year, scientists discovered an adorable, wide-eyed prehistoric shark with a hidden set of terrifying chompers.
The previously undescribed species, named Ferromirum oukherbouchi, had a jaw that rotated inward when the mouth was closed, and outward when the mouth was open. When the shark opened its mouth, cartilage at the back of the jaw flexed so that the sides of the jaw "folded" down and all teeth, including the newest teeth growing in the back, rotated upward, allowing the shark to bite into its prey with as many teeth as possible.
Not something you want to see lunging after you in the water, is it?
Read more: Wide-eyed prehistoric shark hid its sharpest teeth in nightmare jaws
11. Even sharks win some, lose some
A swordfish (Xiphias gladius) left part of its "sword" sticking out of the shark it killed. (Image credit: The Ichthyological Society of Japan 2020)
Thresher sharks are aggressive predators, but they can't win every fight. Beachgoers on the Mediterranean coast of Libya found a dead thresher shark with a large chunk of a swordfish's "sword" jabbed into its back. No one saw the actual attack, so it's unclear why the swordfish jabbed and killed the shark. But researchers suspect the two ocean predators may have been competing for prey.
Read more: Whodunit solved when 'sword' is found embedded in thresher shark
On the other side of the world, undersea photographer Deron Verbeck snapped a remarkable photo of a battle-scarred oceanic whitetip shark (Carcharhinus longimanusI) off the coast of Hawaii earlier this year. The unusual circular pattern of scars and puncture wounds on the shark's skin led researchers to suspect the shark had been in a fight with a giant squid (Architeuthis duxI) — elusive deep-sea predators that live hundreds of feet below the surface. Oceanic white tip sharks can dive down to 1,000 feet (300 m) in search of prey, so it's likely this shark picked a fight with a deep-sea cephalopod that was not in the mood.
Read more: Mysterious scars on Hawaiian shark could be sign of giant squid attack
12. Shark attacks have a long history
(Image credit: Courtesy of the Laboratory of Physical Anthropology, Kyoto University)
Shark attacks are unusual (only 57 unprovoked bites were reported in 2020), but they're not new. A 3,000-year-old skeleton unearthed in western Japan apparently belonged to the victim of a nasty shark attack.
The skeleton had 790 separate injuries, including many V-shaped notches that match the marks of a shark's teeth on bone. The man was also missing his left hand and right leg when he was buried, and his left leg was arranged in his grave the wrong way around. The damage suggests that the man was alive when he was attacked and that sharks had time to feed on his body for at least a while before he was retrieved from the sea.
Read more: Oldest-known shark attack discovered in 3,000-year-old skeleton with 800 injuries
13. Sharks nearly wiped out 19 million years ago
(Image credit: Leah D. Rubin)
Sharks have been trolling the oceans for an incredibly long time: They evolved at least 450 million years ago, making them older, as a group, than trees.
You don't get through 450 million years without some rough patches. And research published in 2021 found that about 19 million years ago, the world nearly said goodbye to sharks. In just 100,000 years or less, 90% of sharks disappeared from the oceans. Between 70% and 90% of shark species were lost. No one knows what happened or why sharks suddenly faced such a struggle.
Read more: Mysterious event nearly wiped out sharks 19 million years ago
Originally published on Live Science.
14. Some sharks are pocket-size
(Image credit: Mark Doosey)
OK, everyone knows that not every shark is a behemoth. But did you know that sharks can be pocket-size and absolutely adorable?
The pocket shark Mollisquama mississippiensis was declared a new species in 2019 after originally being discovered in the Gulf of Mexico in 2015. The tiny shark —it's only 5.5 inches (14 cm) long — looks a bit like a miniature sperm whale, with a blunt, rounded nose. Only two pocket sharks have ever been caught, raising questions about how many more small, quiet shark species call the Gulf of Mexico home.
Read more: Adorable Shark Fits in Your Hand, Looks Like a Mini Sperm Whale
15. Ancient sharks were really strange
(Image credit: Oscar Sanisidro)
A Cretaceous shark that lived 93 million years ago acted more like a manta ray than a shark. Aquilolamna milarcae existed before manta rays evolved, but it had wide, swooping fins that looked almost like wings. Researchers who identified the fossils from quarry rock found in Mexico think the ancient shark was a plankton-eating filter-feeder that cruised at a stately pace through the Western Interior Seaway, a body of water that once covered much of what is now Mexico and the middle of North America.
The shark still remains a bit of an evolutionary mystery, because none of its teeth were preserved. That makes it difficult to place the species within the tree of shark diversity. This strange shark likely went extinct at the end of the Cretaceous when an enormous asteroid slammed into what is now the Yucatán Peninsula.
Read more: 'Winged' eagle shark soared through the oceans 93 million years ago
16. Sharks eat their siblings … in the womb
A series of ultrasound images shows a shark embryo swimming from one uterus to another. (Image credit: Ethology)
It's not easy being a baby shark. For one thing, your siblings will try to eat you.
Biologists have known for decades that shark fetuses will cannibalize each other in the womb — no brotherly love here. Shark mothers can store up sperm from multiple mating events and fertilize their eggs over time, so they frequently have a womb full of half-siblings. In sand tiger sharks (Carcharias taurus), the babies of one father tend to dominate those from another father over time, a way that males apparently compete to father the most offspring well after mating occurs.
Baby sharks will even swim from one uterus to another (sharks have two uteruses) in search of a meal. A 2018 study found that tawny nurse shark babies wiggle between uteruses and sometimes even poke their heads out of their mother's cervix before they're ready to be born.
Read more: These Baby Sharks Swim from One Uterus to Another to Eat Their Unfertilized Siblings
17. Shark gets stabbed to death
(Image credit: Arturo Chacon/Tag Cabo Sportfishing)
Not often do humans get a glimpse at a shark battle, especially one where the top predator ends up with a sword in its head. That's exactly what beachgoers witnessed in February of 2021 when a juvenile shortfin mako shark (Isurus oxyrinchus) washed up in Los Cabos, Mexico. The "sword" was still embedded in the dead shark's head. But who or what was the culprit? After examining images of the stabbed mako, Christopher Lowe, a professor of marine biology and director of the Shark Lab at California State University, Long Beach, said the sword could have come from a marlin, sailfish or stingray.
One likely scenario goes like this: Scientists know that adult makos prey on animals with "swords." And perhaps, this juvenile shark tried to nab such a meal but was unsuccessful. "This one was a young one — probably inexperienced and trying to take on prey that it wasn't really ready for," Lowe previously told Live Science.
Read more: Shark gets stabbed in the head, washes ashore in Los Cabos
18. Feeding frenzy ends badly for this shark
(Image credit: NOAA Office of Ocean Exploration and Research, Windows to the Deep 2019)
An ocean feeding frenzy turned deadly for one of the diners some 1,476 feet (450 meters) below the surface of the Atlantic Ocean in June 2019. About 11 dogfish sharks were devouring a 250-pound (110 kilograms) corpse of a swordfish. Little did they know, a wreckfish, which is a type of grouper, was waiting in the wings for its own supper. While the sharks were distracted, filling their bellies, it seems the giant wreckfish swooped in and gulped one down.
Post-meal, the wreckfish — with the shark’s tail sticking out of its mouth — inched in front of a camera on a remote rover called Deep Discoverer. The remotely operated vehicle was in the area searching for a World War II shipwreck; when the scientists saw the footage, one of them is heard saying: "Oh my god — I'm going to remember this my whole life."
Read more: Feeding frenzy of 11 sharks ends in surprising twist
19. Great white sharks have some serious pregnancies
Female great white shark swimming with a school of trevally jacks surrounding it's tail, North Neptune Islands, South Australia. (Image credit: by wildestanimal via Getty Images)
Fourteen bouncing baby white sharks. That's what one mama great white was expecting when she was accidentally caught near Taiwan in 2018.
The 15-foot-long (14.7 meters) shark was a record-breaker. Detecting pregnant sharks is rare, and the previous known record for a pregnant great white (Carcharodon carcharias) was 12 pups, David Ebert, a shark scientist and the director of the Pacific Shark Research Center at Moss Landing Marine Laboratories in Moss Landing, California, told Live Science at the time.
Great white shark pregnancy and gestation are still quite mysterious, but pups probably take about 12 months to develop and are born alive and ready to start hunting.
Read more: Enormous great white shark pregnant with record 14 pups was caught and sold in Taiwan
20. Sharks can choke to death
(Image credit: wildestanimal/Shutterstock)
In the battle of great white shark versus turtle, the turtles usually win. Sea turtle shells are strong protection against even great white sharks, and sea turtles know to turn sideways when approached by a white shark so it's harder for the predator to get a grip on them. In one incident witnessed by a Japanese fisherman in 2019, though, a shark managed to get a purchase — but the turtle got its revenge. After getting the turtle lodged in its throat, the shark choked and died.
Read more: Great white shark chomps down on sea turtle, chokes to death
Editor's note: This article was first published in 2020 and updated by Stephanie Pappas on July 7, 2021.
Originally published on Live Science.


livescience--2020-12-27--World's largest iceberg continues to break up off the coast of South Georgia

The world 's ( former ) largest iceberg continues to break apart into smaller pieces on the doorstep of a major marine wildlife haven and home to millions of macaroni and king in Antarctica .
This comes less than a week after the mammoth iceberg , known as A68a , first split in two , .
Scientists at the U.S. National Ice Center ( USNIC ) spotted the two newest pieces , A68e and A68f , on Dec. 22 using images from the Sentinel-1A satellite , according to a .
This means that there are now four separate iceberg fragments @ @ @ @ @ @ @ drift away from one another .
A68a became the world 's largest iceberg when it split from 's Larsen C ice shelf in July 2017 , .
The massive chunk of ice has been drifting northward ever since .
As recently as April , it measured 2,000 square miles ( 5,100 square kilometers ) , or just over the size of the state of Delaware .
Related : In photos : Antarctica 's Larsen C ice shelf through time In the spring of 2020 , A-68a set its sights on South Georgia Island @ @ @ @ @ @ @ Atlantic Ocean that 's home to millions of penguins , seals and other marine wildlife .
Experts feared that if it were to get stuck on the island 's shallow sub-continental shelves , it could majorly interfere with the animals ' ability to hunt for food .
`` The actual distance [ the animals ] have to travel to find food ( fish and krill ) really matters , '' Geraint Tarling , an ecologist with the British Antarctic Society , .
`` If they have to do a big detour , it @ @ @ @ @ @ @ back to their young in time to prevent them starving to death in the interim . ''
However , it appears that those underwater shelves are actually what has caused it to start breaking apart .
Before splitting in two , the iceberg began spinning clockwise , suggesting one end had been caught on the shelf .
The force of this snag is believed to be behind that split and the more recent fracturing as well .
Laura Gerrish , a GIS ( geographic information system ) mapping specialist at the British Antarctic @ @ @ @ @ @ @ new fragments , according to her post on Twitter : It is now hoped that the biggest pieces will be carried north of the island on a fast-moving current known as the Southern Antarctic Circumpolar Current Front .
However , if any of the pieces , or any potential new pieces , were to get caught on the shelves , they could still be big enough to cause disruption to the local wildlife , according to the BBC .
Researchers will now continue to monitor the situation over the holiday season , while @ @ @ @ @ @ @ a non-white Christmas .

The expedition ship M/S Explorer inches up to the edge of Iceberg A-68a with a humpback whale breaching the surface in the Weddell Sea.
The world's (former) largest iceberg continues to break apart into smaller pieces on the doorstep of a major marine wildlife haven and home to millions of macaroni and king penguins in Antarctica.
This comes less than a week after the mammoth iceberg, known as A68a, first split in two, Live Science recently reported .
Scientists at the U.S. National Ice Center (USNIC) spotted the two newest pieces, A68e and A68f, on Dec. 22 using images from the Sentinel-1A satellite, according to a USNIC statement . This means that there are now four separate iceberg fragments, including A68d, which will eventually drift away from one another.
A68a became the world's largest iceberg when it split from Antarctica 's Larsen C ice shelf in July 2017, Live Science previously reported . The massive chunk of ice has been drifting northward ever since. As recently as April, it measured 2,000 square miles (5,100 square kilometers), or just over the size of the state of Delaware.
Related: In photos: Antarctica's Larsen C ice shelf through time
In the spring of 2020, A-68a set its sights on South Georgia Island, a wildlife refuge in the South Atlantic Ocean that's home to millions of penguins, seals and other marine wildlife. Experts feared that if it were to get stuck on the island's shallow sub-continental shelves, it could majorly interfere with the animals' ability to hunt for food.
Image 1 of 5 Sentinel-1A satellite image of Iceberg A-68E and A-68F, in Dec. 22, 2020. (Image credit: European Space Agency) Mapping experts at British Antarctic Survey are tracking the route of the A-68a iceberg from satellite imagery. (Image credit: British Antarctic Survey) A map shows how A-68a has moved since cracking off of Larsen C. The blue lines show the historical tracks of other icebergs. (Image credit: contains modified Copernicus Sentinel data (2020), processed by ESA; Antarctic Iceberg Tracking Database) A Dec. 17 image shows A-68a after its big split, likely due to a collision with shallow seabed off the shore of South Georgia. (Image credit: ESA) A series of images taken over the course of more than two weeks show A-68a approaching South Georgia, then cracking and rotating after impacting an area of shallow seabed offshore. (Image credit: ESA)
"The actual distance [the animals] have to travel to find food (fish and krill) really matters," Geraint Tarling, an ecologist with the British Antarctic Society, said in a statement . "If they have to do a big detour, it means they're not going to get back to their young in time to prevent them starving to death in the interim."
However, it appears that those underwater shelves are actually what has caused it to start breaking apart. Before splitting in two, the iceberg began spinning clockwise, suggesting one end had been caught on the shelf. The force of this snag is believed to be behind that split and the more recent fracturing as well.
Laura Gerrish, a GIS (geographic information system) mapping specialist at the British Antarctic Survey, estimated the areas of the new fragments, according to her post on Twitter :
A-68a: 1,004 square miles (2,600 square km)
A-68d: 56 square miles (144 square km)
A-68e: 253 square miles (655 square km)
A-68f: 87 square miles (225 square km)
It is now hoped that the biggest pieces will be carried north of the island on a fast-moving current known as the Southern Antarctic Circumpolar Current Front. However, if any of the pieces, or any potential new pieces, were to get caught on the shelves, they could still be big enough to cause disruption to the local wildlife, according to the BBC.
Researchers will now continue to monitor the situation over the holiday season, while the island's inhabitants will hope for a non-white Christmas.
Originally published on Live Science.


livescience--2020-12-27--10 geological discoveries that absolutely rocked 2020

This year , scientists uncovered some of the Earth 's most well-kept secrets .
They found hidden rivers , chunks of lost continents and remnants of ancient rainforests , and they delved into the planet 's ancient history using cutting-edge technologies .
Who knows what they 'll unearth next !
While we wait to find out , here are 10 of the geological discoveries that rocked our world in 2020 .
The Yellowstone hotspot lurks beneath the national park 's geysers and hot springs , and about 9 million years ago , the volcano exploded in , scientists found .
@ @ @ @ @ @ @ volcanic deposits in the region , the team uncovered evidence of two previously unknown eruptions , which they named the McMullen Creek supereruption and the Grey 's Landing supereruption .
The Grey 's Landing eruption shattered records as the largest eruption of the Yellowstone hotspot ever detected ; about 8.72 million years ago , the eruption covered roughly 8,900 square miles ( 23,000 square kilometers ) of what is now southern Idaho and northern Nevada with volcanic debris .
Monstrous blobs near Earth 's core are bigger than we thought Continent-size blobs of @ @ @ @ @ @ @ 's solid mantle and liquid outer core , and now , scientists think they might be bigger than we ever imagined .
By previous estimates , the two largest blobs would measure 100 times taller than Mount Everest if pulled to the planet 's surface .
But after studying decades of seismic data from earthquakes , scientists now estimate that the big blob beneath the Pacific Ocean may actually be far more monstrous .
For instance , one newfound structure along the edge of the blob measured more than 620 miles ( 1,000 @ @ @ @ @ @ @ ago , a tsunami struck a plain between Great Britain and the Netherlands , submerging most of the region .
But research suggests that some islands may have , providing a home to Stone Age humans for thousands of years .
Though they remained above water for some time after the tsunami , rising sea levels eventually submerged the islands about 1,000 years later .
Scientists learned the lost islands had survived the tsunami only after collecting sediment from the seafloor near the eastern English estuary of the River Ouse .
The Earth @ @ @ @ @ @ @ ( 2,442 kms ) ball of iron — likely formed about , scientists estimate .
By recreating the conditions found in the core on a teeny , tiny scale , the team was able to calculate how long it would take for a blob of molten iron to build up to the core 's current size .
The time window of roughly 1 billion years lines up nicely with historic fluctuations in the planet 's magnetic field , which grew significantly stronger between 1 billion and 1.5 billion years ago .
The crystallization @ @ @ @ @ @ @ this boost of magnetism , since the process would have released heat into the liquid outer core ; heat drives a churning motion in the liquid that then powers the magnetic field .
About 150 million years ago , a now-lost continent broke up into enormous fragments — and one big chunk was recently discovered .
Scientists made the discovery while studying a type of diamond-bearing volcanic rock called kimberlite , which had been collected from nearly 250 miles ( 400 km ) beneath Baffin Island in northern Canada .
The mineral chemistry @ @ @ @ @ @ @ long-lost continent , making the sample location the deepest point where evidence of the continent had ever been found .
This year , scientists of cold , salty water that flow from the Australian coast out into the deep ocean .
The rivers , which researchers found using autonomous underwater vehicles , form when shallow waters near the coast lose heat during the winter .
Evaporation during the summer months makes this shallow water saltier than deep water , so when it cools , the dense , salty water sinks and snakes through @ @ @ @ @ @ @ These rivers span thousands of miles and carry nutrients , plant and animal matter and pollutants out into the ocean .
Related : Massive underwater rivers were discovered off the coast of Australia Antarctica might be the last place you 'd expect to find , but that 's exactly what scientists found under the western side of the continent .
The forest 's remains were discovered in a sediment core drilled from a seabed near Pine Island Glacier .
A layer of sediment within the core stood out from the rest , as @ @ @ @ @ @ @ it ; upon closer inspection , scientists found ancient pollen , spores , bits of flowering plants and a network of roots within the layer .
The sample dated back 90 million years , to the mid-Cretaceous period , when the now-frozen Antarctic had a much milder climate .
A seabed that once lined the bottom of the Pacific Ocean was found buried , where it continues to descend toward the Earth 's mantle transition zone .
The slab of rock once sat atop the oceanic lithosphere , the outermost layer of Earth @ @ @ @ @ @ @ when it collided with a neighboring tectonic plate , in what 's called a subduction event .
Scientists had never detected a subduction event so deep beneath the planet surface , at depths ranging between 254 to 410 miles ( 410 to 660 km ) underground .
Related : Ancient fragment of the Pacific Ocean found buried 400 miles below China Scientists digitally and showed that its movement likely gave rise to an arc of volcanoes in the Pacific Ocean some 60 million years ago .
In the past , some geophysicists argued @ @ @ @ @ @ @ , never existed .
But if it did exist , the plate would have been pushed beneath Earth 's crust tens of millions of years ago ; so using computer reconstruction , scientists reversed that motion , virtually pulling it and other ancient plates back to the surface .
They found that Resurrection would have fit in like a perfect puzzle piece , just east of two plates called Kula and Farallon , and that its edge matches up with ancient volcanic belts in Washington State and Alaska .
The discovered in more @ @ @ @ @ @ @ Empire State Building .
Measuring 1,640 feet ( 500 meters ) high from base to tip , the tower of coral stands freely near the rest of the Great Barrier Reef off the coast of Australia .
The blade-like structure measures 1 mile ( 1.5 km ) wide at its base and its peak sits about 130 feet ( 40 m ) below the sea 's surface .
Related : Coral 'tower ' taller than the Empire State Building discovered off Australian coast

This year, scientists uncovered some of the Earth's most well-kept secrets. They found hidden rivers, chunks of lost continents and remnants of ancient rainforests, and they delved into the planet's ancient history using cutting-edge technologies. Who knows what they'll unearth next! While we wait to find out, here are 10 of the geological discoveries that rocked our world in 2020.
Historic supereruption at Yellowstone
(Image credit: National Park Service)
The Yellowstone hotspot lurks beneath the national park's geysers and hot springs, and about 9 million years ago, the volcano exploded in two historic supereruptions , scientists found. After analyzing ancient volcanic rock tracts and volcanic deposits in the region, the team uncovered evidence of two previously unknown eruptions, which they named the McMullen Creek supereruption and the Grey's Landing supereruption. The Grey's Landing eruption shattered records as the largest eruption of the Yellowstone hotspot ever detected; about 8.72 million years ago, the eruption covered roughly 8,900 square miles (23,000 square kilometers) of what is now southern Idaho and northern Nevada with volcanic debris.
Monstrous blobs near Earth's core are bigger than we thought
(Image credit: Doyeon Kim/University of Maryland)
Continent-size blobs of rock sit at the boundary of Earth's solid mantle and liquid outer core, and now, scientists think they might be bigger than we ever imagined . By previous estimates, the two largest blobs would measure 100 times taller than Mount Everest if pulled to the planet's surface. But after studying decades of seismic data from earthquakes, scientists now estimate that the big blob beneath the Pacific Ocean may actually be far more monstrous. For instance, one newfound structure along the edge of the blob measured more than 620 miles (1,000 kilometers) across.
Lost islands in the North Sea withstood massive tsunami
(Image credit: Shutterstock)
Roughly 8,000 years ago, a tsunami struck a plain between Great Britain and the Netherlands, submerging most of the region. But research suggests that some islands may have withstood the tsunami , providing a home to Stone Age humans for thousands of years. Though they remained above water for some time after the tsunami, rising sea levels eventually submerged the islands about 1,000 years later. Scientists learned the lost islands had survived the tsunami only after collecting sediment from the seafloor near the eastern English estuary of the River Ouse.
Related: Changing Earth: 7 ideas to geoengineer our planet
Earth's core is a billion years old
(Image credit: Shutterstock)
The Earth's solid inner core — a 1,500-mile-wide (2,442 kms) ball of iron — likely formed about 1 billion to 1.3 billion years ago , scientists estimate. By recreating the conditions found in the core on a teeny, tiny scale, the team was able to calculate how long it would take for a blob of molten iron to build up to the core's current size. The time window of roughly 1 billion years lines up nicely with historic fluctuations in the planet's magnetic field, which grew significantly stronger between 1 billion and 1.5 billion years ago. The crystallization of the inner core may have provided this boost of magnetism, since the process would have released heat into the liquid outer core; heat drives a churning motion in the liquid that then powers the magnetic field.
Related: Earth's core is a billion years old
Piece of a lost continent found under Canada
(Image credit: Shutterstock)
About 150 million years ago, a now-lost continent broke up into enormous fragments — and one big chunk was recently discovered lurking under Canada . Scientists made the discovery while studying a type of diamond-bearing volcanic rock called kimberlite, which had been collected from nearly 250 miles (400 km) beneath Baffin Island in northern Canada. The mineral chemistry of the kimberlite matched that of the long-lost continent, making the sample location the deepest point where evidence of the continent had ever been found.
Related: Piece of lost continent discovered beneath Canada
Underwater rivers found near Australia
(Image credit: Shutterstock)
This year, scientists discovered massive rivers of cold, salty water that flow from the Australian coast out into the deep ocean. The rivers, which researchers found using autonomous underwater vehicles, form when shallow waters near the coast lose heat during the winter. Evaporation during the summer months makes this shallow water saltier than deep water, so when it cools, the dense, salty water sinks and snakes through the ocean as an underwater river. These rivers span thousands of miles and carry nutrients, plant and animal matter and pollutants out into the ocean.
Related: Massive underwater rivers were discovered off the coast of Australia
Ancient rainforest found under Antarctic ice
(Image credit: J. McKay/Alfred-Wegener-Institut; Creative Commons licence CC-BY 4.0)
Antarctica might be the last place you'd expect to find remnants of an ancient rainforest , but that's exactly what scientists found under the western side of the continent. The forest's remains were discovered in a sediment core drilled from a seabed near Pine Island Glacier. A layer of sediment within the core stood out from the rest, as its color clearly differed from those around it; upon closer inspection, scientists found ancient pollen, spores, bits of flowering plants and a network of roots within the layer. The sample dated back 90 million years, to the mid-Cretaceous period, when the now-frozen Antarctic had a much milder climate.
Related: Remains of 90 million-year-old rainforest discovered under Antarctic ice
Ancient seabed buried 400 miles beneath China
(Image credit: Matthias Kulka via Getty Images)
A seabed that once lined the bottom of the Pacific Ocean was found buried hundreds of miles beneath China , where it continues to descend toward the Earth's mantle transition zone. The slab of rock once sat atop the oceanic lithosphere, the outermost layer of Earth's surface, but was pushed downward when it collided with a neighboring tectonic plate, in what's called a subduction event. Scientists had never detected a subduction event so deep beneath the planet surface, at depths ranging between 254 to 410 miles (410 to 660 km) underground.
Related: Ancient fragment of the Pacific Ocean found buried 400 miles below China
Lost tectonic plate gets resurrected?
(Image credit: Stocktrek Images via Getty Images)
Scientists digitally reconstructed a tectonic plate and showed that its movement likely gave rise to an arc of volcanoes in the Pacific Ocean some 60 million years ago. In the past, some geophysicists argued that the plate, known as Resurrection, never existed. But if it did exist, the plate would have been pushed beneath Earth's crust tens of millions of years ago; so using computer reconstruction, scientists reversed that motion, virtually pulling it and other ancient plates back to the surface. They found that Resurrection would have fit in like a perfect puzzle piece, just east of two plates called Kula and Farallon, and that its edge matches up with ancient volcanic belts in Washington State and Alaska.
Related: 'Lost' tectonic plate called Resurrection hidden under the Pacific
Towering coral structure dwarfs Empire State Building
(Image credit: Schmidt Ocean Institute)
The first detached coral reef discovered in more than 100 years stands taller than the Empire State Building. Measuring 1,640 feet (500 meters) high from base to tip, the tower of coral stands freely near the rest of the Great Barrier Reef off the coast of Australia. The blade-like structure measures 1 mile (1.5 km) wide at its base and its peak sits about 130 feet (40 m) below the sea's surface.
Related: Coral 'tower' taller than the Empire State Building discovered off Australian coast
Originally published on Live Science.


livescience--2020-12-28--Bats are superheroes of the night. Their superpowers could help us protect them.

Many of us might struggle to see a moose on a moonless night , let alone a mosquito .
But some bats have a nifty trick — they use their ears to locate their bug prey .
It 's not that ca n't see — many have excellent full-color vision — but most do n't depend on their eyes to navigate .
For many bats , the challenge they must overcome to survive is detecting prey that move in the dark .
Enter echolocation .
Many bats can use returning echoes to detect objects as fine as a human hair @ @ @ @ @ @ @ the echoes in a way that lets them home in on insects or avoid obstacles .
Bats use of echolocation can help us protect them .
These cryptic creatures flit around at night and hide by day , making it difficult to monitor them by sight .
How many bats are there and what species are where ?
This is increasingly important information to know , because North American bats are being devastated by a deadly fungal disease called white nose syndrome ( WNS ) .
In eastern North America , WNS has @ @ @ @ @ @ @ % or more .
By studying bats in British Columbia and Alberta , where the fungus has not yet arrived , we hope to help bats survive when the fungus inevitably shows up there .
Understanding how bats echolocate , and then recording them appropriately , is fundamental to that effort .
Some bats are loud , some less so ; some species prefer to feed amongst trees , others over water .
Some bats , particularly ones that can snatch prey off of the ground or leaves , have huge ears to @ @ @ @ @ @ @ generated by their prey — like the flutter of moth wings .
Most others rely on smaller ears that are adept at listening for echoes but not necessarily to the sounds that their prey generate .
The one problem with this system is that sound waves need to bounce off an object to generate an echo .
That means the length of the sound wave has to match the size of the object so that the sound is blocked and bounces back to the bat .
Insects are small , so the sound @ @ @ @ @ @ @ short wavelengths result in high-frequency sounds .
Most bats produce such high-frequency sounds that ca n't hear them — hence , it is called ultrasound .
Ultrasound does n't actually travel very far in air , though , so most bats have to really belt their echolocation calls out in order to have enough sound range to avoid flying into an object before they detect it or to find a tiny insect in front of them .
It 's sort of like headlights on a car — bright lights are needed to drive @ @ @ @ @ @ @ and have their sound travel far .
This results in another problem .
The sounds bats make can be absolutely deafening to bats themselves — the equivalent of holding a shrieking smoke detector up to your ear if the sound were within human hearing range .
Bats generate these really loud sounds right next to their own ears so how do they not deafen themselves ?
Bats use their middle ear muscles to essentially `` close their ears '' while they are sending out sound waves .
Of course , to hear the @ @ @ @ @ @ @ re-open their ears .
Bats can do this 10 times per second .
Interestingly , some bat prey have also developed the ability to hear bats ' sounds and take evasive action , setting up a relentless battle of who hears who first .
Bats also tailor their sound to what they are finding .
They may use only a small range of relatively lower frequencies while se arching for insects , then switch to higher frequencies to discover size , distance and speed of movement to narrow in on a target .
@ @ @ @ @ @ @ sound frequencies can help us identify species flying around unseen in the night sky .
Using acoustic detectors , we can listen in on ultrasonic bat calls and then analyze the acoustic patterns to figure out what species of bats are in the neighborhood .
But the variation in the calls that one individual can make is tremendous , making the study of bat sounds challenging .
Listening for bats is an excellent way for us to fill in the many gaps in our understanding of which bats are present in different habitats @ @ @ @ @ @ @ time when bats are facing many challenges like the steady spread of WNS .
We 're keeping our ears open to better understand how we can help these fascinating creatures .
What we do n't want to be listening to is silence .
Cori Lausen is Associate Conservation Scientist with Wildlife Conservation Society ( WCS ) Canada , where she leads the Western Bat Program .
[ If you want to hear some bat sounds for yourself , listen to this audio interview with Dr. Lausen .
For more information on WCS Canada @ @ @ @ @ @ @ ]

Many of us might struggle to see a moose on a moonless night, let alone a mosquito. But some bats have a nifty trick — they use their ears to locate their bug prey. It's not that bats can't see — many have excellent full-color vision — but most don't depend on their eyes to navigate. For many bats, the challenge they must overcome to survive is detecting prey that move in the dark.
Enter echolocation. Many bats can use returning echoes to detect objects as fine as a human hair in total darkness. Bat brains map the echoes in a way that lets them home in on insects or avoid obstacles. Bats use of echolocation can help us protect them.
These cryptic creatures flit around at night and hide by day, making it difficult to monitor them by sight.
Related: Photos: The eerily beautiful bats of Arizona
How many bats are there and what species are where? This is increasingly important information to know, because North American bats are being devastated by a deadly fungal disease called white nose syndrome (WNS).
In eastern North America, WNS has reduced bat populations by an estimated 90% or more. By studying bats in British Columbia and Alberta, where the fungus has not yet arrived, we hope to help bats survive when the fungus inevitably shows up there. Understanding how bats echolocate, and then recording them appropriately, is fundamental to that effort.
Some bats are loud, some less so; some species prefer to feed amongst trees, others over water. Some bats, particularly ones that can snatch prey off of the ground or leaves, have huge ears to capture both echoes and the soft sounds generated by their prey — like the flutter of moth wings. Most others rely on smaller ears that are adept at listening for echoes but not necessarily to the sounds that their prey generate.
The one problem with this system is that sound waves need to bounce off an object to generate an echo. That means the length of the sound wave has to match the size of the object so that the sound is blocked and bounces back to the bat. Insects are small, so the sound's wavelengths must be small. These short wavelengths result in high-frequency sounds. Most bats produce such high-frequency sounds that human ears can't hear them — hence, it is called ultrasound.
Ultrasound doesn't actually travel very far in air, though, so most bats have to really belt their echolocation calls out in order to have enough sound range to avoid flying into an object before they detect it or to find a tiny insect in front of them. It's sort of like headlights on a car — bright lights are needed to drive fast. Faster bats must be loud and have their sound travel far.
This results in another problem. The sounds bats make can be absolutely deafening to bats themselves — the equivalent of holding a shrieking smoke detector up to your ear if the sound were within human hearing range. Bats generate these really loud sounds right next to their own ears so how do they not deafen themselves?
Bats use their middle ear muscles to essentially "close their ears" while they are sending out sound waves. Of course, to hear the reflected sound waves, they must quickly re-open their ears. Bats can do this 10 times per second. Interestingly, some bat prey have also developed the ability to hear bats' sounds and take evasive action, setting up a relentless battle of who hears who first.
Bats also tailor their sound to what they are finding. They may use only a small range of relatively lower frequencies while se arching for insects, then switch to higher frequencies to discover size, distance and speed of movement to narrow in on a target.
The way that different species use different sound frequencies can help us identify species flying around unseen in the night sky. Using acoustic detectors, we can listen in on ultrasonic bat calls and then analyze the acoustic patterns to figure out what species of bats are in the neighborhood. But the variation in the calls that one individual can make is tremendous, making the study of bat sounds challenging.
Listening for bats is an excellent way for us to fill in the many gaps in our understanding of which bats are present in different habitats. This monitoring is critical at a time when bats are facing many challenges like the steady spread of WNS. We're keeping our ears open to better understand how we can help these fascinating creatures. What we don't want to be listening to is silence.
Cori Lausen is Associate Conservation Scientist with Wildlife Conservation Society (WCS) Canada, where she leads the Western Bat Program.
[If you want to hear some bat sounds for yourself, listen to this audio interview with Dr. Lausen. For more information on WCS Canada bat conservation science, visit WCSbats.ca.]