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Tough battle ahead for state of disaster

news

In a cartoon, using a visual metaphor can help describe another issue we may not have much understanding about. But just like with bushfires, if Australians band together, we can beat this

Heatwave Harry? Naming the threat may save lives

weather

Giving heatwaves names and strength ratings, as for cyclones, could help people in hot places such as Australia understand how dangerous they are, particularly as heatwaves worsen in future

Ancient Mars may have been covered in a huge ice sheet Credit: NASA

How the Martian ice age shaped the red planet

space

Mars was once covered in ice sheets that carved out thousands of giant valleys in the same way as on Earth, challenging previous theories of Mars as a warm, wet planet covered in oceans

Latest

Solved: the mystery of smelly armpits

science

Scientists now understand the substances that make armpits smell, that they predate Homo sapiens and they may have had an important role in communication between our ancestors

Aussie invents paint to beat coronavirus

science

In what may be one of the biggest breakthroughs yet in combating COVID-19, a scientist has invented a surface coating that wipes out the virus and may continue working for years

KFC plans to 3D print chicken nuggets

science

A fast-food chicken chain is creating lab-grown meat made from stem cells to create a “meat for the future”, as a burger chain feeds cattle lemongrass to try to cut methane emissions

Bushfires threaten 49 Australian species

animals

Scientists are just beginning to understand how the bushfires devastated populations of native animals. See the full list of species that are now – suddenly – under threat

Mars mission headlines big week in space news

space

UAE launched its first mission to Mars on Monday as it strives to reduce the country’s reliance on selling oil. On the ISS, NASA astronauts complete a space walk and prepare to head home

Uncomfortable uniforms could force girls out of sport

Teens in Sports Uniforms
sport

Girls are dropping out of sport at high rates as they move from tweens to teens and a new study is looking to see if uniforms are part of the problem

Calls to change cheese health star rating

Dairy case study
health

Despite more than 90 per cent of Australians not eating enough dairy, cheese is being overlooked as a source of calcium and “good” fats, with some cheeses only rating 1.5 health stars

Roadblock stops Premier’s getaway

news

Cartoonist Mark Knight discusses Victoria’s change of circumstances as coronavirus case numbers increase, and whether Premier Daniel Andrews is running away from responsibility

Race is on to reach the Red Planet

space

Traffic is about to get busy on the interplanetary route between Earth and Mars as three rival missions leave Earth during July in time for the next Earth-Mars Close Approach in October

Virus spread leads to remote learning return

COVID-19 Testing Increases As More Coronavirus Cases Confirmed In Victoria
news

Melbourne students have an extra week of holidays as schools face a return to remote learning while the city battles a second wave of coronavirus infections.

Why do we get wrinkly skin as we age?

explainers

Wrinkles are a normal part of ageing, except for the wrinkly fingers and toes people of any age can get when they’ve been in the bath or pool for too long. Kids News researched wrinkles

Calls to better protect world-famous giant cuttlefish site

animals

Pressure is mounting on the SA government to reverse a decision allowing fishing of giant cuttlefish in the Spencer Gulf, where they mass each year to spawn, the only place in the world this happens

Big buzz about Aussie bee drone invention

Pollination drone
technology

A team of mechanical engineering students in South Australia has invented a small drone that transfers pollen from plant to plant and that could one day replace bees

How you can help stop a bully

Bullying in the Corridor
safe kids

You might not have been bullied but chances are you’ve seen it happen to one of your classmates. Experts say bystanders make a choice to be part of the problem or part of the solution

New names for Redskin and Chicos lollies

civics

Nestle will rename its Red Skins and Chicos lollies as the names are now “out of step” with the company’s values and it wants to “keep creating smiles” rather than cause offence

Scientists map ancient lost continent

geography

Towering titanosaurs and other dinosaurs once roamed the vast, mountainless lands between the east of Australia and New Zealand on a lost continent called Zealandia

Concerns over spike in Victorian COVID-19 cases

health

Victoria’s new coronavirus cases — including AFL player Conor McKenna — are causing concern about how this could impact Australia’s economic recovery, reopening borders and sport

Giant meat-eating dinosaur roamed Australia

animals

Move over T-rex, Gigantosaurus and Spinosaurus — the discovery of dinosaur footprint fossils in Queensland reveal Australia had its own huge predator in the Jurassic Period.

Vitamin D could help fight food allergies in kids

Allergies case study
health

Australia has the world’s highest rate of childhood food allergies but researchers hope a simple vitamin supplement could help change that.

Teens making music about COVID-19

A singer shares COVID-19 messages
humanities

June 20 is World Refugee Day. Kids News shares a film by a teenager at Bidi Bidi refugee camp in Uganda about young people making music to help stop the spread of COVID-19

Call to ban junk food on kids’ social media

Junk Food adverts for Teens
health

Fast-food companies are bombarding children and teenagers on social media with ads for unhealthy junk food and drinks, according to a new study. Researchers want the ads banned

Trial to ‘switch off’ severe allergies in kids

Egg Allergy treatment
health

Kids could live free of life-threatening egg allergies thanks to a treatment being trialled by Australian researchers in Melbourne after the success of a similar trial for peanuts allergies

Discovery of Earth-like habitable planet

An artist rendition released by the European Space Agency on Wednesday, Nov. 28, 2007 shows the main bodies of the solar system, the Sun, Mercury, Venus, the Earth, from left in foreground, Uranus, Neptune, Saturn, Jupiter and Mars, from left in background. The Moon, the Earth's natural satellite, is seen at right in foreground, as the relative size of the orbits of the planets is not respected. Nearby planet Venus is looking a bit more Earth-like with frequent bursts of lightning confirmed by a new European space probe. For nearly three decades, astronomers have said Venus probably had lightning, ever since a 1978 NASA probe showed signs of electrical activity in its atmosphere. But experts were not sure because of signal interference. (AP
space

An exoplanet that orbits a star just like our Sun could be the most similar to Earth ever found, which has scientists thinking it could liveable.

Lost city found with radar and a quad bike

Face of the Emperor Constantine and latin script
history

A long-buried ancient Roman city in Italy has been mapped in incredible detail without any digging. Instead, archaeologists used a ground-penetrating radar strapped to a quad bike

The mystery of sea creatures’ snot palaces

science

Learning how sea creatures build the equivalent of five-story palaces in about an hour, made just with mucus from their heads, could help us build expanding homes on Earth, the Moon or Mars

Burnt koalas heal with Phillip Island penguins

environment

Phillip Island reopens on World Environment Day as Ranger Jess McKelson shares tales of bushfire koalas and little penguins

Goalkicking yips could be in players’ heads

sport

Have you ever wondered why footballers struggle to convert set shots for goal? Australian sports scientists believe the answer could be all in the mind

Australia set for colder, wetter than average winter

Weather
weather

Get your umbrella and winter woollies out. The Bureau of Meteorology is tipping plenty of rain and chilly days ahead but nights could be warmer.

Australian man’s new toilet paper world record

sport

A young Queensland soccer star has claimed his fourth Guinness World Record, despite most sport being cancelled during coronavirus-related restrictions

Big boost to birdwing butterflies in the wild

animals

A successful captive breeding and release program of more than 500 Richmond birdwing butterflies means the species could soon be taken off the threatened species list

No joke! Experts agree laughter is good for us

OP18_Summer Photo Call_Grades K-2
arts

Humour is as ancient as human life itself, but the joys of laughter never grow old and amusement experts believe we’re on the cusp of a COVID-19 comedy revolution

Caring for the billions of microbes in your mouth

Museum sugar drink ban
health

Donations of spit from about 1500 people are helping scientists understand how the billions of microbes in our mouths work to keep us healthy and what you can do to keep them healthy too

Unleash the little scribes to make mischief!

arts

Beloved Australian children’s author Andrew Daddo says storytelling platform Littlescribe invites kids to imagine breaking all the rules

Climbers to remeasure height of Everest

geography

A team of climbers is on its way to summit Mount Everest this week to measure whether it has grown as Earth’s tectonic plates move and try to end international disagreement on the subject

Gnarly home has its own skate bowl

QLD_CM_REALESTATE_MAINPIC_SKATEBOWLHOME_12MAY20
just for fun

Imagine the fun you’d have living in this cool house. Pool parties with friends are just the start. How about your own indoor skate bowl?

Isolation baby boom for Australian zoos

animals

While the world has been in lockdown, zoos around the country have been welcoming a wave of cute, cuddly and not so cuddly babies. Check them out.

Aussie AI song takes global music prize

A scene from the AI song video Beautiful the World
technology

A three-minute song written by artificial intelligence that turned koala grunts, kookaburra laughs and Tassie devil barks into a kind of instrument has won an international music competition

Coughing over the health of Australia’s piggy bank

Mark Knight's cartoon on Josh Frydenberg
civics

When Mark Knight tuned in to watch Treasurer Josh Frydenberg talk about the economy in federal parliament, he saw him coughing uncontrollably. What was the cause?

Spooky goings-on at night in the museum

A worker displays the 'Unlucky Mummy', from 945 BC, displayed by the British Museum during a press conference at Taiwan's National Palace Museum in Taipei 24 January 2007. According to the British museum, the 'Unlucky Mummy' is not a mummy at all, but rather a gessoed and painted wooden 'mummy-board' or inner coffin lid, found at Thebes. It is referred to as the 'Unlucky Mummy' as it has acquired a reputation for bringing misfortune. Some 271 pieces of antiques from the British Museum will be exhibited at Taiwan's National Palace Museum betwen 04 Febuary to 27 May 2007. AFP PHOTO/Sam YEH
history

British Museum guards have reported spooky goings-on including ghostly footsteps, strange lights and mysterious crying among the exhibits, like a real-life version of Night at the Museum

Mystery of koala drinking habits solved

animals

In a big win in the battle to save this species from extinction, scientists have observed koalas drinking in the wild for the first time, watching them lick rain running down tree trunks

Cave find rewrites history of early humans

Primeval Caveman Wearing Animal Skin Holds Stone Tipped Spear Looks Around, Explores Prehistoric Forest in a Hunt for Animal Prey. Neanderthal Going Hunting in the Jungle
history

Scientists have found human bones and a tooth up to 46,000 years old that rewrite the history of early humans’ arrival in Europe and time spent living alongside Neanderthals

River ‘monster’ to topple T-rex as top dinosaur

This is an artist's illustration of the terrifying creatureCredit: University of Portsmouth / Davide Bonadonna
animals

Fast, ferocious Spinosaurus is the first aquatic dinosaur known to science. Experts believe it could topple T-rex to take the title as the most famous and exciting meat-eating dinosaur

Aussie helps build ‘time machine’ to study Big Bang

Big Bang Theory. Source: Thinkstock.
science

An Australian-made radio telescope is preparing to look back 13 billion years in time to the Big Bang and discover the secrets of our universe. It will be the closest thing we have to a time machine

‘Crazy beast’ prehistoric mammal found

Supplied Editorial The Adalatherium was a bizarre creature that lived around 66 million
 years ago on the island of Madagascar. Picture: Facebook/Denver Museum of
 Nature & Science
animals

The skeleton of a backward-toothed mammal nicknamed “crazy beast” that existed alongside dinosaurs 66 million years ago has been unveiled by Australian palaeontologists

Exploring the 250th anniversary of Cook’s arrival

this
 ESCAPE HAWAII PHILIP HEADS STORY
 Sailing ship HM Bark Endeavour replica of the HMS Endeavour which carried Captain James Cook on his South Pacific expedition at anchor in Kealakekua Bay, Hawaii, USA 30 Oct 1999. 
 /Sailing/ships Picture: Ap
history

Wednesday, April 29, 2020 marks the 250th anniversary of James Cook’s arrival at Botany Bay. We explore why Cook came to Australia and why some celebrate and some lament this day

Earth’s insect numbers shrink over 30 years

Funny laughing curly girl with a butterfly on his nose.
animals

New scientific research has shown the number of insects living on land has fallen dramatically in the past 30 years, putting the world’s ecosystems — and human lives — at risk

Drones delivering COVID-19 test kits

technology

Aussies could soon be self-testing for COVID-19 with the help of a fleet of drones. A Melbourne-based drone company is already using tiny aircraft in Africa to deliver and return test kits

Virus leaves future of Virgin up in the air

Mark Knight cartoon on the future of Virgin Airlines
arts

In his weekly series, award-winning cartoonist Mark Knight explores the collapse of Virgin Airlines in Australia and how the company could make a buck selling its second-hand planes

Big find about origins of human language

A three-dimensional model of the 3.2 million-year-old hominid known as Lucy is unveiled at the Houston Museum of Natural Science Tuesday, Aug. 14, 2007. The sculpture, showing a scientific estimation of what Lucy may have looked like in life, is part of an exhibition featuring the original fossilized remains of the oldest and most complete adult human ancestor from Africa. Houston is the first stop on an American tour for the famous fossil. The exhibition will open Aug. 31. (AP Photo/Pat Sullivan)
science

By comparing brains of humans and apes, scientists have discovered the origins of human language could be 25 million years old — 20 million years older than previously thought

Earthquakes signal Iceland’s volcanoes waking up

science

Scientists warn that a volcanic area of Iceland is becoming active, with more than 8000 earthquakes recorded since January 21 and 10cm of land uplift as magma pushes up from below

Astronauts recall flawed Apollo 13 mission

space

It is 50 years since the near-disastrous Apollo 13 mission and though younger generations may think of it as a failure, its astronauts and others regard it as NASA’s finest achievement

Massive stringy clone colony filmed off WA

the siphonophore
animals

Researchers off WA have filmed a long, glowing, stringlike, predatory underwater creature made up of millions of interconnected clones, the largest of its type ever discovered

Scientists to make the Murray River sing

The Helping the Murray Sing project. Picture: Jason Macqueen
science

The sounds of Australia’s Murray River will soon be heard in song after scientists and audio specialists captured its sights and sounds in a project aimed at improving the waterway’s health

Oldest fossil of early human species is discovered

history

Australian and international scientists have unearthed a two-million-year old skull bone — the oldest known fossil of the earliest human species named Homo erectus

Why do grey seals clap like humans?

Wild grey seal. Picture: Ben Burville
animals

Amazing video captured by a marine biologist after 17 years of waiting shows breeding grey seals clapping at each other underwater to warn off competitors and attract mates

Exploring the lost city of Pompeii

history

On April 1, 1748, a Spanish engineer rediscovered Pompeii, changing the way we thought about historical artefacts and beginning the longest archaeological dig in the world

What and where is the equator?

explainers

Parachutists have set a world record for crossing the equator 12 times in a single jump, which got us wondering what the equator is, where it is and why do they launch space rockets there?

Baby boom for endangered snapping turtles

Turtle
animals

The future of Australia’s critically endangered Bellinger River snapping turtle is a little more secure after 35 baby turtles hatched at Taronga Zoo

Fish with fingers shows how human hand evolved

Supplied Editorial Fwd: FW: Reuters/image permission
animals

A slippery predator that lurked in lagoons 380 millions years ago had fins with finger bones that could teach us about the origins of the human hand

Mystery ‘Bonehenge’ woolly mammoth ring

Artist's impression of woolly mammoth
history

Archaeologists are uncovering a mysterious collection of mammoth bones arranged by our ancient Palaeolithic ancestors 20,000 years ago during the last Ice Age

Ban on indoor gatherings to limit spread of Covid-19

NBL Grand Final: Game 2 - Perth v Sydney
health

For the first time in history, Australians are being told not to travel overseas and indoor gatherings of more than 100 people are banned in an effort to keep people safe from COVID-19

Miracle change after double hand transplant

Shreya Siddanagowder gestures during an interview with AFP at her home in Pune, more than two years after she had both hands transplanted
health

A woman who received two hands from a male donor has found her new hands have transformed to be slimmer and like her own skin tone, in an incredible development that has pleased doctors

Farewell Aurora Australis, our beloved Antarctic ship

science

The Australian Antarctic Division’s famous bright orange research ship Aurora Australis departed for Macquarie Island this week on one last voyage before its retirement

WHO officially declares COVID-19 coronavirus a pandemic

health

As WHO officially declares the global coronavirus crisis a pandemic, PM Scott Morrison announces a $2.4 billion package for Australia’s health system to help it respond to the crisis

Footy legend learns of his grandfather’s great escape

The Australians trapped behind enemy lines
history

AFL legend Tom Harley grew up hearing bits of the story of his grandfather’s WWII escape. Now, for the first time, he’s learning the full details of an extraordinary adventure that is barely known

NASA on mission to strike gold in space in 2022

YLG Bullion International Co. Chief Executive Officer Pawan Nawawattanasub Interview And General Images Of Bullion
space

Space agency NASA has asked billionaire Elon Musk’s SpaceX to help explore a nearby asteroid called 16 Psyche that contains enough gold to make everyone on Earth a billionaire

Tasmania considers culling wild kookaburras

animals

Tasmania is considering culling kookaburras in the wild after populations of the iconic national bird have spread and are threatening the future of other native species

Spelling out the right time for formal language

Prime Minister's Spelling Bee logo for Kids News
spelling bee

Literacy experts want to end the myth that informal language used by young people in conversation is just poor formal language. It is, in fact, a modern form of conversation that has evolved for decades

Australia’s long, hot summers the new normal

weather

Our summers are now twice as long as our winters as climate change has increased temperatures since the middle of last century, according to a new study of Australian weather data

New type of ancient lion found in Australia

An artist impression of marsupial lion now known as Lekaneleo roskellya. Picture: Peter Schouten
animals

A new type of ancient marsupial lion has been discovered in Queensland after palaeontologists discovered its teeth were like nothing ever seen before

Aussie OJ and growers under threat

Various Australian orange juice brands - (l-r) bottles of Golden Circle, Crusta, Berri, Nippy's and Daily Juice.
news

Australians may not be able to drink fresh orange juice in as little as five years if major retailers don’t pay growers more to make up for drought and rising water costs

Tomb radar may solve Egyptian Queen mystery

history

A hidden chamber near the tomb of Egypt’s King Tutankhamun in the Valley of the Kings may contain the long-lost remains Queen Nefertiti

Scorching hot planet heading for destruction

Picture released 04/10/2006 by the European Space Agency shows an artist's impression of a Jupiter-sized planet passing in front of its parent star. Such events are called transits. When the planet transits the star, the star?s apparent brightness drops by a few percent for a short period.
space

Astronomers have discovered a planet where temperatures frequently hit 1000C, that has an 18-hour year and that will likely soon be destroyed when it spirals into its star or tidal forces tear it apart

Space tourists to go into super-high orbit in 2021

space

Up to four tourists could launch into a super-high space orbit in an autonomous SpaceX capsule by the end of next year, with ticket prices expected to be in the millions of dollars

Mystery coffin found in ancient Roman temple

Men dressed as ancient Roman centurions parade along the Fori Imperiali avenue, in front of ancient Colosseum on the occasion of the celebrations of the birth of the city of Rome, Sunday, April 22, 2012. Legend has it that Rome was founded on April 21, 753 B.C. by Romulus and his brother Remus, the twin sons of the god of war Mars, who were suckled as infants by a she-wolf in the woods. Known as the Christmas of Rome, each year Romans celebrate the pagan festivity, which has become a major tourist attraction, by dressing up in ancient Roman clothes and parading through the streets surrounding the eternal city's ancient ruins. (AP Photo/Alessandra Tarantino)
history

Archaeologists believe they have found the long lost tomb of Romulus, who legend says was raised with his twin brother by a wolf before founding the ancient city of Rome

Iconic Holden cars driven out of Australia

A Holden sign sits above the caryard of a Holden dealership in Sydney on December 11, 2013.  Struggling automaker GM Holden said it will shut down its manufacturing operations in Australia by 2017, shedding 2,900 jobs, in a major blow to the nation's car industry.  AFP PHOTO/William WEST
 
Pic. Afp 
Pic. Afp
news

The Holden car brand, an important part of Australia’s history for more than 160 years, will cease to exist in 2021. The move by US company General Motors has angered PM Scott Morrison and shocked motoring fans

Doctors keep heart alive in jar for 24 hours

Stethoscope and heart
health

Doctors have kept a heart beating for 24 hours in a jar with the new life-changing ULiSSES device, bringing hope to thousands of patients needing the lifesaving treatment

Is vandalising vandalism a new form of art?

Mark Knight's cartoon on Hosier Lane.
arts

In his weekly series, award-winning cartoonist Mark Knight considers if vandalising vandalism is a new art form after a gang of youths spray-painted street art in Melbourne’s famous Hosier Lane

Panama disease found on Queensland banana farm

news

A fungus that can wipe out banana crops has been found on a farm in far north Queensland in a region that produces 90 per cent of Australia’s bananas

Mammoth funnel-web stuns zoo

Massive funnel-web spider at Australian Reptile Park.
animals

Look away if you hate spiders, because this story is about a huge funnel-web called Dwayne “The Rock” Johnson. He’s so big he can produce enough venom to save many human lives

Keeping drinking water safe after fires

environment

Water experts are preparing to keep Australia’s drinking water clean after bushfires, including installing huge fabric curtains across Sydney’s main dam

Scientists urge action to save platypus

Baby zoo animals spread. Healesville Sanctuary. Platypus keeper Jessica Thomas with little Ember, named after the local bushfires.
animals

Platypus populations are on the brink of extinction from drought, land clearing and the way we manage our waterways, according to new research on this unique Australian icon

Five and 10 cent coins to ‘die naturally’

News 16.5.11 BCM The five cent coin will be phased out. Pic: Sarah Marshall
money

The head of the Royal Australian Mint has signalled the eventual end of the 5c and 10c coins. We look at the value of cash and when it could be the right time to let these coins go

Bionic jellyfish to explore our oceans

A jellyfish augmented with a microelectronics implant designed by researchers Nicole Xu and John Dabiri is seen in an artist's rendering released January 30, 2020. Rebecca Konte/Caltech/Handout via REUTERS.
science

Researchers have created super-fast bionic jellyfish to help explore the world’s oceans and monitor conditions such as temperature, salt levels, acidity and oxygen levels

WHO names coronavirus COVID-19

Airport
health

The World Health Organisation now officially has a name for the coronavirus that has infected more than 40,000 people around the world 

First-ever close-up of the Sun

This is the highest-resolution image of the Sun ever taken. Credit: NSO/NSF/AURA
space

Scientists have released the first photographs of the Sun from the new solar telescope in Hawaii, showing churning plasma that looks like a sea of gold nuggets, each as big as France

Lunch box sweet treats too salty

health

Kids and parents planning back-to-school lunches are warned to avoid unhealthy salty treats that contain almost the entire day’s salt allowance recommended for a child

What we searched for on Google 2010-2020

history

This year’s bushfires prompted a bigger spike in Australian Google search queries than any other news event this decade, with floods and Cyclone Yasi also making the top-topics list

Aussie schoolkids inventing the future

Lawsona and Gabrielle with their Aquerator invention
technology

A robotic aerator to save river fish, a voice app to help people living with dementia and a photo-recognition app that sorts rubbish have been named Australia’s top student inventions

Tourists rescued as island volcano erupts

geography

New Zealand’s White Island volcano has erupted suddenly forcing the dramatic rescue of tourists who were exploring the crater floor when it began to rumble

Sesame Street farewells its kindest, grouchiest star

Big Bird reads to Connor Scott and Tiffany Jiao during a taping of Sesame Street on Thursday, April 10, 2008 in New York. Being Big Bird is sweaty, physical work. But puppeteer Caroll Spinney, who has worked on Sesame Street for nearly four decades playing both Big Bird and Oscar the Grouch, has no wish to be anywhere else. (AP Photo/Mark Lennihan)
arts

Big Bird and Oscar the Grouch’s puppeteer — the “most unknown famous person” – has died after 50 years creating joy on Sesame Street

NASA’s totally unexpected Sun surprise

space

NASA’s Parker spacecraft has reported back that the Sun is sending out sudden, violent bursts of solar wind so powerful that the magnetic field flips itself in the opposite direction

Growing ‘mini brains’ and zapping them to life

Light bulb with brain inside the hands of the businessman.
science

In a world first, Australian scientists are zapping balls of brain cells they are growing in a laboratory to make them come to life in a real-life, good-news version of Frankenstein

First Aussie reaches heart of Antarctica

QLD_CM_NEWS_PINKPOLAR_3OCT19
humanities

An adventurer from Queensland has become the first Australian to reach Antarctica’s Pole of Inaccessibility, just one leg of an epic journey to help men and women experiencing breast cancer

Junk food tells lies to your brain

Chubby boy is looking at junk food plate
health

Sugary and fatty foods have the power to change how your brain works and stop you knowing when you’re full, but scientists believe you can retrain your brain to beat junk food addiction

Operating on Obama’s 3D-printed brain

Brain surgery
science

In a world-first, Australian doctors have operated on a 3D-printed brain to rehearse for a real brain operation. Up next, 40 brain surgeons operating on 3D printed brains all at once

Astronauts’ blood flows backwards in space

space

NASA doctors have made the surprising discovery that astronauts’ blood sometimes flows in reverse, with major implications for space tourism and trips to Mars