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Buried lakes of liquid water discovered on Mars – BBC News

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Three underground lakes have been detected near the south pole of Mars.

Scientists also confirmed the existence of a fourth lake – the presence of which was hinted at in 2018.

Liquid water is vital for biology, so the finding will be of interest to researchers studying the potential for life elsewhere in the Solar System.

But the lakes are also thought to be extremely salty, which could make it difficult for any microbial life to survive in them.

Mars’ thin atmosphere means that the presence of liquid water on the surface is a near-impossibility. But water could remain liquid below ground.

The latest discovery was made using data from a radar instrument on the European Space Agency’s (Esa) Mars Express spacecraft, which has been orbiting the Red Planet since December 2003.

In 2018, researchers used data from the Marsis radar to report signs of a 20km-wide subsurface lake located 1.5km under Mars’ south polar layered deposits, a thick polar cap formed by layers of ice and dust.

However, that finding was based on 29 observations collected by Marsis between 2012 and 2015. Now, a team including many of the same scientists from the 2018 study have analysed a much bigger dataset of 134 radar profiles gathered between 2010 and 2019.

“Not only did we confirm the position, extent and strength of the reflector from our 2018 study, but we found three new bright areas,” said co-author Elena Pettinelli from Roma Tre University in Italy.

“The main lake is surrounded by smaller bodies of liquid water, but because of the technical characteristics of the radar, and of its distance from the Martian surface, we cannot conclusively determine whether they are interconnected.”

The team borrowed a technique commonly used in radar sounder investigations of sub-glacial lakes in Antarctica, Canada and Greenland, adapting the method to analyse the data from Marsis.

“The interpretation that best reconciles all the available evidence is that the high intensity reflections (from Mars) are coming from extended pools of liquid water,” said co-author Sebastian Lauro, also from Roma Tre University.

There’s not enough heat at these depths to melt the ice, so scientists believe the liquid water must contain high concentrations of dissolved salts. These chemical salts (different to the stuff we sprinkle on our chips) can significantly lower water’s freezing point.

In fact, recent experiments have shown that water with dissolved salts of magnesium and calcium perchlorate (a chemical compound containing chlorine bound to four oxygens) can remain liquid at temperatures of -123C.

“These experiments have demonstrated that brines can persist for geologically significant periods of time even at the temperatures typical of the Martian polar regions (considerably below the freezing temperature of pure water),” said co-author Graziella Caprarelli, from the University of Southern Queensland, Australia.

“Therefore we think that any process of formation and persistence of sub-ice water beneath the ice polar caps requires the liquid to have high salinity.”

Whether life could survive in such conditions depends on just how salty these Martian pools are. On Earth, only very specific types of microbes, known as halophiles, can survive in the saltiest bodies of water.

Roberto Orosei, chief scientist on the Marsis experiment, said: “While the existence of a single sub-glacial lake could be attributed to exceptional conditions such as the presence of a volcano under the ice sheet, the discovery of an entire system of lakes implies that their formation process is relatively simple and common, and that these lakes have probably existed for much of Mars’ history.

“For this reason, they could still retain traces of any life forms that could have evolved when Mars had a dense atmosphere, a milder climate and the presence of liquid water on the surface, similar to the early Earth.”

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NASA’s OSIRIS-REx grabs rocks from asteroid in historic mission – Al Jazeera English

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A NASA spacecraft touched down on the rugged surface of the Bennu asteroid on Tuesday, grabbing a sample of rocks dating back to the birth of the solar system to bring home.

It was a first for the United States – only Japan has previously secured asteroid samples.

The so-called “Touch-And-Go” manoeuvre was managed by Lockheed Martin Space in Denver, Colorado, where at 6.12pm (22:12 GMT) on Tuesday an announcer said: “Touchdown declared. Sampling is in progress,” and scientists erupted in celebration.

Seconds later, the Lockheed mission operator Estelle Church confirmed the spacecraft had eased away from the space rock after making contact, announcing: “Sample collection is complete and the back-away burn has executed.”

The historic mission was 12 years in the making and rested on a critical 16-second period where the minivan-sized OSIRIS-REx spacecraft extended its 11-foot (3.35-metre) robotic arm towards a flat patch of gravel near Bennu’s north pole and plucked the sample of rocks – NASA’s first handful of pristine asteroid rocks.

The probe will send back images of the sample collection on Wednesday and throughout the week so scientists can examine how much material was retrieved and determine whether the probe will need to make another collection attempt.

This mosaic image of asteroid Bennu was composed of 12 PolyCam images collected on December 2, 2018 by the OSIRIS-REx spacecraft from a range of 15 miles (24 km) [NASA/Goddard/University of Arizona/Handout via Reuters]

Scientists want at least 2 ounces (60 grams) and, ideally, closer to 4 pounds (2 kilogrammes) of Bennu’s black, crumbly, carbon-rich material – thought to contain the building blocks of the solar system. The asteroid is located more than 200 million miles (321.9 million kms) from Earth.

NASA’s science mission chief, Thomas Zurbuchen, likened Bennu to the Rosetta Stone: “Something that’s out there and tells the history of our entire Earth, of the solar system, during the last billions of years.”

‘Exactly perfect’

If a successful collection is confirmed, the spacecraft will begin its journey back towards Earth, arriving in 2023.

“Everything went just exactly perfect,” Dante Lauretta, OSIRIS-REx principal investigator from the University of Arizona, Tucson, said on a NASA live feed from Lockheed’s mission support building. “We have overcome the amazing challenges that this asteroid has thrown at us, and the spacecraft appears to have operated flawlessly.”

The robotic arm’s collection device, shaped like an oversized shower head, is designed to release pressurised gas to kick up debris.

The spacecraft launched in 2016 from Kennedy Space Center for the journey to Bennu. It has been in orbit around the asteroid for nearly two years preparing for the Touch and Go manoeuvre.

Bennu, which is more than 4.5 billion years old, was selected as a target because scientists believe it is a small fragment of what was once a much larger space rock that broke off during a collision between two asteroids early on in the history of the solar system.

“Asteroids are like time capsules floating in space that can provide a fossil record of the birth of our solar system,” Lori Glaze, NASA’s director of Planetary Science, told Al Jazeera. “They can provide valuable information about how planets, like our own, came to be.”

Thanks to data collected from orbit, the NASA team has determined two key discoveries: first, that between 5 and 10 percent of Bennu’s mass is water, and second, that its surface is littered with carbon-rich molecules. Atomic-level analysis of samples from Bennu could help scientists better understand what role asteroids played in bringing water to the Earth and seeding it with the prebiotic material that provided the building blocks for life.

Studying that material could also help scientists discover whether life exists elsewhere in the solar system, as well.

“If this kind of chemistry is happening in the early solar system, it probably happened in other solar systems as well,” Lauretta, OSIRIS-Rex’s principal investigator, told Al Jazeera in an interview ahead of Tuesday’s breakthrough. “It helps us assess the likelihood of the origin of life occurring throughout the galaxy and, ultimately, throughout the universe.”

Japan expects samples from its second asteroid mission – in the milligramMEs at most – to land in the Australian desert in December.

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New Research Provides Comprehensive Reconstruction of End-Permian Mass Extinction | Paleontology – Sci-News.com

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The end-Permian mass extinction, also known as the Permian-Triassic extinction event and the Great Dying, is the largest mass extinction event in Earth’s history that peaked about 252.3 million years ago. The catastrophe killed off nearly 96% of all marine species and 70% of terrestrial vertebrate species on the planet over the course of thousands of years. Massive eruptions in a volcanic system called the Siberian Traps are thought to have played an important role, but the causational trigger and its feedbacks are yet to be fully understood. Now, a research team led by Dr. Hana Jurikova from the GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel and the Helmholtz Zentrum Potsdam has assembled a consistent biogeochemical reconstruction of the mechanisms that resulted in the end-Permian extinction.

An illustration depicting the onset of the end-Permian mass extinction. Image credit: Dawid Adam Iurino / PaleoFactory, Sapienza University of Rome / Jurikova et al, doi: 10.1038/s41561-020-00646-4.

Dr. Jurikova and her colleagues studied isotopes of the element boron in the calcareous shells of fossil brachiopods and determined the rate of ocean acidification over the Permian-Triassic boundary.

“These are clam-like organisms that have existed on Earth for more than 500 million years,” Dr. Jurikova said.

“We were able to use well-preserved brachiopod fossils from the Southern Alps for our analyses.”

“These shells were deposited at the bottom of the shallow shelf seas of the Tethys Ocean 252 million years ago and recorded the environmental conditions shortly before and at the beginning of extinction.”

Because the ocean pH and atmospheric carbon dioxide are closely coupled, the researchers were able to reconstruct changes in atmospheric carbon dioxide at the onset of the extinction from boron and carbon isotopes.

They then used an innovative geochemical model to study the impact of the carbon dioxide injection on the environment.

“With this technique, we can not only reconstruct the evolution of the atmospheric carbon dioxide concentrations, but also clearly trace it back to volcanic activity,” said co-author Dr. Marcus Gutjahr, a researcher at the GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel.

“The dissolution of methane hydrates, which had been suggested as a potential further cause, is highly unlikely based on our data.”

“Without these new techniques it would be difficult to reconstruct environmental processes more than 250 million years ago in the same level of detail as we have done now,” said co-author Professor Anton Eisenhauer, also from the GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel.

The team’s findings showed that volcanic eruptions in Siberian Traps released immense amounts of carbon dioxide into the atmosphere.

This release lasted several millennia and led to a strong greenhouse effect on the late Permian world, causing extreme warming and acidification of the ocean.

Dramatic changes in chemical weathering on land altered productivity and nutrient cycling in the ocean, and ultimately led to vast de-oxygenation of the ocean.

The resulting multiple environmental stressors combined to wipe out a wide variety of animal and plant groups.

“We are dealing with a cascading catastrophe in which the rise of carbon dioxide in the atmosphere set off a chain of events that successively extinguished almost all life in the seas,” Dr. Jurikova said.

“Ancient volcanic eruptions of this kind are not directly comparable to anthropogenic carbon emissions, and in fact all modern fossil fuel reserves are far too insufficient to release as much carbon dioxide over hundreds of years, let alone thousands of years as was released 252 million years ago.”

“But it is astonishing that humanity’s carbon dioxide emission rate is currently 14 times higher than the annual emission rate at the time that marked the greatest biological catastrophe in Earth’s history.”

The study was published in the journal Nature Geoscience.

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H. Jurikova et al. Permian-Triassic mass extinction pulses driven by major marine carbon cycle perturbations. Nat. Geosci, published online October 19, 2020; doi: 10.1038/s41561-020-00646-4

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Haunted houses find ways around COVID 19

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Psychotic clowns. Axe murderers. Bedrooms possessed by poltergeists.

Many of the frights greeting visitors of horror attractions this Halloween will be familiar, but the thrill-creators behind them say one terrifying experience is squarely off-limits: the terrors of COVID-19.

Before the pandemic shook our lives, haunted houses sometimes dipped into the fears of contagion, splashing themed rooms with signs of a viral outbreak, hazmat suits and contamination warnings.

But with those experiences uncomfortably close to reality this year, horror masters like Shawn Lippert say reminding people of the virus is one line they’re not willing to cross.

“We use the analogy: Treat `COVID’ like the F-word in church,” said the owner of Scarehouse, an industrial-sized indoor haunted house in Windsor, Ont.

“It’s too real and so close to home. It’s almost like when you tell a joke and they say, `Too soon.”’

Lippert said that’s one of several rules he’s introduced at his haunt in order to keep people feeling safe and heath authorities satisfied. Ticketholders arrive at staggered times, and everyone is required to wear a mask.

Creepy objects that once brushed against visitors have been removed, and the giant airbags that evoke the feeling of claustrophobia have been stowed away to decrease the potential spread of germs.

Lippert describes those as small changes in a challenging year.

Many haunt operators were jittery about moving ahead with their usual Halloween festivities, considering health authorities could shut down the houses without much notice if the region experiences a surge in local cases. That would leave a brutal dent in their investments.

“If we can keep our doors open for the full run at this point, that would be a success for us,” Lippert said.

Several Toronto haunted houses decided the risk was too high. Casa Loma’s Legends of Horror and 28-year pillar Screemers at Exhibition Place were among the operators who decided to sit this year out, even before the city introduced tighter restrictions that would’ve closed them anyway.

Some organizers have used the pandemic to imagine ways to scare the living daylights out of people from a distance — often from the safety of their own vehicles.

The Pickering Museum Village put a historic spin on its spooky experience with a drive-thru tour that urged visitors to creep their cars along a roadway checkered with old houses, as ghost stories played on their FM radios.

Others have gone online with virtual group parties for kids or, for those of legal drinking age, what’s being sold as Canada’s first Virtual Halloween Cocktail Crawl.

Mentalist Jaymes White decided to embrace the digital world this year for his annual Halloween seances. His new Zoom experience, called Evoke, invites a small circle of friends to channel a spirit through video chat. He admits the idea goes against the traditions of a seance, where people usually hold hands around a table, but he’s confident the spirits will still be ready to unsettle his guests.

“They don’t care that we have a pandemic,” he said.

Paul Magnuson, one of the leaders at Calgary artist collective Big Art, will take over a downtown self-serve car wash for three days for a drive-in of the dead later this month.

Scare Wash is described as a trip to hell and back that begins when a wash attendee’s seemingly normal car rinse spirals into a nightmare.

Magnuson came up with the idea when it was clear plans for his usual neighbourhood spectacle wouldn’t be possible in the pandemic.

“Last year I turned my garage into a Dexter killer room where we did performances all night. In previous years I’ve had an interactive cemetery,” he said.

“I’m not going to let COVID take this holiday.”

Robby Lavoie felt a similar conviction for keeping Terror Train on track this year at the National Ontario Railroad Museum and Heritage Centre. The annual Halloween event draws thousands of people to Capreol, Ont., part of Greater Sudbury, and provides the museum with a healthy dose of revenue.

Lavoie said he drew inspiration from videos he saw of a Japanese zombie drive-in haunted house over the summer. He knew there was a way to tone down the gore and make the idea a bit more Canadian.

After speaking with museum organizers, Lavoie secured the board’s approval for “Inferno 6077,” an immersive drive-in horror experience inside the garage of the fire hall.

Pulling from his own knowledge of working in live theatre and movies, Lavoie began thinking on a grand scale. He hired a local writer who penned a story about townsfolk who seek revenge on an old man, and built rolling set pieces for the spectacle, which reaches its peak when the space is engulfed in flames, an illusion created with lights and projections.

“We’re putting you almost in an interactive movie, and it all came together within a month,” he said.

“I see myself doing this again next year, even if there isn’t COVID.”

Kathrine Petch understands the urge to keep Halloween on the calendar. As the general manager of Deadmonton Haunted House in Edmonton, she’s laid down strict COVID-19 precautions for their Area 51-themed haunt.

“The absolute, pure excitement of the customers is contagious to us,” she said.

“As long as we can pay the bills and have some money left over to make a different haunted house next year, I think we’ll be pretty happy.”

Petch said keeping Deadmonton open during the pandemic was important to everyone who runs the show.

“One of our biggest goals was to provide people with some kind of escape from all the crappiness that is 2020,” she said.

“And when they reach the end of our haunted house, at least they know the scares are done.”

Source: – CityNews Toronto

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