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article image Antarctica was home to a rainforest 90 million years ago – Digital Journal

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A team of researchers led by geoscientists from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research in Germany and scientists from Imperial College London, UK. have discovered fossil soil dating to the mid-Cretaceous Period, about 90 million years ago, suggesting that the climate was exceptionally warm at the time.

Their analysis of the preserved roots, pollen, and spores show that dense concentrations of atmospheric CO2 would have created much hotter global temperatures, melting polar ice sheets, and sending sea levels soaring to up to 170 meters (558 feet) higher than they are today. Their work was published in the journal Nature on April 1, 2020.

Co-author Professor Tina van de Flierdt, from the Department of Earth Science & Engineering at Imperial, said, per Science Daily: “The preservation of this 90-million-year-old forest is exceptional, but even more surprising is the world it reveals. Even during months of darkness, swampy temperate rainforests were able to grow close to the South Pole, revealing an even warmer climate than we expected.”

FS Polarstern in front of a mighty iceberg in Inner Pine Island Bay, West Antarctica.

JP Klages, Alfred Wegener Institute

Attention-grabbing sediment layer

During an expedition in 2017, aboard the RV Polarstern in the Amundsen Sea, researchers drilled deep underneath the seabed of West Antarctica, close to the location of the Pine Island and Thwaites glaciers, and only about 900 kilometers (560 miles) away from the South Pole.

What they pulled up from a depth of about 30 meters “quickly caught our attention. It clearly differed from the layers above it,” lead author Dr. Johann Klages, a geologist at the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research in Germany, said in a press release.

“The first analyses indicated that, at a depth of 27 to 30 meters (88 to 98 ft) below the ocean floor, we had found a layer originally formed on land, not in the ocean.”

First author Dr. Johann P. Klages (AWI) and co-author Prof. Dr. Tina van de Flierdt (Imperial Colleg...

First author Dr. Johann P. Klages (AWI) and co-author Prof. Dr. Tina van de Flierdt (Imperial College London) try to remove heavily solidified sediment from the MeBo core catchers.

Thomas Ronge; Alfred Wegener Institute

No one has ever pulled a Cretaceous Period sample out of the ground from such a southern point on the planet before – but the research team was not prepared for what they would find out after a further examination of the sediment was done with X-ray computed tomography (CT) scans.

Back on land, the CT Scans revealed soil that was so well-preserved that it still contained traces of pollen, spores, and remnants of flowering plants. Even intact individual cell structures could be observed. This all pointed to the preserved remains of an ancient rainforest that existed in Antarctica approximately 90 million years ago.

“The numerous plant remains indicate that the coast of West Antarctica was, back then, a dense temperate, swampy forest, with many conifers and tree ferns similar to the forests found in New Zealand today,” says palaeoecologist Ulrich Salzmann from Northumbria University in the UK.

Station meeting of geologists and geophysicists in the sounder center of the FS Polarstern.

Station meeting of geologists and geophysicists in the sounder center of the FS Polarstern.

JP Klages, Alfred Wegener Institute

An interesting reason for the unprecedented find

So how could it have been possible for a rainforest to grow and thrive at the South Pole? We do know that the mid-Cretaceous was the heyday of the dinosaurs – but was also the Earth’s warmest period in the past 140 million years, with ocean temperatures thought to be as high as 95 degrees Fahrenheit.

Then, as now, the South Pole would have been subjected to four months of unyielding darkness during the Antarctic winter. How could this ancient rainforest thrive, deprived of the Sun for so long? Based on biological and geochemical data contained in the soil sample, researchers used modeling to reconstruct what the ancient climate of this long-gone forest region might have been like.

They found out that atmospheric CO2 levels would have needed to be significantly higher than scientists realized. It was a super-heated environment, with an average air temperature of around 12 degrees Celsius or 54 degrees Fahrenheit in the Antarctic.

“Before our study, the general assumption was that the global carbon dioxide concentration in the Cretaceous was roughly 1,000 parts per million (ppm),” explains geoscientist Torsten Bickert from the University of Bremen in Germany. “But in our model-based experiments, it took concentration levels of 1,120 to 1,680 ppm to reach the average temperatures back then in the Antarctic.”

There is still one big question to be answered: If Antarctica used to be so warm, what caused it to dramatically cool, asks CBS News, allowing the formation of ice sheets? According to co-author and AWI climate modeler Dr. Gerrit Lohmann, in all of their climate simulations, researchers were “unable to find a satisfactory answer.”

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COVID-19: Fanshawe team studies possible way to stop virus's spread in body – London Free Press (Blogs)

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Fanshawe College researchers in London are studying a process that could lead to an effective treatment for COVID-19.

“When a virus enters the body, its ability to produce devastating effects is due to its capacity to make copies of itself while evading the body’s immune system,” said Abdulla Mahboob, manager of Fanshawe’s Centre for Applied Research and Innovation in Biotechnology (CARIB) labs, where the study is underway.

The college team is testing a custom inhibitor they hope will block virus proteins from binding together to help the virus’s genetic material get past cell defences, he said. “If we stop the proteins from binding together, we can expose the virus to the cell’s immunity, which in turn will stop the spread of the virus itself in the patient.”

Scientists are testing the inhibitor using mammalian cells containing the specific proteins targeted in the study, with promising results, the college said.

If effective, the inhibitors would then be tested on the virus in lab-grown cells and work would begin to turn it into a viable treatment for the respiratory disease.

It’s the latest in a number of studies by college scientists, including one looking at the potential benefits of cannabis extract in treating blood clots and inflammation in life-threatening COVID-19 cases.

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Take 2 for SpaceX's first astronaut launch with more storms – CTV News

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CAPE CANAVERAL, FLA. —
SpaceX pressed ahead with its second attempt to launch astronauts for NASA — a historic first for a private company — but more stormy weather threatened more delays.

Elon Musk’s company came within 17 minutes Wednesday of launching a pair of NASA astronauts for the first time in nearly a decade from the U.S., before the threat of lightning forced a delay.

NASA Administrator Jim Bridenstine said managers were debating whether to bump the next launch attempt from Saturday to Sunday to take advantage of a slightly improved forecast at Kennedy Space Center.

At an outdoor news conference Friday, Bridenstine stressed the need for safety for astronauts Doug Hurley and Bob Behnken — no matter how many times it takes to launch them in a SpaceX Dragon capsule atop a SpaceX Falcon 9 rocket to the International Space Station.

“We cannot forget this is a test flight. This — is — a — test — flight,” he repeated. “We will go when everything is as safe as we can possibly make it.”

Forecasters put the odds of acceptable weather conditions Saturday at 50-50, with the outlook improving to 60% favourable on Sunday. Rain and clouds were the main concerns for both days.

While NASA urged spectators to stay home because of the pandemic, prime viewing spots at area parks and beaches were packed Wednesday. A weekend launch could draw even bigger crowds. The Kennedy Space Center Visitor Complex reopened Thursday, after a 2 1/2-month shutdown, and within a few hours, all 4,000 tickets were snapped up for Saturday’s launch attempt.

President Donald Trump and Vice-President Mike Pence were expected to return for the Saturday attempt. The number of employees, journalists and guests inside remained extremely limited because of the pandemic.

Whether an attempt is made Saturday or Sunday, “There will be no pressure. We will launch when we’re ready,” Bridenstine said.

The last time astronauts launched to orbit from the U.S. was in 2011 when Atlantis closed out the 30-year space shuttle program. Hurley was on that mission as well.

NASA hired SpaceX and Boeing in 2014 to get the ball rolling again — kicking off a commercial revolution for getting people to low-Earth orbit, according to officials. In the meantime, NASA has spent billions of dollars to buy seats on Russian Soyuz capsules for U.S. astronauts, in order to keep the space station staffed.

Boeing’s first astronaut flight, on the company’s Starliner capsule, is not expected until next year.

Bridenstine offered high praise for Musk on Friday and all his personal touches: spiffy spacesuits, Tesla rides to the launch pad, a colour-co-ordinated rocket and capsule — and more.

Musk has brought “vision and inspiration” to the American space program, Bridenstine said. While there’s occasionally a little tension between NASA and SpaceX, “he gives me a commitment and he delivers on that commitment. That has happened every single time.”

——

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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Proxima b, a confirmed — potentially habitable — Earth-sized planet, is a mere 4.2 light years away – The Post – Ontario

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At 1.17 Earth masses and in the habitable zone, scientists says it’s orbiting the nearest star to our sun

An artist’s depiction of what the surface of Proxima b might look like.

ESO

A team of scientists from the University of Geneva has confirmed the existence of an Earth-sized planet orbiting the star closest to the sun. The planet, called Proxima b, is 1.17 times the mass of Earth and is located in the habitable zone of Promixa Centauri, 4.2 light years away.

Because Proxima Centauri is a red dwarf, much smaller and cooler than the sun, its habitable zone or Goldilocks zone — neither too hot nor too cold for liquid water to exist — is very close to the star. Proxima b orbits about 20 times closer to its star than Earth does to the sun, and a year on the planet is just over 11 Earth days long.

Red dwarf stars emit huge quantities of X-rays, and the scientists estimate the planet gets 400 times as much radiation as Earth. But Christophe Lovis, a researcher in the astronomy department of the university, was optimistic that this might not rule out the possibility of life, or at least habitability.

“Is there an atmosphere that protects the planet from these deadly rays?” he asks. “And if this atmosphere exists, does it contain the chemical elements that promote the development of life — oxygen, for example? How long have these favourable conditions existed?”

Proxima b could have a moon-sized neighbour.

Such questions will, he hopes, be answered in the next few years by the next generation of spectrometers, which will tease out data from the light of the star and its planet. The recent confirmation of Proxima b came from data from a spectrograph called ESPRESSO (Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations) mounted on the Very Large Telescope (yep, that’s its name) in Chile.

Proxima b was first detected by an earlier instrument called HARPS, or High Accuracy Radial Velocity Planet Searcher. “We were already very happy with the performance of HARPS, which has been responsible for discovering hundreds of exoplanets over the last 17 years”, says lead researcher Francesco Pepe. “We’re really pleased that ESPRESSO can produce even better measurements.”

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In addition, data from ESPRESSO included a second signal that could indicate yet another planet orbiting even closer to the star. “If the signal was planetary in origin, this potential other planet accompanying Proxima b would have a mass less than one third of the mass of the Earth. It would then be the smallest planet ever measured using the radial velocity method,” says Pepe. Proxima b could have a moon-sized neighbour.

Despite the relative nearness of Proxima Centauri as the sun’s closest stellar neighbour, we will have to rely on spectrographic data for the foreseeable future. Our fastest interplanetary probes, the Voyagers and New Horizons, would take tens of thousands of years to reach Proxima Centauri, even if they were headed in that direction. A plan called Breakthrough Starshot imagines a tiny probe travelling at 20 per cent of light speed, and making the journey in 20 years, but it’s still very much on the drawing board.

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