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The Unprecedented Ozone Hole Over The Arctic Has Closed Up – IFLScience

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The unprecedented Northern Hemisphere hole in the ozone layer has closed up after a month of lurking above the Arctic. 

However, this is no reason for humanity to start popping the champagne. The unusual ozone hole (and its recovery) had little to do with human activity or even changes in pollution levels from the Covid-19 lockdown, but a freakishly strong polar vortex around the North Pole.

Scientists from Copernicus Atmosphere Monitoring Service (CAMS) used data from multiple ozone observations satellites to confirm that the “unprecedented 2020 northern hemisphere #OzoneHole has come to an end,” according to an announcement on Twitter on April 23.   

“Although it looks like the polar vortex has not quite come to an end yet and will reform in the next few days, ozone values will not go back to the very low levels seen earlier in April,” they added

The ozone layer is a region of the stratosphere between 15 and 30 kilometers (9.3 to 18.6 miles) above Earth’s surface that has a high concentration of the gas ozone compared to other parts of the atmosphere. It effectively acts as a shield for our plant, absorbing much of the Sun’s harmful ultraviolet rays.

When you hear “hole in the ozone layer,” you most likely think about the ozone hole over the Antarctic in the South Pole. Scientists first documented the hole in 1985 and it quickly became associated with certain human-made chemicals, especially manufactured refrigerants and solvents, that can act as ozone-depleting substances after they are transported up into the stratosphere. Thanks to a huge global effort, called the Montreal Protocol, the hole in the ozone layer over the Antarctic is the smallest its been in decades.

The recent situation in the North Pole, however, is a little different. While we expect to see natural variations in the ozone layer with the changing of the seasons, March 2020 brought something much more extreme than usual. 

According to CAMS, the ozone hole was first opened over the Arctic in mid to late March after an unusually strong polar vortex, a low-pressure area that results in a wide expanse of swirling cold air. This trapped exceptional cold air in the North Pole for several weeks in a row and led to the formation of polar stratospheric clouds, high altitude clouds that can help to increase the chemical reactions involving the human-made chemicals that lead to ozone depletion once sunlight returns to the area. The result was dramatically dropping levels of ozone in the stratosphere in what became one of the largest ozone holes ever recorded over the Arctic. 

“From my point of view, this is the first time you can speak about a real ozone hole in the Arctic,” Martin Dameris, an atmospheric scientist at the German Aerospace Center in Oberpfaffenhofen, told Nature in late March. 

Now, it appears the polar vortex is starting to break down, allowing ozone-depleted air to mix around with ozone-rich air from lower latitudes. Since April 20, NASA’s Ozone Watch has show notable levels of ozone returning to the Arctic pole, and the stratosphere is starting to appear how you’d expect it to look during a typical April. 

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What a dinosaur's last supper reveals about life in the Cretaceous period – CBC.ca

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A beautifully preserved armoured dinosaur found in an Alberta oilsands mine died on a full stomach. The “extraordinarily rare” preservation of its last meal offers new clues and surprises about how the dinosaur lived during its last days.

The 5.5-metre-long, 1,300 kilogram spiky, plant-eating nodosaur, similar to an ankylosaurus but without a tail club, is the only known one of its species, Borealopelta markmitchelli. (Its name means “shield of the north” and honours Mark Mitchell, the technician who spent 7,000 carefully extracting the fossil from the surrounding rock). 

Victoria Arbour, an evolutionary paleontologist at the Royal BC Museum, describes how some armoured dinosaurs likely used their horns, spines and armour for fighting each other, not just for protection. 1:34

The nodosaur lived 110 million years ago during the early Cretaceous, in a lush forest of conifers, ferns and palm-like plants called cycads, near the coast of what was then an inland sea. At the time, the climate was warmer, similar to that of South Carolina, said Caleb Brown, a paleontologist at the Royal Tyrrell Museum of Paleontology in Alberta and lead author of the new study. It was published this week in the journal Royal Society Open Science.

The fossil was discovered by accident in 2011 by Shawn Funk, a shovel operator at the Suncor Millennium Mine near Fort McMurray. Paleontologists from the Royal Tyrrell were called to have a look and realized at once that it was no ordinary fossil.

While most fossils include only bones, this one included skin. It was so well-preserved that it has been described as “mummified.”

Meet one of the world’s best-preserved dinosaurs ever. Borealopelta fossilized so perfectly that we can see every inch of its armour and skin in 3D, 110 million years after its death. 0:58

In the dinosaur’s belly, “there were these massive concentrations of what looked like rocks,” Brown said.

Those were in a mass about the size of a soccer ball, and it appears they were gastroliths — rocks that some plant-eating dinosaurs use to grind up their food in their stomachs, as modern birds do, instead of using their teeth.

Sure enough, when chunks of the mass were encased in resin, sliced and examined under the microscope, the researcher could see well-preserved twigs, leaves, mosses, pollen and spores.

To get some help at identifying the plant material, the dinosaur researchers turned to paleobotanists, including University of Brandon researcher David Greenwood and his team, along with their retired Royal Tyrrell colleague Dennis Braman.

Inside the nodosaur’s belly was a mass about the size of a soccer ball that contained rocks. The rocks are called gastroliths and are used to grind up the animal’s food within its stomach. (Royal Tyrrell Museum)

Ferns and charcoal

They discovered that the dinosaur was a bit of a picky eater. While it lumbered through a landscape that was lush with conifers, horsetails and cycads, there weren’t a lot of those in its stomach.

“It’s almost all ferns,” Brown said, noting that ferns aren’t actually very nutritious. “It wasn’t just hoovering up everything on the landscape.”

But to him, the biggest surprise was that the stomach also contained a significant amount of wood, mostly charcoal, suggesting it was feeding in an area that had recently been ravaged by wildfires.

“And that’s a really cool result,” Brown said. “Because if you look at large mammals that are herbivores today, they often seek out areas that are recovering from forest fires.”

That’s because the new growth tends to be lush, more nutritious than older plants, and low to the ground where it’s easily accessible.

Microscope images show some of the plant material found inside the stomach, including a club moss spore sac (a), fern spore sacs (b-d), a charcoal fragment (e), parts of plant stems and leaves (f-l) and a cross section of a twig, showing its annual rings (m). (Brown et al/Royal Tyrrell Museum)

Forensic paleobotany

By looking at the types of spores and the fact that the twigs appeared to be in the middle of their growing season, the researchers figured out that the animal died during the wet season, which was late spring or early summer.

In Dinosaur Cold Case, a recent documentary about the fossil on CBC’s Nature of Things, Greenwood said extreme storms and flash floods would have been a problem at that time of year on the coastal plain where the dinosaur and suggested that being swept away by rushing water may have been what caused its death.

These are some plant fossils from Alberta from about the time that Borealopelta lived, including ferns, a gingko (d), horsetails (i) and a conifer cone (j). (Brown et al/Royal Tyrrell Museum)

The discoveries about the nodosaur’s last meal are significant because to date, Brown said, “we know almost nothing about what herbivorous dinosaurs eat.”

Only guesses can be made based on what plants lived nearby and the dinosaur’s teeth. There are also clues in fossil dinosaur feces, but the plant material in those are often digested beyond recognition and it’s difficult to know which dinosaur they came from.

Part of the problem is that finding preserved stomach contents from a dinosaur is “extraordinarily rare,” Jim Basinger of the University of Saskatchewan, a co-author of the study, said in a statement. 

Nine cases of possible dinosaur stomachs of plant-eating dinosaurs have been found, the researchers note, but most have turned out to just be plant material found nearby rather than actual stomachs. In this case, the dinosaur was washed far out to sea, without any plants from the landscape it lived in, before it was fossilized.

“So in this case we have what I would say is by far the best evidence that these are stomach contents,” Brown said.

That said, he notes that it may not necessarily be representative of what this species normally ate, as an animal’s diet can vary depending on its age, its health, and the seasonal availability of different foods.

Still, he said it’s useful to be able to compare it to what scientists think plant-eating dinosaurs were eating at that time and raises new questions to investigate, such as: How much of this food a dinosaur this size would have needed to eat to sustain itself? And how did it digest it?

 “I think give us a benchmark for figuring out how this animal may have lived.”

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‘Strawberry Moon’ to rise with a special eclipse for some skywatchers – Globalnews.ca

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The full moon on Friday, June 5 might look a little different in some parts of the world, where the so-called “Strawberry Moon” will fall partially under the Earth’s shadow.

The phenomenon, known as a penumbral lunar eclipse, occurs when the Earth comes between the sun and the moon, thereby casting a faint shadow on the moon. This penumbral lunar eclipse will make the full moon look slightly darker on part of its surface, although only some portions of the world will see it.

The penumbral lunar eclipse will only be visible from parts of Australia, Asia, Africa, Europe and South America, according to NASA’s charts.


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In other words, North Americans will need to watch a livestream on the internet to catch a glimpse of the event, which starts at 3 p.m. EDT. Nevertheless, the so-called “Strawberry Moon” will be visible to everyone.

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That name comes from the time of year and not the expected colour of the moon. There are farm-related nicknames for the first full moon of every month, and the strawberry nickname originated from the Algonquin First Nation, according to the Old Farmer’s Almanac. The first full moon of June often coincided with the harvest season for wild strawberries in North America, the Almanac says.


The Strawberry Moon is practically full over the horizon as a lady poses for a photo in Malaga, Spain, on June 4, 2020.


Jesus Merida/SOPA Images/LightRocket via Getty Images

Although skywatchers in Canada and the U.S. will miss out on this penumbral lunar eclipse, they’ll only have to wait a month to catch the next one. Another penumbral lunar eclipse is slated to happen on July 5, and that one should be visible from North America. The darkest penumbral lunar eclipse of the year is expected on Nov. 30.

A penumbral lunar eclipse also happened on Jan. 10, coinciding with that month’s “Wolf Moon.”

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0:59
Timelapse captures moment sky darkens for total solar eclipse


Timelapse captures moment sky darkens for total solar eclipse

Not to throw shade at the penumbral lunar eclipses, but they’ll likely pale in comparison to the annular solar eclipse predicted for June 21. That’s when the moon will pass between the Earth and the sun, making the sun look like a ring of fire for viewers in parts of Africa, China, northern India and Pakistan, according to TimeandDate.com.

Again, it won’t be visible from North America — but you’ll still be able to watch the whole thing online without risking eye damage from staring at the sun.

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© 2020 Global News, a division of Corus Entertainment Inc.

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In Space No One Can Hear You Campaign: Trump Team Pulls Ad – NDTV

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Donald Trump’s re-election campaign has pulled a video featuring the SpaceX launch and astronauts

Washington:

President Donald Trump’s re-election campaign has pulled a video featuring the SpaceX launch and astronauts which appeared to violate NASA’s media regulations, reports said.

The “Make Space Great Again” YouTube ad posted on YouTube showed footage from the Apollo program, as well as video of the landmark SpaceX Demo-2 mission and NASA astronauts Bob Behnken and Doug Hurley, the SpaceNews.com website said.

YouTube shows the video was removed by the uploader.

NASA generally allows use of its images and video but prohibits the use of its insignia and photographs of its astronauts in advertisements.

“As a government agency, NASA will not promote or endorse or appear to promote or endorse a commercial product, service or activity. Therefore, there are strict limits placed on the use of any of the NASA identities and emblem imagery in advertisements,” the space agency’s advertising regulations say.

“Astronauts or employees who are currently employed by NASA cannot have their names, likenesses or other personality traits displayed in any advertisements or marketing material.”

Hurley’s wife Karen Nyberg, a retired astronaut, and their young son were also reportedly shown in the clip.

“I find it disturbing that a video image of me and my son is being used in political propaganda without my knowledge or consent. That is wrong,” Nyberg tweeted.

A Change.org petition to “Stop Donald Trump politicizing SpaceX and NASA accomplishments” has attracted more than 6,000 signatures so far.

The New York Times described the video as “the latest effort by the president to parlay his stewardship of American space policy into an upbeat campaign issue.”

The SpaceX mission, which blasted off from Florida’s Kennedy Space Center on May 30, was the first crewed US spacecraft in nearly a decade.

Trump, who witnessed the liftoff, has relaunched the race to re-conquer the Moon and to journey onwards to the Red Planet.

But the deadlines — 2024 and 2033 respectively — appear unrealistic and have caused turbulence within the space agency.

(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)

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