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The First Arctic Summer Without Ice Is Coming in Just 15 Years – BNN

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(Bloomberg) — There’s a standard image of the Earth as seen from space that we carry in our heads: vast blue seas, green bands of forests, and frozen white caps on the top and bottom. By the summer of 2035, it may not be accurate. Scientists estimate that in just 15 years Arctic summer sea-ice could disappear for the first time since primitive humans left Africa. 

“The point is, this is happening soon,” says Maria-Vittoria Guarino, an Earth system modeler at the British Antarctic Survey and lead author of a study published earlier this month in the journal Nature Climate Change. “We will have less and less time to get ready for it, or less time to act upon it if we want to do something about it.”

The new research is the latest in a steady stream that has moved up the predicted timeframe for the ice-free Arctic milestone. The amount of sea-ice floating atop the Arctic Ocean at summer’s end has fallen about 13% per decade since 1979. The 13 years with the smallest ice extents on record have all happened over the previous 13 years—and this summer is a sure bet to be No. 14. 

The 2035 estimate made by Guarino and her colleagues is based on what’s known about past climates. Scientists over the years have assembled evidence about previous eras from chemical traces in ice, rocks, and sediment. The new Arctic study looks specifically at a period 130,000 years ago, called the Last Interglacial. 

That period was 4° Celsius hotter than than the pre-industrial era—a plausible preview of conditions humans are creating for the future. Current warming on average is already around 1°C, and the Arctic is warming more than twice as fast as the rest of the planet.

Guarino’s research joins a debate about the pace of global heating that has drawn in climate scientists this year. Some newly updated models, like the one Guarino’s team used, now suggest that warming will occur much, much faster than previously thought. There remains disagreement among scientists over modeling results that show accelerated warming. But, as Guarino sees it, the fact that at least one of these models with hotter-than-expected results has successfully matched physical evidence from the Last Interglacial period makes it difficult to dismiss the findings. Earlier climate models struggled to match the geological evidence from the Last Interglacial.

Estimates like these come with lots of uncertainty, which leaves open the possibility that ice may stick around longer, according to Zachary Labe, a postdoctoral researcher in Atmospheric Sciences at Colorado State University. “I’m also hesitant to focus on the year 2035 too much,” he says. “It’s challenging to predict the first ice-free Arctic.”

Scientists from North Carolina State University and the U.S. National Oceanic and Atmospheric Administration earlier this year used a different model to arrive at a similar 2035 target for the ice-free Arctic summer. By “ice-free,” scientists usually mean an extent of less than 1 million square-kilometers. The lowest it has reached is 3.4 million km² in 2012.

Ge Peng, research scholar on the North Carolina State University team, also noted that unexpected events could alter the timeline. The eruption of a large volcano, which spews chemicals into the atmosphere that block sunlight and lower temperatures, could push the estimates out a few years. 

Whichever summer is the first to lose its sea ice, Peng and her colleagues warn that businesses, governments, and people living in the Arctic need to prepare now for changes in regional geopolitics, transportation, and food availability.

Once the pandemic has lifted, Peng hopes to travel to the still-frozen Arctic and find it the way we imagine it with our eyes closed. “I want to do that soon,” she says, “because I don’t want the sea ice to be gone by the time I take the cruise.”

©2020 Bloomberg L.P.

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Air leaking from International Space Station but no danger to crew: Roscosmos agency – Reuters Canada

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Slideshow ( 2 images )

MOSCOW (Reuters) – The International Space Station is leaking air in above-normal volumes, but the leak presents no danger to the Russian-American crew, the Russian space agency Roscosmos said on Tuesday.

The leak has been localised to one section of a service module and the crew, made up of U.S. astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner, plan to eliminate it in the coming days, Russia’s RIA news agency quoted Roscosmos executive director Sergei Krikalev as saying.

Roscosmos said additional air may be delivered to the station.

Reporting by Polina Devitt; Writing by Olzhas Auyezov; Editing by Kevin Liffey

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Rare blue moon will bring a Halloween 2020 treat to the skies – CNET

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A brilliant full moon rises at NASA’s Kennedy Space Center in Florida in 2017.


NASA/Kim Shiflett

Another highly unusual event is headed our way in this bizarre year. The 2020 Halloween full moon will be visible to the entire world, rather than just parts of it, for the first time since World War II, astronomy educator and former planetarium director Jeffrey Hunt says. 

“When I was teaching, my high school students thought a full moon occurred every Halloween,” Hunt told me. Not quite, though pop culture decorations sure make it seem that way. The last Halloween full moon visible around the globe came in 1944, he said. He’s written about the event on his web site, When the Curves Line Up. There was a Halloween full moon for some locations in 1955, but that didn’t include western North America and the western Pacific, Hunt says.

While this year’s Halloween full moon will be visible in all parts of the globe, that doesn’t mean every single citizen will have a view. Residents across both North America and South America will see it, as will India, all of Europe and much of Asia. But while Western Australians will see it, those in the central and eastern parts of the country will not. 

Know time zones well? “Every time zone has it except those east of (GMT) +8 time zones if they have daylight time, or (GMT) +9 with no daylight time,” Hunt says.

Want to see the Halloween full moon? It’s so bright at the full phase it doesn’t matter if you’re in a crowded city or out on the farm. And you don’t need pricey equipment.

“Walk outside, and take a look,” Hunt says. 

Don’t be surprised, though, if you snap a Halloween moon shot with your phone and the photo doesn’t match what you saw.

“When the moon is photographed with a smartphone the results can be disappointing,” Hunt admits. “A telephoto attachment will help make the moon larger.  Be sure to check that the adapter fits on your make and model.  Also don’t overexpose the moon. Adjust the camera’s brightness so that features are visible and not blotted out by the moon’s brightness.” 

If you’re determined to get a good shot, Oct. 1 brings a full moon, so there’s time to practice. Because that makes two full moons in the same month, the Halloween full moon could also be known as a “blue moon.”

If you’re too busy watching horror movies (or doing whatever the coronavirus equivalent of trick-or-treating is), you’ll have to wait until 2039 for another global full moon.

“Of course, full moons occur in October during the intervening years, just not on Halloween,” Hunt says. And a Halloween full moon may appear in your region before then. It just won’t be seen around the world.

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‘Earthgrazer’ meteor filmed skimming Earth’s atmosphere and bouncing into space – Yahoo Canada Sports

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The earthgrazer streaked across the sky above Germany (ESA)
The earthgrazer streaked across the sky above Germany (ESA)
<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Cameras on Earth captured a rare sight, an ‘earthgrazer’, a meteoroid which skims Earth’s atmosphere before ‘bouncing’ back into space.&nbsp;” data-reactid=”23″>Cameras on Earth captured a rare sight, an ‘earthgrazer’, a meteoroid which skims Earth’s atmosphere before ‘bouncing’ back into space. 

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="This particular meteoroid got hair raisingly close, flying as low as 56 miles up, far below any orbiting satellites, before bouncing back out.” data-reactid=”24″>This particular meteoroid got hair raisingly close, flying as low as 56 miles up, far below any orbiting satellites, before bouncing back out.

The space rock whizzed through the night sky above Northern Germany and the Netherlands in the early hours of 22 September. 

A meteoroid is typically a fragment of a comet or asteroid that becomes a meteor (a bright light streaking through the sky) when it enters the atmosphere. 

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Read more: There might once have been life on the moon

Most of them disintegrate, possibly with pieces reaching the ground as meteorites.&nbsp;” data-reactid=”29″>Read more: There might once have been life on the moon

Most of them disintegrate, possibly with pieces reaching the ground as meteorites. 

Earthgrazers are a bit luckier, and don’t burn up, but bounce back out, only grazing the edges of our planet’s protective gassy shield.

Earthgrazers don’t happen very often, just a handful of times per year.

It was spotted by cameras in the Global Meteor Network, a project which aims to cover the globe with meteor cameras and provide the public with real time alerts, building a picture of the meteoroid environment around Earth.

“The network is basically a decentralised scientific instrument, made up of amateur astronomers and citizen scientists around the planet each with their own camera systems” explains Denis Vida, who founded it.

<p class="canvas-atom canvas-text Mb(1.0em) Mb(0)–sm Mt(0.8em)–sm" type="text" content="Read more: Exoplanet twice the size of Earth ‘could be habitable’” data-reactid=”34″>Read more: Exoplanet twice the size of Earth ‘could be habitable’

“We make all data such as meteoroid trajectories and orbits available to the public and scientific community, with the goal of observing rare meteor shower outbursts and increasing the number of observed meteorite falls and helping to understand delivery mechanisms of meteorites to Earth”.

Tens of thousands of meteorites have been found on Earth, yet, of these only about 40 can be traced back to a parent asteroid or asteroidal source.

By better understanding these small bodies we are able to build up a more complete image of the Solar System, including potentially dangerous asteroids, meteor shower outbursts which could endanger satellites, as well as the chemistry and origins of our Solar System itself.

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