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Record-size ozone hole over Arctic now healed and closed – DW (English)



An “unprecedented” ozone depletion in the northern hemisphere has healed, but unlikely due to the impacts of worldwide coronavirus lockdowns, scientists say. The hole had been about three times the size of Greenland.

A “record-level” ozone hole over the Arctic – the biggest since 2011 –  has now closed, the UN World Meteorological Organization (WMO) said on Friday.

The phenomenon was driven by ozone-depleting substances still in the atmosphere and a very cold winter in the stratosphere — the layer of the earth’s atmosphere that lies between 10 and 50 kilometers (six to 31 miles)  above the earth — Reuters cited WMO spokeswoman Clare Nullis saying at a UN briefing in Geneva.

The image shows the Arctic ozone hole at its peak in March

“These two factors combined to give a very high level of depletion which was worse than the one we saw in 2011. It’s now back to normal again … the ozone hole has closed,” she said.

Scientists monitoring the hole at the Copernicus Atmospheric Monitoring Service (CAMS), a European Union earth observation program, announced the closure last week.

‘Unrelated to COVID’

Despite coronavirus lockdowns resulting in a significant reduction in air pollution, Nullies said the occurrence of the hole healing “was completely unrelated to COVID.”

CAMS also announced that the phenomenon probably had nothing to do with the pandemic.

“Actually, COVID19 and the associated lockdowns probably had nothing to do with this,” CAMS tweeted. “It’s been driven by an unusually strong and long-lived polar vortex, and isn’t related to air quality changes.”

Ten times the size of Greenland

A German scientist had detected the depletion only a month ago in what he said was the biggest hole in the ozone layer above the North Pole.

“In the areas where the thickness of the ozone layer is at its maximum, the loss is around 90%,” the German press agency dpa quoted Markus Rex — head of the department for atmospheric physics at the German Alfred-Wegener Institute — in March. It’s equivalent to an area three times the size of Greenland.

Read more: What happened to the ozone layer?

In total, an area of 20 million square kilometres, or 10 times the size of Greenland, is affected, even though the loss of ozone is sometimes lower.

Scientists from the European Space Agency (ESA) said that they had predicted the hole to heal as temperatures increased, breaking down the Arctic polar vortex and allowing ozone-depleted air to combine with ozone-rich air from lower altitudes.

According to recent data from the National Aeronautics and Space Administration (NASA), ozone levels above the Arctic reached a record low in March.

Separate from Antarctica ozone hole

The discovery of an ozone hole above Antarctica in 1985 led to the approval of the Montreal Protocol two years later,in which 197 countries agreed to phase out chemicals like chlorofluorocarbons to protect the ozone from further damage and decrease the size of the hole.

In 2019, it reached its smallest extent in about 30 years.
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SpaceX on the verge of sending astronauts into orbit – Financial Times



If Elon Musk’s SpaceX succeeds in sending two astronauts into orbit for the first time this week, it will do more than just boost the bragging rights of one of the world’s best-known billionaires.

As the first human test flight on a commercial rocket to reach the International Space Station, it will also signal a breakthrough for the private space industry as a whole, and an important moment in the opening up of low earth orbit to the commercial sector.

The first manned test for the Crew Dragon capsule, carrying two Nasa astronauts on top of one of SpaceX’s Falcon 9 rockets, is scheduled to lift off from the Kennedy Space Center in Florida on Wednesday morning.

If the flight to the ISS is successful, Nasa is expected to buy four seats on a follow-up flight later this year, the first time its astronauts will have become paying passengers on a commercially owned and operated space vehicle.

This week’s launch marks the moment when the private sector starts to lift humans off the face of the planet “reliably and cheaply”, said Peter Diamandis, founder of the X Prize, the competition which led to the first private manned flight to the edge of space 16 years ago. “It’s the first, fully commercially built, entrepreneurial capability,” he said. “What Elon Musk has done is nothing short of extraordinary, outpacing the US government-backed industries, Russia and China.”

Many of the technologies that SpaceX is relying on were pioneered by government space programmes over the past 60 years, meaning that the company is “standing on the shoulders of giants”, said Greg Autry, a former White House liaison to Nasa and an expert on the private space sector.

He compared the commercialisation of human space flight with the moment when the internet, which was created by the US Defense department, was handed over to the private sector. That makes the test flight a “tipping point we’ve been waiting for in the commercial space industry for a number of years”, he said.

Nasa, which commissioned both SpaceX and Boeing seven years ago to build human launch systems, is counting on commercial incentives and market competition to drive down the price of getting into space. It has estimated that the $400m SpaceX spent to develop its Falcon 9 rocket, which has become the workhorse for lifting cargo to the ISS, was only a tenth what it would have cost Nasa itself to build a similar rocket.

Since the Space Shuttle was retired in 2011 and the US was forced to buy seats on Russian rockets to propel its astronauts to the ISS, the cost of getting into space has risen sharply. Dennis Tito, the first space tourist, paid $20m in 2001 for a ride to the ISS on a Russian rocket. The price of a seat has now ballooned to more than $90m.

A competitive commercial market could quickly push that price back below $50m, said Mr Autry. Boeing’s rival space capsule suffered a setback earlier this year because of software glitches but is expected to make its first manned test launch next year. Other companies, including Jeff Bezos’s Blue Origin and Sierra Nevada, a Californian company that has built a space vehicle with wings, also hope to cash in.

As competition increases and the process for mounting human flights becomes more streamlined, the price for a trip into orbit could fall below $10m over the next decade, Mr Autry predicted.

All of this remains theoretical, however, until private companies prove they can launch humans into orbit safely, and return them to earth. The thought of entrusting astronauts to a fully commercial rocket company was jarring for many in the US space programme when it was first proposed in 2011, said Janet Kavandi, a former Nasa astronaut and now an executive at Sierra Nevada.

Nasa worked hard to make sure companies such as SpaceX are ready, she added. That meant doing everything from sharing the data from its Columbia shuttle disaster to teaching them everything it had learnt about crew survivability, down to the way seats are attached to the craft. By opting for a capsule, rather than a winged craft such as the Space Shuttle, SpaceX has also reduced the complexity of its launches.

Technical illustration showing some of the details of spaceX's Crew Dragon capsule and Falcon 9 launcher

Many in the private space industry believe demand is pent up to support the new human launch companies in their early years, though few are prepared to guess at the ultimate size of the market.

Countries that have space programmes but don’t have their own launch systems are already waiting to buy seats on private rockets, said Laura Forczyk at Astralytical, a US space consultancy. A boom in space tourism is likely to follow, she added, particularly if prices fall as fast as some expect.

Nasa, which objected to Mr Tito’s private flight nearly two decades ago, has since become a strong backer of space tourism as a way to share some of its own costs and shift more of its budget to reach the moon and, eventually, Mars. Last year it went as far as to publish a detailed price list for use of its facilities on the ISS, including $11,250 a day for private astronauts to access the station’s life support system and toilet.

The next step in commercialising space will need more accommodation for private astronauts, particularly since the ISS is due to be retired sometime this decade. The first private company to launch a module designed to attach to the ISS, Axiom, hopes to launch in 2024, on the way to a fully freestanding space station. The full potential of low earth orbit also depends on the private sector seizing on the chance to carry out materials research and manufacturing in zero-gravity — an idea that has barely been tested.

For Mr Musk, meanwhile, the first private trip some 250 miles up to the ISS is only a small step to a far more ambitious goal. Turning humanity into an interplanetary species is still his overriding ambition in life, said Mr Diamandis. “It means that we now have an entrepreneurial company that will also get us to the moon, and eventually to Mars,” he said.

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Excited Scientists Find ‘Cosmic Ring Of Fire’ Galaxy By Peering 11 Billion Light-Years Back In Time – Forbes



An Australian-led team of astronomers has unearthed a previously unknown type of galaxy just three billion years after the Big Bang. Variously described as both a “cosmic ring of fire” and a “titanic donut,” the finding could change what we know about how the first galaxies formed.

Announced today in the journal Nature Astronomy, this “collisional ring galaxy”—named R5519—is 10. billion light-years distant and the first of its kind found in the early Universe.

“It is a very curious object that we’ve never seen before,” said lead researcher Dr. Tiantian Yuan, from the Centre for Astrophysics and Supercomputing at Swinburne University of Technology, and the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D). “It looks strange and familiar at the same time.”

The publishing of Dr. Yuan’s paper, “A giant galaxy in the young Universe with a massive ring” was accompanied by an incredible video put together by Swinburne University’s astro-animator James Josephides.

Where is R5519?

R5519 is 10.8 billion light-years distant. It was imaged as it existed 11 billion years ago. Does that make it like “looking back in time?” Yes—all astronomy is looking back in time because the light that enters your eyes when stargazing/or a telescope has traveled vast distances through space at light-speed to reach us. Even sunlight is 8 minutes 20 seconds old.

The Big Bang took place around 13.8 billion years ago; R5519 was imaged just three billion light years later.

How big is R5519?

Supermassive. The hole in R5519’s “cosmic ring” has a diameter is two billion times that of the Earth-Sun distance, which astronomers call an astronomical unit (au), though the galaxy itself has a similar mass to our Milky Way.

R5519 is also three million times bigger than the diameter of the supermassive black hole in the galaxy M87, which was the first ever to be directly imaged last year.

MORE FROM FORBESHas NASA Found A Parallel Universe ‘Where Time Flows Backwards?’ The Truth Behind The Headlines

Why is R5519 such an incredible discovery?

This giant galaxy with a massive hole in the middle is a super-rare type of galaxy—a “collisional ring galaxy”—that could shake-up theories about how the earliest galaxies formed after the Big Bang, and how galaxies evolve. “It is making stars at a rate 50 times greater than the Milky Way,” said Dr. Yuan. “Most of that activity is taking place on its ring—so it truly is a ring of fire.”

How was R5519 discovered?

Working alongside colleagues from Australia, US, Canada, Belgium and Denmark, Dr. Yuan used spectroscopic data gathered by the W. M. Keck Observatory in Hawaii and images recorded by NASA’s Hubble Space Telescope to identify R5519’s unusual structure.

MORE FROM FORBESIs It Time To Dethrone The Big Bang Theory?

Why is R5519 such an important discovery?

R5519 is the first known “collisional ring galaxy” ever found in the early Universe, and it’s likely the result of a violent encounter with other galaxies. Its discovery has implications for understanding how spiral galaxies like our own Milky Way formed.

That’s because ring galaxies like R5519 are very rare in the local Universe. In fact, they account for a mere 0.01% of galaxies, and are formed by head-on collisions. This paper suggests that massive collisional rings are as rare 11.8 billion years ago as they are today.

“The collisional formation of ring galaxies requires a thin disk to be present in the “victim” galaxy before the collision occurs,” said co-author Professor Kenneth Freeman from the Australian National University. “The thin disk is the defining component of spiral galaxies: before it assembled, the galaxies were in a disorderly state, not yet recognisable as spiral galaxies.”

“In the case of this ring galaxy, we are looking back into the early Universe by 11 billion years, into a time when thin disks were only just assembling,” said Freeman. “This discovery is an indication that disk assembly in spiral galaxies occurred over a more extended period than previously thought.”

For comparison, the thin disk of our Milky Way galaxy began to come together only about nine billion years ago.

Wishing you clear skies and wide eyes.

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Telltale 'twist' points to the birth of a baby alien world – The Weather Network



Astronomers have made another stride forward in their quest to image the birth of a planet around another star directly.

For decades, scientists have been developing the basic ideas about how planets form around stars. First, a star forms from a collapsing cloud of gas and dust. The remaining material surrounding the star is spun into a disk by the star’s rotation, and parts of that disk clump together due to gravity. As these clumps gather more material to them, first planetesimals form, then protoplanets, and finally planets.

While this all makes sense, theoretically, these ideas still need to be verified by actual observations, and there are many details still missing from this model. Astronomers had to wait until 2018 for telescopes to improve to the point where they could start capturing images of protoplanetary disks. Until now, however, they still had not been able to focus in close enough to see an infant planet in the process of forming.

Over the past year, Anthony Boccaletti, from the Paris Observatory at France’s PSL University, led an international team in an attempt to do just that.

“Thousands of exoplanets have been identified so far, but little is known about how they form,” Boccaletti said in a European Southern Observatory (ESO) news release. “We need to observe very young systems to really capture the moment when planets form.”

Using the ESO’s Very Large Telescope (VLT), high up in the mountains of Northern Chile, Boccaletti and his team zoomed in on AB Aurigae, a young star in the constellation Auriga, located around 520 light-years away from Earth.

The ESO’s Very Large Telescope (VLT) beams a ‘guiding star’ laser up into the night sky, allowing its adaptive optics to take the clearest images of distant objects in space. Credit: ESO

Peering into the core of the AB Aurigae system, VLT captured the best images of the star’s planet-forming disk taken yet. Although they did not directly see a planet there, these images did capture the next-best thing.

AB Aurigae imaged by VLT SPHERE instrument eso2008aAB Aurigae imaged by the ESO’s SPHERE instrument. Credit: ESO/Boccaletti et al.

What we see here is an image captured by VLT’s Spectro-Polarimetric High-contrast Exoplanet REsearch instrument, also known as SPHERE. To produce this view of the system, SPHERE relies on a particular property of light to become ‘polarized’ as it reflects off a surface. SPHERE can apply various filters to collect the polarized light reflecting off dust grains and other objects surrounding a star. By doing so, it filters out all the unpolarized light being emitted directly by the star.

Thus, while a view like this would typically be completely washed out by the light from the star, SPHERE gives astronomers a detailed look without that bright interference.

AB-Aurigae-Planet-Forming-teaser-ESOThis VLT image for AB Aurigae reveals a bright ‘twist’ in the material around the star. Credit: ESO/Boccaletti et al./Scott Sutherland

By using SPHERE to observe AB Aurigae, Boccaletti and his team were able to resolve all the spirals of dense material (bright), and the darker gaps between those spirals.

In a particularly important find, though, they also spotted a bright ‘twist’ in the disk of material spiralling around the star, at roughly the same distance that Neptune orbits around the Sun. They identified this twist as the likely location of a planet in the process of forming.

As study co-author Emmanuel Di Folco of the Astrophysics Laboratory of Bordeaux (LAB) explained in an ESO press release, similar to a wave in the wake of a boat, this twist is a telltale sign that something big is moving through the gas and dust of this star’s protoplanetary disk.

AB-Aurigae-Planet-Forming-Spiral+Planet-eso2008cA larger view of the ‘twist’ reveals the spiral arms in more detail. The researchers also note a potential second planet in the view. Credit: ESO/Boccaletti et al./Scott Sutherland

“The twist is expected from some theoretical models of planet formation,” co-author Anne Dutrey, also with the Astrophysics Laboratory of Bordeaux, said in the press release. “It corresponds to the connection of two spirals – one winding inwards of the planet’s orbit, the other expanding outwards – which join at the planet location. They allow gas and dust from the disc to accrete onto the forming planet and make it grow.”

In the study, published in the journal Astronomy & Astrophysics, the researchers note that a second planet may be indicated in this view of AB Aurigae. It shows up as more of a ‘point source’, however, rather than another twist. They give a rough estimate that if this were another planet forming, it would likely be around three times the mass of Jupiter. The baby planet inside the ‘twist’ could be significantly larger, they say, with estimates of anywhere from 4-13 times Jupiter’s mass!

Astronomers will likely have to wait until the ESO completes their Extremely Large Telescope (ELT) in 2025 to revisit AB Augirae for a more detailed look. This current discovery is still significant, however. Not only will teach astronomers more about how alien exoplanets form, but it will help them to find even more of these baby planets in the making.

Sources: ESO | Phil Plait/Bad Astronomy/Syfy Wire | CBC

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