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Threatening our future in space – The Queens County Citizen

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Debris and non-functioning launcher steps in the geostationary ring. Aging satellites emit debris and explode due to residual energy sources. The resulting fragments can be thrown back and cross geostationary orbit. For this reason, the release of residual energy after the completion of the nominal mission is fundamental. ESA / ID & Sense / ONiRiXEL, CC BY-SA 3.0 IGO

Fragments of past space efforts are trapped in orbit around the Earth, threatening our future in space. Over time, the number, mass, and area of ​​these debris objects gradually increase, which increases the performance of the satellites.

The ESA’s Office of Space Debris constantly monitors the condition of these ever-evolving debris and publishes a current report each year. The condition of the debris atmosphere.

Since the beginning of the space age in 1957, tons of rockets, spaceships and equipment have been launched into space. Initially, they had no plan of what to do with them at the end of their lives. Since then, the numbers have continued to rise and millions of dangerous debris have formed from explosions and collisions in space.

Space Debris Danger

Despite advances in technology, the need to significantly increase the speed of understanding the space environment and implementing the proposed measures to reduce debris creation was recognized at the largest space debris conference ever held in Europe. Credit: ESA, CC BY-SA 3.0 IGO

“Explosions in orbit, the largest contributor to the current space debris problem, are caused by residual energy – fuel and batteries – onboard spacecraft and rockets. Despite years of efforts to prevent this, the number of such incidents has not decreased. Trends toward end-of-mission disposal are improving, but slowly, ”Said Holger Craig, head of the Space Safety Program.

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“In view of the constant increase in space-traffic, we must develop and provide technology to prevent debris mitigation efforts, and the ESA is doing so through its space safety program. In parallel, regulators need to monitor the status of space systems, as well as the global commitment to debris mitigation within their jurisdiction.

International guidelines and standards now exist, which clarify how we can achieve sustainable use of space:

  • Build rockets and spacecraft to reduce the amount of ‘shedding’ – the material is separated during launch and operation, due to the harsh conditions of space
  • Avoid explosions by releasing stored energy, the ‘passivating’ spaceship once in a lifetime
  • Move useless missions into the path of working satellites – by placing them in de-orbit or by moving them to ‘graveyard orbit’.
  • Avoid space hazards by carefully selecting orbits and performing ‘collision avoidance stunts’.

Many space agencies, private companies and other space actors are changing their behavior to adhere to these guidelines – but is it enough?

Worrying trends

Evolution in all orbits

The objects we send into orbit take up the same space as the debris they create. The growing area of ​​objects in space dramatically increases the probability of a collision. Red (PL) = payload; Orange (RB) = rocket body; Dark green (RM) = rocket mission related object. Credit: ESA

The number of debris objects, their composite mass and the total area they take up have been steadily increasing since the beginning of the space age. This is further fueled by the fact that a large number of spacecraft and rocket phases break down into orbit.

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The total area taken up by space debris is important because it is directly related to how many collisions we have in the future. As things stand, collisions between debris and working satellites are thought to outweigh explosions as a major source of debris.

No fragmentation events

There are many ways to create debris in space. Thousands of hazardous debris can be added to Earth’s orbit for each “fragmentation event”. Credit: ESA

Incidents that create debris have become commonplace

On average over the past two decades, 12 accidental ‘fragmentations’ have occurred in space each year – and this trend is unfortunately on the rise. Fragmentation events describe the moments when debris is created by collisions, explosions, electrical problems, and the separation of objects due to harsh conditions in space.

The bright side

Payloads clearance is low Earth orbit

More satellites or “payloads” sent into low Earth orbit are trying to adhere more consistently to debris mitigation than 20 years ago. However, progress is still very slow. Credit: ESA

Attempts to follow the rules (not yet matched)

Although not all satellites currently comply with international guidelines, most space actors are trying to comply with the regulations. Over the past decade, 15-30% of objects, or ‘payloads’ launched into non-compliant orbits in low-Earth orbit (excluding spacecraft for human spaceflight) have attempted to comply with debris mitigation measures. It was successful between 5% and 20%, reaching 35% in 2018 due to being in active orbit from the Iridium Alliance.

Rocket Bodies Clearance Low Earth Orbit

80% of rockets launched now attempt to clear low-Earth orbit – most of which successfully – more than just 20% at the turn of the millennium. Credit: ESA

More rockets are being safely disposed of

When it comes to rockets, most are consistently disposed of. Between 40 and 80% of those in non-compliant low-Earth orbit during this decade have attempted to comply with debris mitigation measures. Overall, it successfully cleared 30-70% of low-Earth orbit in naturally non-compliant rockets.

Of all the rockets launched in the last decade, 60-80% (in terms of mass) are committed to mitigation measures. Some rockets are in low-Earth orbit, which causes them to naturally decline in the Earth’s atmosphere, but a significant amount of rockets are redirected back into the Earth’s atmosphere, where they burn up or re-enter uninhabited areas. Such practices are on the rise, with 30% of rockets safely entering re-controlled mode from 2017 onwards.

This is very good news. Rocket bodies are one of the biggest objects we send into space and are at risk of getting caught in catastrophic collisions. A maximum of 24 hours after the launch, all measures must be taken to ensure that they are not delayed in orbit.

Payload launch traffic

Due to the increase in satellite constellations, the number of small satellites entering near-Earth orbit has increased dramatically in the last 10 years. Credit: ESA

Most satellites are in low altitude orbit, where they burn naturally

The amount of ‘small traffic’ into the low Earth orbit protected area – at an altitude of 2000 km – is changing significantly, especially due to the proliferation of smaller satellites and constellations.

Approximately 88% of the small payloads introduced in this region naturally adhere to space debris reduction measures because they are at low altitudes, i.e. they decompose in the Earth’s atmosphere.

It is estimated that between 30-60% of the total satellite mass (excluding human spaceflight) will adhere to life-end guidelines for the same reason.

“The rapid growth of satellites launched into low-Earth orbit is evident in our latest report,” explained Tim Florer, head of the ESA’s space debris office.

“We have observed fundamental changes in the way space is used. In order to continue to benefit from the science, technology and data that work in space, it is essential to achieve better compliance with existing space debris mitigation guidelines in spacecraft design and operations. This cannot be stressed enough – it is essential for the sustainable use of space. ”

Payload clearance near FEO

In recent years, all satellites in geostationary orbit have attempted to exit responsibly after reaching the end of their mission. Credit: ESA

High rates of debris reduction in geostationary orbit

Satellites launched into geostationary protection, at an altitude of 35,586 – 35,986 km, are much more likely to adhere to debris mitigation measures. Between 85% and 100% of those approaching the end of their lives this decade have tried to conform to these measures, of which 60 – 90% have been successful.

In geostationary orbit, operators have a clear commercial interest in keeping their routes away from useless satellites and debris – otherwise their spacecraft and bottom line could be in serious danger.

What now?

A systematic analysis of changing behaviors in space provides reasons to be cautiously optimistic when adopting debris mitigation measures – something that did not happen a decade ago.

If adapted quickly, continuous investment in new technologies to deactivate and dispose of missions will allow our environment to cope with the continuous growth of space traffic and more complex operations.

Space debris around the Earth

Distribution of space debris around the Earth. Credit: ESA

We must consider the space environment as a shared and limited natural resource. The continuous creation of space debris leads to Kessler syndrome, when when the density of objects in low Earth orbit is sufficient, the collision between objects and debris creates a cascade effect, each crash producing debris, which then increases the chance of further collision. At this point, some orbits around the Earth become completely homeless.

ESA is actively working to support guidelines for the long-term sustainability of outer space operations from the UN Committee on the Peaceful Uses of U-Space, funding the world’s first mission to remove part of the debris from orbit, internationally creating space sustainability rating and collision evasion automation. Since develops technology to reduce the impact on our environment.

The agency’s upcoming meeting on ESA’s space debris and clean space offices and the space debris – the largest in the world – is taking place in April 2021 as part of the space security program.

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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.

_____

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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U.S. spacecraft touches asteroid to grab sample – CBC.ca

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A NASA spacecraft descended to an asteroid Tuesday and, dodging boulders the size of buildings, momentarily touched the surface to collect a handful of cosmic rubble for return to Earth.

It was a first for the United States — only Japan has scored asteroid samples.

“Touchdown declared,” a flight controller announced to cheers and applause. “Sampling is in progress.”

Confirmation came from the Osiris-Rex spacecraft as it made contact with the surface of the asteroid Bennu more than 320 million kilometres away. But it could be a week before scientists know how much, if much of anything, was grabbed and whether another try will be needed. If successful, Osiris-Rex will return the samples in 2023.

“I can’t believe we actually pulled this off,” said lead scientist Dante Lauretta of the University of Arizona. “The spacecraft did everything it was supposed to do.”

Osiris-Rex took four and a half hours to make its way down from its tight orbit around Bennu, following commands sent well in advance by ground controllers near Denver.

Bennu’s gravity was too low for the spacecraft to land — the asteroid is just 510 metres across. As a result, it had to reach out with its 3.4-metre robot arm and attempt to grab at least 60 grams of Bennu.

‘Kissing the surface’

The University of Arizona’s Heather Enos, deputy scientist for the mission, described it as “kissing the surface with a short touch-and-go measured in just seconds.” At Mission Control for spacecraft builder Lockheed Martin, controllers on the TAG team — for “touch-and-go” — wore royal blue polo shirts and black masks with the mission patch. The coronavirus pandemic had resulted in a two-month delay.

Tuesday’s operation was considered the most harrowing part of the mission, which began with a launch from Cape Canaveral back in 2016.

A van-sized spacecraft with an Egyptian-inspired name, Osiris-Rex aimed for a spot equivalent to a few parking spaces on Earth in the middle of the asteroid’s Nightingale Crater. After nearly two years orbiting the boulder-packed Bennu, the spacecraft found this location to have the biggest patch of particles small enough to be swallowed up.

After determining that the coast was clear, Osiris-Rex closed in the final few metres for the sampling. The spacecraft was programmed to shoot out pressurized nitrogen gas to stir up the surface, then suck up any loose pebbles or dust, before backing away.

By the time flight controllers heard back from Osiris-Rex, the action already happened 18.5 minutes earlier, the time it takes radio signals to travel each way between Bennu and Earth. They expected to start receiving photos overnight and planned to provide an update Wednesday.

WATCH | A 3D animation of the asteroid Bennu:

The Canadian Space Agency’s OSIRIS-REx Laser Altimeter was crucial in mapping the asteroid Bennu ahead of its “touch-and-go” mission to collect samples that will be returned to Earth in 2023. Credit: Mike Daly, et. al 0:51

“We’re going to be looking at a whole series of images as we descended down to the surface, made contact, fired that gas bottle, and I really want to know how that surface responded,” Lauretta said. “We haven’t done this before, so this is new territory for us.”

Scientists want at least 60 grams and, ideally, closer to two kilograms of Bennu’s black, crumbly, carbon-rich material — thought to contain the building blocks of our solar system. Pictures taken during the operation will give team members a general idea of the amount of loot; they will put the spacecraft through a series of spins Saturday for a more accurate measure.

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.”

Another benefit: The solar-orbiting Bennu, which swings by Earth every six years, has a slight chance of smacking Earth late in the next century. It won’t be a show-stopping life-ender. But the more scientists know about the paths and properties of potentially hazardous space rocks like this one, the safer we’ll all be.

Osiris-Rex could make two more touch-and-go manoeuvres if Tuesday’s sample comes up short. Regardless of how many tries it takes, the samples won’t return to Earth until 2023 to close out the $800-plus million US quest. The sample capsule will parachute into the Utah desert.

“That will be another big day for us. But this is absolutely the major event of the mission right now,” NASA scientist Lucy Lim said.

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

NASA, meanwhile, plans to launch three more asteroid missions in the next two years, all one-way trips.

The team at Lockheed Martin Space in Denver, which built the spacecraft, react as contact with the asteroid Bennu is announced. (NASA TV)

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