It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Sunday, February 06, 2022
Ontario man finds an ice formation that looks like the Grim Reaper outside his home
With all the extreme weather alerts we've had, natural ice sculptures have started to form all over Ontario. From ice formations formed over rocks that look like jellyfish to trees covered in ice at a national park, there are a ton of these natural creations to see.
For one man in Ontario, he woke up to a bit of a terrifying surprise as he found an ice formation that looks like the Grim Reaper outside of his home.
On Feb. 28, 2020, Ben Tucci took a trip up to his cottage in Dunnville to check it out before demolition started and noticed something while walking towards the lakeside of the property.
As he grew closer, he was in awe, not believing what he was seeing. Massive ice sculptures had formed on his neighbour's lamp posts, creating figures that resembled the Grim Reaper and a woman.
"My immediate reaction of the dejected-looking figure was of an eerie looking woman or a sea hag of sorts, leaving the property almost as if to be walking away from Jack Frost," says Tucci about the figure.
Ben Tucci posted these eerie photos after a winter storm.
When he took a look at it a second time, the ice formation looked like Jack Frost, appearing to hold a cellphone.
Tucci posted the photos onto his social media with thousands of liking and commenting on the photo and sharing it to ghost social media sites.
The photos have caused quite a stir on social media, with a ton of people writing how terrified they would be if they saw the figure in person.
"I'm just saying that if I lived near there, I wouldn't be sleeping for the rest of the winter."
"These look like my imagining of the Ghost of Christmas Yet to Come," wrote another person.
There's a reasonable explanation to how these ghostly figures came about Ben says. With the frigid temperature, the winds blew the waves from Lake Erie over the floodwalls that hit the lamp posts to create them.
I don't know about you, but if I were to see these in person, I'd run as far and as fast as I can from these formations. These photos will be giving me nightmares for the next few days.
Meteorite Fragment Reveals an Extreme Asteroid Impact Hidden in Mars' Ancient Past
Mars meteorite NWA 7034, AKA 'Black Beauty'. (Institute of Meteoritics, UNM) SPACE
Evidence for an intense asteroid impact on Mars has been found in a Martian meteorite, which could alter the timeline for when the red planet might have been habitable.
In a famous meteorite named NWA 7034, or 'Black Beauty', scientists discovered a shocked crystal of the mineral zircon, showing a feature only seen on Earth in massive impact craters. This suggests that Mars was under heavy bombardment from meteorites later than thought.
"High-pressure shock deformation has not previously been found in any minerals from Black Beauty. This discovery of shock damage in a 4.45 billion-year-old Martian zircon provides new evidence of dynamic processes that affected the surface of early Mars."
NWA 7034, discovered in 2011 in the Sahara Desert of Morocco, is a 320-gram (11.3-ounce) chunk of volcanic breccia. That is, it's composed of pieces of different types of rock, a bit like a fruit cake.
It's mostly basalt, but it's scattered through with inclusions, including a number of crystals of zircon, and parts of it are up to 4.45 billion years old, nearly as old as the planet itself.
The early Solar System was a much wilder place than it is today. We've found evidence that, early on, the inner planets were absolutely pummeled by large asteroid impacts.
The overall absence of shock damage in the zircons from NWA 7034 was previously given as evidence that this intense period of bombardment on Mars had declined by about 4.48 billion years ago. Consequently, this could have meant that Mars was habitable quite early on.
Cox and her colleagues followed up by performing a close study of 66 grains of zircon found in NWA 7034, performing electron backscatter diffraction mapping and cathodoluminescence imaging to probe the structural arrangement of the atomic lattice within.
In just one of the 66 grains, one that was 4.45 billion years old, the team identified evidence of a massive impact.
"The type of shock damage in the Martian zircon involves 'twinning', and has been reported from all of the biggest impact sites on Earth, including the one in Mexico that killed off the dinosaurs, as well as the Moon, but not previously from Mars," Cox said.
In all minerals, atoms are arranged in a symmetrical three-dimensional lattice structure. Think of, for example, a lattice cube, where an atom sits at each corner of every cube in the lattice (although the actual structure varies significantly from mineral to mineral).
When high enough pressure is applied – 20 to 30 gigapascals, such as we see in the biggest asteroid impacts – something strange can happen to these lattices. Crystals can be pushed together so tightly that they end up sharing some of the points on their crystal lattices.
Although the team only found twinning in one of their zircon crystals, that one crystal suggests a formation process similar to what we have seen here on Earth, involving high pressure, likely from an asteroid impact. This, the researchers said, suggests that heavy bombardment on Mars was occurring at least 30 million years after the previous estimate.
In turn, this suggests that conditions may not have been amenable for life until a bit later, too – which coincides with the Mars timeline for another condition for life as we know it, the researchers say.
"Prior studies of zircon in Martian meteorites proposed that conditions suitable for life may have existed by 4.2 billion years ago based on the absence of definitive shock damage," says planetary geologist and geochemist Aaron Cavosie of Curtin University.
"Mars remained subject to impact bombardment after this time, on the scale known to cause mass extinctions on Earth. The zircon we describe provides evidence of such impacts, and highlights the possibility that the habitability window may have occurred later than previously thought, perhaps coinciding with evidence for liquid water on Mars by 3.9 to 3.7 billion years ago."
Given that prolonged heavy asteroid bombardment would have had the potential to vaporize any surface water and disrupt the atmosphere, though, perhaps that's not such a coincidence after all.
Are we alone in the Universe? Billions of dollars are being spent trying to answer that simple question. The implications of finding evidence for life beyond Earth are staggering. The “before and after” mark would punctuate human history.
Mars is currently the most popular exploration target to search for evidence of life elsewhere. Yet little is known about its early history. Our research on a Martian meteorite provides new clues about early surface conditions on the red planet.
Windows into the past
Today Mars is cold and inhospitable. But it may have been more Earth-like and habitable in a bygone era. Landforms on Mars record the action of liquid surface water, perhaps as early as 3.9 billion years ago.
Like Earth, early Mars was subject to a global bombardment from chunks of rock and ice floating around the Solar System. Giant impacts both destroy and create favourable environments for life. So to untangle when conditions suitable for life may have arisen on Mars, we have to track the history of both water and impacts.
A flotilla of rovers and orbiting spacecraft have been dispatched to Mars, with two NASA rovers specifically exploring impact craters for evidence of past life. Samples collected by rovers will be returned in future missions.
For now, meteorites are the only samples of Mars available to study here on Earth. Martian meteorites are born when an impact on Mars ejects rocky fragments that later intercept Earth's orbit. Most Martian meteorites are igneous rocks, such as basalt. One meteorite, NWA 7034, is different, as it represents a rare sample of the surface of Mars.
Sending shock waves
The NWA 7034 meteorite, weighing about 320g, was found in the desert of northwest Africa and first reported in 2013. Unique oxygen isotope signatures reveal its origin from Mars. Other meteorites blasted off of Mars during the same event have since been found.
NWA 7034 is a complicated rock made of broken rock and mineral shards called “breccia”. Its various fragments record different snippets of Martian history.
Tiny grains of the mineral zircon occur in NWA 7034. Zircon is a “geochronometer”, meaning it records (and reveals to us) how much time has passed since it crystallised from magma. Prior studies of NWA 7034 found it contains the oldest known zircons from Mars – some up to 4.48 billion years old.
Zircon is quite useful for studying meteorite impacts. It preserves microscopic damage caused by the passage of shock waves, and these “shocked grains” provide a solid record of impact. However, no zircons with definitive shock damage had been identified in previous studies of NWA 7034.
NWA 7034 is similar to a type of sedimentary rock on Earth called conglomerate. In such rocks, every mineral can have a different origin. With that in mind, we set out to survey additional zircon grains in NWA 7034 to see if we could find any that recorded evidence of impact.
We looked at more than 60 zircons, but found only one shocked grain. This means the impact occurred before the grain was mixed into the pile of fragments that became a rock. Reassessing Mars's timelines
The type of shock features we found are called “deformation twins”. High pressure shock waves squeeze zircon like an accordion. This process can reorganise atoms within the crystal, to form a duplicated “twin” of zircon, which we can detect.
We determined the zircon crystallised 4.45 billion years ago, making it one of the oldest zircons known from Mars – even older than the oldest known piece of Earth (also a zircon).
We don't know what kind of rock the shocked zircon originally formed in. The original igneous host rock was ripped apart during impacts on Mars. The zircon is a broken fragment from a larger grain mixed in with the matrix of the meteorite.
We do, however, know where shocked zircons like this are made. On Earth, shocked zircons with deformation twins are only found at impact craters. Moreover, they occur at all of Earth's largest asteroid strikes.
Zircons with shock features have been found at Vredefort in South Africa, Sudbury in Canada and Chicxulub in Mexico. The Mexican crater formed about 65 million years ago, and has been linked to the extinction of the dinosaurs. In this case, shocked zircons were one product of an impact large enough to cause a mass extinction.
Prior studies cited an absence of shock features in zircon from NWA 7034 to indicate a decline in catastrophic impacts on Mars by 4.48 billion years. It was further proposed that habitable conditions existed as of 4.2 billion years ago.
However, the shocked zircon we found crystallised 4.45 billion years ago. The shock event would have had to have occurred at least 30 million years after Mars had supposedly stopped being bombarded. When exactly was the impact?
Although determining the precise age of impact is difficult, geochemical studies of NWA 7034 reveal its main components were subject to meteorite impacts before roughly 4.3 billion years ago. In this scenario, the zircon may have been shocked during this time, somewhere between 4.3 and 4.45 billion years ago.
Alternatively, it may have formed more recently, but before a decline in the rate of impacts earlier than 3 billion years ago. Both land forms and water-bearing minerals argue for early surface water on Mars, possibly by 3.9 to 3.7 billion years ago. This may be the best indicator for when habitable conditions existed.
Our findings raise new questions about the early impact history of Mars. Determining the origin of the shocked zircon, and time of impact, will provide better context for interpreting the planet's history as archived in meteorite NWA 7034 – and potentially a timeframe for when conditions for life may have emerged.
PTI
Hydrogen transport proves viable but critics knock its ‘clean’ credentials
There have been some very valid concerns raised about the production process, but if the Hydrogen Energy Supply Chain (HESC) Pilot Project has proved anything, it is that transporting hydrogen over long distances is feasible.
The HESC project was first imagined about eight years ago by Japanese giant Kawasaki Heavy Industries and a consortium of industry partners from Japan and Australia including J-Power, Iwatani Corporation, Marubeni, Royal Dutch Shell, and Sumitomo Corporation.
According to J-Power non-executive director Jeremy Stone, the project was set up to prove a reliable, cost-effective supply chain of hydrogen as an alternative fuel to drive Japan’s economy as it transitions away from fossil fuels.
“Japan was going to go down the nuclear path to make sure it could reach net zero by 2050 targets but in 2011 Fukushima happened and they didn’t want to put all their efforts into nuclear,” he said.
“It was decided that hydrogen would be a very good, clean and alternative fuel to drive Japans economy – they were the first country to set up a hydrogen strategy in 2017, but they needed to prove they could actually do it.
“So, our project was set up to achieve that and our vision is to commercially produce carbon-neutral hydrogen through extraction from the La Trobe valley coal and biomass with carbon capture and storage,” he said.
Backed by the Federal and Victorian governments with cash injections of $50 million each, as well as funding from the Japanese government, the $500m pilot project uses lignite from AGL Energy’s newly constructed Loy Yang coal mine in the Latrobe Valley – alongside biomass, to create hydrogen with gasification technology.
Stone says the project has emitted around 580 cars worth of carbon, or 2,900 tonnes which have been offset through the purchase of Australian Carbon Credit Units (ACCUs).
Earlier this month, the Suiso Frontier graced Australian shores at Victoria’s Port of Hastings with a capacity of 250 cubic metres, equating to 75 metric tons of liquid hydrogen.
Stone said to date, “a small amount” – around one tonne of hydrogen had been extracted from a mix of coal and biomass and cooled to -253 degrees Celsius at the Hasting’s hydrogen liquefaction plant before it was transported to a purpose-built tank aboard the ship.
Now, the vessel has left Australian shores and is making its way to Kobe, Japan where the team will unload the liquified hydrogen into another purpose-built storage tank onshore.
Positive step VS black hydrogen reality
While it marked a significant moment for the HESC project, it also marked a significant moment for the world’s hydrogen industry, with the first fully integrated hydrogen energy supply chain realised.
But director of energy finance studies at the Institute for Energy Economics & Financial Analysis, Tim Buckley, says the move is a desperate, last attempt at trying to create value for a product that needs to stay in the ground.
“It is black hydrogen that is effectively produced by coal gasification – you might as well burn the coal itself,” he said.
“It is important we learn by doing, and the idea of the ship is good but hydrogen has to be transported at -250 degrees which is extremely energy intensive, even more than LNG at -160.
“There is nothing clean about it, that’s why Angus Taylor loves it.” Carbon capture and storage claims under fire
Nevertheless, Stone said if the project becomes commercial it will be paired with carbon capture and storage (CCS) technology developed by CarbonNet in Victoria.
“Rather than entering the atmosphere, CO2 emissions will be stored in rocks 1.5km beneath the Bass Strait,” he said.
“Over the last 10 years CarbonNet have been undertaking their own pilot testing as well – so these are two separate projects, but they are symbiotic and will be ready at the same time.”
And this is where the line gets conveniently blurred, Buckley says.
“CarbonNet have not sequestered a single unit of carbon dioxide in the 10 years that Victorian taxpayers have been funding it,” he said.
“This is a perfect example of the use of black hydrogen as a delaying tactic by dressing it up, trying to paint it blue, and pretending it’s clean and calling it clean hydrogen rather than blue because blue is hydrogen produced with gas from carbon capture and storage. “There is not a single carbon capture and storage project working in the world without massive subsidies.”
Or is CCS a critical step in the energy transition?
Chevron’s Gorgon LNG facility on Barrow Island, about 50km off Western Australia’s Pilbara coast, is one example of a failed CCS project, critics say.
While Chevron was meant to bury an average of 80 per cent of its (rather substantial) emissions over a five-year period from 2016, the system only started emissions storage in 2019 – and even after it came online, more issues ensued.
From Stone’s point of view, however, it’s a technology that has been around for 45 years and there are currently around 135 carbon capture and storage projects in various stages of development.
“When people mention Gorgon – the reality is, it hasn’t leaked any CO2,” he said.
“It has stored 5 million tonnes of CO2 which equals to the emissions of about 1 million cars.
“Yes, it hasn’t reached its annual storage target yet but it hasn’t leaked anything, and Chevron will eventually get their storage rate up.”
It is preposterous to think that, because Gorgon’s hasn’t achieved what it meant to, everyone needs to stop CCS, Stone explained.
“My view is that, if you are saying Gorgon proves it doesn’t work – to me it is like if you are building a tunnel project under the river and you encounter a problem, does that mean the world stops building tunnels?” he said.
“Everyone knows we need to do it, it is mind blowing,” he said.
“We can’t stop, we have such a major problem and in terms of CarbonNet it is incredibly close to where the hydrogen production is so it is cheap.
“There is huge storage capability in these depleted oil and gas reservoirs, we have already sucked out the oil and gas from these natural formations underwater and its basically reverse engineering where we will be pumping in liquid CO2 – completely different to what Gorgon does.”
The Morrison government has announced a further $7.5 million to support its pre-commercialisation phase and $20 million for the CCS project.
GREEN CAPITALI$M
Green Energy: Great Plains Institute identifies 14 locations across the US for hydrogen and carbon management hubs The 14 ‘most ideal locations’ were evaluated against a set of criteria that measured each regions pre-existing industrial and natural resources.
USA-based non-partisan energy research firm, Great Plains Institute has identified 14 optimal locations for future hydrogen and carbon management hubs across the US as an early step before the Department of Energy begins doling out billions of dollars from the Infrastructure Bill for hub funding.
The $8 billion allocated for future hydrogen hubs was provided by the Biden administration’s Infrastructure Investment and Jobs Act, which will support the creation of at least four regional hydrogen hubs.
The infrastructure bill also provided $12.1 billion to support new carbon management technologies, including money to build out regional CO2 transportation and storage infrastructure networks.
According to the institute, the 14 ‘most ideal locations’ were evaluated against a set of criteria that measured each regions pre-existing industrial and natural resources.
Regional opportunities for hub development. Pic: Great Plains Institute, S&P Global Platts
Each of the 14 locations “have a high concentration of industrial emitters, high fossil fuel use, facilities that qualify for 45Q tax credits, existing hydrogen and ammonia production”, the firm said, as well as large naturally occurring geologic formations for hydrogen or CO2 storage.
Regions are also evaluated for their existing commodity distribution infrastructure, such as highways, railroads, and waterways, and for their existing fossil fuel distribution infrastructure for hydrogen blending.
With all these ingredients, Great Plains Institute director of research Dane McFarlane said these hubs can achieve beneficial economies scale – “enabling investment breakeven for industrial capture retrofit and maximising the amount of carbon capture achieved.”
Emission Control: The global clean-energy transition hit a record breaking $755 billion investment during 2021
Off the back of rising climate ambition and policy action from countries around the world, research firm BloombergNEF says a new record $755 billion was invested into the low-carbon energy transition in 2021.
Clean power and electrification accounted for most of the investment, the firm said, recording $731 billion while hydrogen, carbon capture and storage, and sustainable materials made up the rest at $24 billion.
Pic: BloombergNEF
Investment rose in almost every sector covered in the report titled Energy Transition Investment Trends 2022, with carbon capture and storage (CCS) being the only sector to record a dip in investment, though there were many new projects announced in the year.
BloombergNEF head of analysis Albert Cheung said the global commodities crunch has created new challenges for the clean energy sector.
“This has raised input costs for key technologies like solar modules, wind turbines and battery packs,” he said.
“Against this backdrop, a 27% increase in energy transition investment in 2021 is an encouraging sign that investors, governments and businesses are more committed than ever to the low carbon transition and see it as part of the solution for the current turmoil in energy markets.”
While $755 billion is a massive number, US International Development Finance Corporation climate officer Jack Levine says that number needs to triple to $2.1 trillion per year between 2022-2025 to get on track for net-zero.
Regional and country leaders
Record amounts were invested in all three regions covered in the report: Asia Pacific (APAC), Europe, Middle East & Africa (EMEA), and the Americas (AMER).
APAC was both the largest region for investment at $368 billion (nearly half the global total), and the region with the highest growth at 38% in 2021.
Energy transition investment in EMEA grew by 16% in 2021, reaching $236 billion, while the Americas saw investment grow by 21% to $150 billion.
China was again the largest single country for energy transition investment, committing $266 billion in 2021.
The United States was in second place with $114 billion, though EU member states as a bloc committed more at $154 billion.
Germany, the UK, and France rounded out the top five countries for energy transition investment in 2021.
Asia-Pacific countries now hold four of the top 10 places in terms of energy transition investment levels, with India and South Korea joining China and Japan. New poll highlights ‘clean industries’ as the key to future prosperity
Around 60% of voters in Queensland and New South Wales believe the government’s top investment priority should be in renewables and say the states’ future economic prosperity lies in clean industries such as green hydrogen, critical minerals (lithium and cobalt), and manufacturing renewable products.
A new poll by the Climate Council of more than 2,000 voters in regional, rural, and metropolitan Queensland and New South Wales was released yesterday, highlighting that while both states dominate Australia’s coal exports, residents understand the ‘coal and gas’ era is coming an end.
Former Deloitte partner and leading economist Nicki Hutley said there is huge opportunity for the historical coal and gas heartlands of New South Wales and Queensland to grasp the economic rewards of the zero-emission transformation.
“Significantly, voters recognise that further cuts to carbon emissions – critical if we are to keep global warming in check – will increase jobs and lift economic growth,” she said.
“They also think regional areas will benefit the most, however, there is a strong view that there needs to be better support from government for communities that currently rely on fossil fuels in order for them to adjust to the changes.”
Solar installation. Pic: Climate Council
Solar PV, a renewable energy company designing and developing large-scale solar farms in Queensland based on the Sunshine Coast, said while the company was experiencing “a very exciting time in Queensland” it is also a “fork in the road” as far as renewable energy jobs go.
“What is missing is the Federal government – it needs to incentivise investment to create a real future for Queensland,” she said.
“It needs to provide a framework that can give investors certainty and improve the resilience and robustness of the grid.”
Overall, less than a quarter of respondents back fossil fuels as the best source of future jobs (27% in QLD and 19% in NSW) and only a quarter of voters in QLD and about one-fifth in New South Wales believe coal and gas lies in the state’s future. Utilising technology to increase distributed energy in low voltage networks
The Australian Renewable Energy Agency (ARENA) has seen the potential benefit of tech produced by Brisbane based company eleXsys Energy, which is designed to increase distributed energy resources (DER) hosting capacity on low voltage power lines.
Around $451,167 in funding has been invested to eleXsys Energy to demonstrate the potential of their new technology, eleXsys, which is a device that works by regulating voltage on low voltage power lines via dynamically providing or absorbing reactive power, for the benefit of new and existing DER customers where the device is installed.
By maintaining voltage within normal operating bands, eleXsys can better utilise DER, such as locally produced solar and battery storage, without expensive grid upgrades.
The $1.92 million trial will be undertaken in conjunction with local distribution network service provider (DNSP) Energy Queensland who will undertake testing of eleXsys at its Real Time Digital Simulator facility in Cairns to show how the device performs across a wider range of network types
.
eleXsys Energys’ device absorbs reactive power for the benefit of new and exiting distributed energy resources customers. Pic: eleXsys Energy
ARENA CEO Darren Miller said technology will play an increasingly important role in adding more renewables to our energy makeup.
“To help increase the amount of distributed energy we can have on Australia’s energy network, it’s vital that ARENA supports these new technologies such as the eleXsys which not only help to connect more home solar and batteries, but also helps to avoid expensive network augmentation works to support increased demand.”
eleXsys Energy will manufacture and install five eleXsys devices, with three being directly connected to Energy Queensland’s network, one being trialled behind the meter on a customer’s premises, and the other being used for testing at the Real Time Digital Simulator facility.
Kalina Power (ASX:KPO) was the biggest gainer this fortnight after releasing its quarterly update, where it said primary activities focused on the developed of its flagship 64MW primate site at the Kalina Energy Centre in Saddle Hills, Alberta.
The company’s Canadian subsidiary, KALiNA Distributed Power Limited (KDP) continued its engineering, contracting and regulatory approvals to position the project to achieve Full Notice to Proceed (FNTP).
KPO managing director Ross McLachlan said with the project essentially now shovel-ready, it is continuing efforts to ensure that the terms of the EPFC contract are suitable for project funding.
“To that end, we are considering various contracting strategies with our supply chain partners and Enerflex to achieve the right balance of price, risk and schedule that can work for all parties,” the company said.
PH2 is the second largest shareholder of H2X, which signed a binding agreement with Advik Hi-Tech, a global automotive components manufacturer.
The JV company will begin production of H2X’s Series of Fuel Cell Powered Generators. H2X currently has two of these units ready for deployment in Australia.
Up 5% this last fortnight was Leigh Creek Energy (ASX:LCK) after revealing it had achieved carbon neutral status at its Leigh Creek Urea Project in South Australia.
LCK managing director Phil Staveley said the company reached carbon neutrality eight years earlier than originally planned with working having started on Year 2 emission reduction programs.
Pilbara iron ore miner Fortescue Metals Group (ASX:FMG) is also up on the back of news that it has entered into a share sale and purchase agreement to acquire Williams Advanced Engineering Ltd (WAE).
WAE will be vertically integrated into Fortescue’s diversified resources and green energy business and will be managed via Fortescue Future Industries (FFI), Fortescue’s green energy and green technology division.
This acquisition of WAE provides critical technology and expertise in high-performance battery systems and electrification, FMG says, and will enable Fortescue to accelerate and support the decarbonisation of its mining operations.
(CNN)Three thousand miles off the coast of New Zealand and 2,000 miles north of Antarctica, Point Nemo is so far from land that the closest humans are often the astronauts on board the International Space Station -- that orbits 227 nautical miles above Earth.
It's precisely this remoteness that explains why the ISS, once it's retired in 2030, will end its days here, plummeting to Earth to join other decommissioned space stations, satellites and space debris. This is the world's space graveyard.
Spacefaring nations have been dumping their junk in the area around Point Nemo, named after Captain Nemo from Jules Verne's novel "Twenty Thousand Leagues Under The Sea," since the 1970s.
More than 263 pieces of space debris have been sunk in this area since 1971, including Russia's Mir space station and NASA's first space station Skylab, according to a 2019 study. They're not intact monuments to the history of space travel but are likely fragmented debris scattered over a large area.
"This is the largest ocean area without any islands. It is just the safest area where the long fall-out zone of debris after a re-entry fits into," said Holger Krag, Head of the Space Safety Programme Office at the European Space Agency.
Point Nemo is beyond any state's jurisdiction and is devoid of any human life -- although it's not free from the traces of human impact. In addition to the space junk on the seafloor, microplastic particles were discovered in the waters when yachts in the Volvo Ocean Race passed through the region in 2018. Best practice
Space junk such as old satellites reenter the Earth's atmosphere on a daily basis, although most of it goes unnoticed because it burns up long before it can hit the ground.
It's only larger space debris -- such as spacecraft and rocket parts -- that pose a very small risk to humans and infrastructure on the ground. Space agencies and operators must plan well in advance to ensure that it falls to Earth in this far-flung bit of ocean.
In the case of the International Space Station, NASA said the ISS will begin maneuvers to prepare for deorbit as early as 2026, lowering the altitude of the space lab, with it expected to crash back to Earth in 2031. The exact timings of the maneuvers depends on the solar cycle activity and its effect on Earth's atmosphere.
"Higher solar activity tends to expand the Earth's atmosphere and increase resistance to the ISS' velocity, resulting in more drag and natural altitude loss," NASA said in a newly published document outlining plans for decommissioning the ISS.
Space agencies and commercial operators must also notify authorities in control of flights and shipping -- usually in Chile, New Zealand and Tahiti -- of the location, timing and dimensions of the debris fall-out zones. Around two flights per day pass through the air space, said Krag. These authorities produce standardized message sent out to air and sea traffic.
A bigger problem than the spacecraft that end up in Point Nemo, said Krag, is chunks of metal rocket stages and spacecraft making what's known as an "uncontrolled reentry" into the Earth's atmosphere.
In June 2021, NASA criticized China for failing to "meet responsible standards" after debris from its out-of-control Long March 5B rocket plunged into the Indian Ocean. "Spacefaring nations must minimize the risks to people and property on Earth of re-entries of space objects and maximize transparency regarding those operations," said NASA Administrator Bill Nelson at the time.
The rocket, which was about 108 feet tall and weighed nearly 40,000 pounds, had launched a piece of a new Chinese space station into orbit on April 29. After its fuel was spent, the rocket had been left to hurtle through space uncontrolled until Earth's gravity dragged it back to the ground.
Krag said that, on average, 100 to 200 tons of space junk reenter the Earth's atmosphere in an uncontrolled way every year, yet most space experts consider reentry the most desirable outcome for space junk.
The vast majority stays above us where it can collide with functioning satellites, create more junk and threaten human life on crewed spacecraft.
There are at least 26,000 pieces of space junk orbiting the Earth that are the size of a softball or larger and could destroy a satellite on impact; over 500,000 the size of a marble big enough to cause damage to spacecraft or satellites; and over 100 million pieces of debris the size of a grain of salt that could puncture a spacesuit, according to a NASA report issued last year. Ocean trash can?
Landing space junk in the ocean depths of Point Nemo is the least worst option, said Vito De Lucia, a professor of law at the Norwegian Centre for the Law of the Sea at The Arctic University of Norway. However, we don't know much about the deep sea environment in this area.
Some research suggests that because of ocean currents in that region -- known as the South Pacific Gyre -- it is not particularly biologically diverse. Oceanographer Autun Purser, a postdoctoral researcher at the Alfred Wegener Institute in Bremerhaven, Germany, said he had been close the area and said the seafloor would likely be inhabited with sea cucumbers, seabed octopuses and "the odd fish."
"There is generally a low reign of food, as it is in the middle of the Pacific Gyre, a low productivity area with little upwelling nutrient rich waters, so though there will be seafloor animals, there will not be a high biomass down there probably," he said via email.
Krag at the European Space Agency said that the space objects that landed in the ocean were typically made from stainless steel, titanium or aluminum and were not toxic. "It is not more than a few dozens of metric tons per year. The re-entering fragments do not float, but sink and therefore are no hazard to ship traffic. Compared to the many lost containers and sunk ships, the amount of space hardware is vanishingly small." He noted that some rocket fuels are toxic but that they burn up during re-entry. Krag said that ESA was working on what he termed "design-for-demise" technology that would replace the aluminum, titanium and steel with materials that would melt during reentry.
International Space Station to Join Rest of Humanity’s Garbage at Bottom of the Ocean
NASA has announced that the International Space Station (ISS) will be retired in January 2031, at which point it will crash land into the ocean. The orbiting laboratory, which launched in 1998, will splash down at Point Nemo, a remote spot in the Pacific Ocean that is 1,678 miles from land, has been the site of many defunct satellites and man-made space detritus, earning it the nickname the “spacecraft cemetery”.
The ISS was a collaboration between NASA, the European Space Agency, Russia’s Roscosmos space program, the Canadian Space Agency and the Japan Aerospace Exploration Agency. Orbiting 227 nautical miles above Earth, the ISS has seen more than 200 astronauts from 19 different countries come aboard.
But NASA still has plans for the next decade of ISS. “The International Space Station is entering its third and most productive decade as a groundbreaking scientific platform in microgravity,” said Robyn Gatens, director of the International Space Station at NASA. “This third decade is one of results, building on our successful global partnership to verify exploration and human research technologies to support deep space exploration, continue to return medical and environmental benefits to humanity, and lay the groundwork for a commercial future in low-Earth orbit.”
Gatens added, “We look forward to maximizing these returns from the space station through 2030 while planning for transition to commercial space destinations that will follow.” Commercial space stations and space travel is clearly the wave of the future, as is the long heralded arrival of space tourism (for the obscenely wealthy at least).
“The private sector is technically and financially capable of developing and operating commercial low-Earth orbit destinations, with NASA’s assistance. We look forward to sharing our lessons learned and operations experience with the private sector to help them develop safe, reliable, and cost-effective destinations in space,” said Phil McAlister, director of commercial space at NASA Headquarters. “The report we have delivered to Congress describes, in detail, our comprehensive plan for ensuring a smooth transition to commercial destinations after retirement of the International Space Station in 2030.”
But de-orbiting the ISS will still be challenging, as it is the largest man-made object ever to occupy low-Earth orbit. Past uncontrolled deorbits have seen a scattering of space station parts across the ocean. And in 1979, the uncontrolled deorbit of NASA’s Skylab space station rained debris across Australia. No one was hurt, and Skylab became a pop culture punchline.
Opinion: DIY air purifier could be a solution in Quebec classrooms
Published Friday, February 4, 2022
Another push for school air purifiers
An air purifier can help clean the air at home.
Despite skyrocketing school COVID -19 cases since the January school reopenings, decades of negligence and no fix on the horizon for the critical school ventilation situation, the Quebec government of Francois Legault and its public health director are still shamelessly denying the scientific evidence linking COVID-19 transmission to inadequate ventilation and stubbornly refuting the data from peer-reviewed studies confirming the effectiveness of air purifiers in reducing airborne transmission. Why are school air purifiers so important?
For starters, 52,000 (58 per cent) of Quebec's 90,000 school classrooms and indoor spaces do not have any mechanical ventilation and most likely very few meet minimal international standards recommended in times of pandemic. Parents and teachers are left on their own to figure out how to reduce the risk of contagion in schools from inadequate ventilation systems.
It is a simple but extremely effective air-purifier made from low-cost materials readily available from local hardware stores.
The device is the brainchild of Richard Corsi, Dean of the College of Engineering at the University of California, Davis and an indoor air quality expert and Jim Rosenthal, CEO of Tex-Air Filters who tested it.
It has been nicknamed the Corsi-Rosenthal box (or CR box), costs less than $150 and can be built in less than an hour by anyone who has solid experience at cutting duct tape with a pair of scissors.
Best of all, a recent study has shown that it demonstrated exceptional performance relative to most commercially available air purifiers.
Corsi said that some homemade units are delivering up to 600 cubic feet per minute (CFM) in clean air delivery rates (CADR).
"That’s phenomenal", he said. "That’s actually better than a lot of the more expensive HEPA-based portable air cleaners".
Many underfunded school districts in several countries have turned this homemade technology into mass-production school and community events.
Students from a single classroom with a couple of parent volunteers can crank out a few dozen of those in a day, more than enough for the entire school.
It is a novel and rewarding way for students of all ages to integrate mathematics, science, art and writing skills into an exciting community project.
Theoretically, all Quebec classrooms could be equipped with CR boxes in 5-7 business days for about $20 million dollars, a fraction of the cost of equivalent commercial air-purifiers.
The Harvard School of Public Health and ASHRAE recommend targeting at least 5-6 air changes per hour (ACH) in classrooms for COVID-19 risk mitigation.
Note: this recommendation was made before recent, more transmissible variants, like Omicron.
It is fair to guess that extremely few Quebec classrooms come anywhere close to those levels, with the exception of those which have been fitted with air purifiers by the English school boards.
Using conservative estimates, two CR boxes per standard size classroom (1000 sq. ft. with an 8-foot ceiling) with 25 students could filter significantly more than six air changes per hour. In some areas like the nurse's station where symptomatic children may isolate, up to 10 air changes per hour are recommended.
Construction is amazingly simple; all you need is a 20-inch box fan, four 20x20 one-inch furnace filters rated no lower than MERV 13 (or the equivalent MPR 1900 rating), and some duct tape.
The CR box is also very eco-friendly, as the cardboard box from the fan can be used to make the bottom and the top of the device.
Although MERV-13 filters are not as efficient as HEPA-rated filters in filtering out COVID-19 viral-size particles which are around 0.1 micrometre, the virus is trapped in respiratory droplets that are predominantly 1 micrometre in size and larger.
Valuable information about the construction and other aspects of the CR-Box is available on this link.
It is unfortunate that Quebec did so little to improve inadequate school ventilation and that several English schools board had to fend for themselves to provide safe environments for their staff and children.
The English school boards could do so because they were protected by the Canadian constitution.
Sadly, French schools are not so lucky as they need to obtain government authorization to procure air purifiers, which is fiercely against their use.
People should not risk their lives to go to work.
CR boxes may not end the pandemic on their own, but along with other protective measures such as wearing N-95s or double masking, they do add an extra layer of protection terribly missing in Quebec schools.
The CR box is more than an air purifier: it is a powerful statement of community empowerment in response to this government's inept and harmful decisions.
NOW PLAYING Physicist Nancy Delagrave is one expert who signed an open letter urging Quebec to take aerosols seriously in classrooms. She explains why.
BP targeting renewable fuels and green hydrogen future for former Australian refinery
UK energy giant is just months away from entering FEED on its planned development to help decarbonise Western Australia’s largest industrial cluster Greener future: the BP oil refinery at Kwinana, Western Australia, shut down in 2021 after 65 years of operations Photo: BP
in Perth
UK supermajor BP is making steady progress with plans to produce renewable fuels and green hydrogen at a former oil refinery site in Kwinana, Western Australia.
Speaking at an Energy Club WA event this week in Perth, Justin Nash, senior manager City & Corporate Integrated Solutions at BP, told delegates that the company would be approaching the front-end engineering and design phase of the project within months. BP first flagged plans in September to repurpose the 65-year-old oil refinery to help decarbonise Western Australia’s largest industrial cluster.
BP intends to use the site, which is currently being used as a fuel import terminal, to use waste based feedstock to produce sustainable aviation fuel (SAF) and hydrogenated vegetable oil, otherwise known as renewable diesel.
“To produce these fuels will also need a source of hydrogen, and that will largely be generated from the pre-processing of these waste based feedstocks that will provide us some biogas to generate the hydrogen.” Article continues below the advert Renewable fuels demand
BP claims renewable fuels can deliver carbon emission reductions of up to 90% over fossil fuels, and the UK energy giant is considering similar plants at locations around the globe, however, Nash highlights that the Kwinana site is the only such facility BP is considering in a country that does not have a renewables fuel mandate.
Despite the lack of a mandate, BP believes it has identified demand for the lower emissions fuel within Australia.
“The future demand for renewable fuels is the transport sector, particularly heavy transport operators and miners that have a need to decarbonise with an interim solution before new technology is developed,” Nash explained.
“Aviation, one of the hardest to abate sectors, particularly when you consider long haul flights, and there’s a bunch of long haul flights from Australia.
“There’s a bunch of rail that connects across this country, it’s generally using diesel, so there’s an opportunity there to decarbonise. And then finally, with Kwinana, the opportunity for marine bunkering displacing current diesel to produce and use lower emission products.” Green hydrogen potential
BP has also partnered with the world’s largest infrastructure asset manager, Macquarie Group, to carry out a feasibility study into the potential to integrate green hydrogen production at the Kwinana site.
Nash explained BP intended to utilise power purchasing agreements from a renewable resource to power the electrolysers used to make the hydrogen.
GREEN VS BLUE
Blue hydrogen is produced from natural gas feedstocks, with the carbon dioxide by-product from hydrogen production captured and stored. However, the process is not emissions free.
Green hydrogen is made using electrolysis powered by renewable energy to split water molecules into oxygen and hydrogen, creating an emissions-free fuel.
One of the main goals of the feasibility study is to look at the aggregation of demand for clean hydrogen in the region.
He added this would then provide the opportunity for BP to aggregate demand from other sources in the Kwinana area and bring the benefits of economies of scale.
“We're targeting some of the best use cases for hydrogen, and that's places where it’s used today, industrial processes feedstock for chemicals, opportunities for decarbonised heat and energy that's currently being fulfilled by natural gas,” Nash explained.
“Transport, heavy duty long haul municipal fleets, waste trucks, community buses are all potential transport demand sources. And then with Kwinana’s access to fantastic pipeline infrastructure will have the opportunity to support WA’s target of 10% hydrogen blending [in the state’s gas grid] by 2030.” 'Regional powerhouse': BP sees Australia as ideal location for large-scale green hydrogenRead more
Grid stability
Nash also noted that the electrolyser could be used to contribute to grid stability and help with the “duck curve” challenge presented by WA’s increasing amount of rooftop solar.
The “duck curve” is a result of an increase in energy generation in the middle of the day from rooftop solar, at a time when demand is typically low as most people are not home. However, demand ramps up as people return home in the evening when solar generation is dropping.
BP could help the challenge of peak solar generation during day time, by ramping up a large load like an electrolyser.
Decarbonising Kwinana
Nash also explained how the transformed BP Kwinana site could help decarbonise the Kwinana industrial cluster, while adding to supply chain resilience.
“By leveraging this tremendous Kwinana industrial symbiosis, building on existing and enhancing common-user infrastructure such as a hydrogen backbone, we can support green industry and green manufacturing, not just in Kwinana, but one that can link with clean energy hubs throughout the state,” he said.
“We're starting with some demand, we have ourselves, and we have a need for that hydrogen, where we produce the renewable fuel, so there's an opportunity for us to be the foundation, and then to actually go to our neighbours and say, who else needs some of this green hydrogen to help them decarbonise? And through that, we can hopefully get the economies of scale to the lowest cost and we can make this work.” West Australian government pledges fresh funds to develop state's hydrogen industryRead more
As BP moves through the FEED stage and towards an investment decision, Nash indicated that he would like to see more government support.
“It's fair to say that other countries have more advanced incentives for their projects. and that's just a reality of doing business, particularly when you're working with a nascent industry,” he said.
“So there’s lots of good examples out there of where there are different types of policy settings. But with Australia committing to net zero, all the states committing to net zero, I mean the fundamental target is set. It’s now about how you enable that through effective policy… to seize the opportunity, because it really is a big one… particularly if we want to be the green energy exporter, similar to we are today in LNG.”
23 September 2021 23:01 GMT 3 February 2022 0:49 GMT UPDATED 4 February 2022 12:31 GMT By Josh Lewis
Information batteries: the latest proposal to dethrone lithium-ion batteries MINING.COM Staff Writer | February 4, 2022 | Binary code. (Reference image by Christiaan Colen, Flickr).
Researchers at the University of California – San Diego are proposing the idea of “information batteries” that store surplus renewable energy as computations to deal with the intermittency of wind and solar energy sources while cutting high costs associated with lithium-ion batteries and pumped hydro.
In a paper published in ACM Energy Informatics Review, the researchers explain that the issue of intermittency is being so poorly managed that in many places renewable energy is dumped during times of excess production, while at other times, power plants burn fossil fuels to meet grid shortfalls.
“The way things are going, in five years, the amount of renewable power wasted in California each year will be equivalent to the amount of power LA uses each year,” Barath Raghavan, co-author of the study, said in a media statement.
In Raghavan’s view, this state of affairs means that information batteries may have a role to play in countries’ greener future.
How they work
The main principle behind these devices is that when renewable energy is available in excess, it is used to speculatively perform computations in large, energy-intensive data centers. These data centers—from Google and Facebook to Hollywood movie rendering—consume 10 to 50 times the energy of a typical commercial building, according to the Office of Energy Efficiency and Renewable Energy. The stored computed results can then be used later when green energy is less plentiful.
“We had the observation that if we can predict possible computations that might occur in the future, we can do those computations now, while there is energy available, and store the results, which now have embodied energy,” Raghavan said.
As an example, the scientist mentioned that every day, YouTube data centers transcode more than 700,000 hours of videos to different resolutions. Many of these computations are predictable and can be performed at a time when there is excess green energy. At this point, the data is stored on servers for later use, when there is less renewable energy available on the grid — essentially moving electricity consumption from one time period to another.
In the scientific sense, Raghavan explained that batteries are stores of potential energy to do useful work, electrical or otherwise. Most storage of energy into batteries converts one type of energy into another kind of potential energy, for instance, electrical into gravitational. In this case, information provides energy in the same way as a battery because electrical energy is turned into what might be called “informational potential energy.”
Flexible system
In addition to taking advantage of task predictability, the system is also flexible: the computations that are completed in advance do not need to match exactly with the computations completed at a later time.
“We support pre-computing many fragments of computation and then later can pick and choose small pieces of computation done before, like puzzle pieces, and assemble them together to quickly compute a totally new computational task,” the researcher said.
For certain types of workloads, the information battery system is expected to offer better efficiency than lithium-ion batteries. The specific efficiency depends on multiple factors, such as the types of computation conducted and the predictability of power. But unlike lithium-ion batteries, storing data is cost-effective in terms of both money and energy.
While the idea itself is relatively simple, its proponents said that the challenge is determining what computation to perform, where and when, and how these computations should be done to efficiently retrieve the results later.
Raghavan and co-author Jennifer Switzer tackle those challenges by providing a design and proof of concept implementation of the zero-carbon system that includes recurrent neural networks for predicting the future availability of renewable energy and upcoming tasks in data centers.
It also includes a cache where functions are stored and a modified compiler to automatically modify code to store and retrieve results. The infrastructure would be geographically distributed, comprising many small, distributed data centers, each located in a region of the country where wind or solar production is known to be high.
“With this system, companies would be using power that would have been dumped, and everybody else benefits because the grid operator doesn’t have to spin up natural gas power in the evening hours to compensate for demand,” Raghavan said.
THIS MARTIAN COLONY CONCEPT IMAGINES WHAT SUSTAINABLE OFF-PLANET HOUSING COULD LOOK LIKE
Establishing a new human colony on another planet is an opportunity to apply new designs. More importantly, however, it’s also an opportunity to learn from humanity’s past mistakes in building habitats.
Although we have yet to fully conquer the moon or even our oceans, some people are already eyeing Mars as our backup Earth. Of course, the planet is completely uninhabitable in its current state, but there is no shortage of ideas on how to make human life possible on the red planet. Some ideas involve radical terraforming, while others try to limit the changes inside enclosed structures. One concept, in particular, tries not to repeat the sins of the past and make use of Mars’ natural landscape rather than go against it.
Designers: Burak Celik, Naz Kaplan and Zeynep Ege Odabasi.
Of course, we can’t fault our ancestors for not knowing better, but that is also why we have to make sure we don’t make the same mistakes when trying to extend our civilization’s reach to other planets. This architectural design concept doesn’t focus as much on the technologies that will make human, animal, and plant life possible but on making sure we don’t change the face of our new home as we did the old one. In particular, the donut-shaped colony is designed to take advantage of the Martian landscape instead of trying to mold it to our needs.
Genesis v.2, as the prototype is called, is designed to sit on the edge of craters rather than on more level surfaces that may be a rarity on Mars. This has two advantages, one being that the colony could actually protect itself from radiation without having to dig more holes on the already battered face of the planet. It offers an opportunity to start off on the right foot with sustainable structures, ensuring that Mars will survive longer than our Earth.
The design of Genesis v.2, however, is also adjustable and relocatable so that expanding the population doesn’t require establishing another colony. The radius of the ring could be expanded to accommodate more units, for one. If necessary, however, the central production and circulation tower could also be relocated to a different crater that can support an even bigger ring.
On the inside, the predominantly white motif of the housing prototype definitely gives off futuristic vibes, the clean and blemish-free walls contrasting sharply with the red, barren wastelands outside. From the outside, Genesis v.2 ironically looks incomplete, but that’s an intentional design choice to represent and remind us of humanity’s always incomplete knowledge, especially when establishing a colony on an alien planet.
Origin of Supermassive Black Hole Flares Identified: Magnetic “Reconnection” Near the Event Horizon
BySIMONS FOUNDATIONFEBRUARY 5, 2022
A top-down view of a black hole during the lead-up to a flare. Hot plasma initially flows into the black hole. As the magnetic field evolves, this flow reverses and launches some material outward. That accelerated material generates the flare. Credit: B. Ripperda et al., Astrophysical Journal Letters 202
Largest-ever simulations suggest flickering powered by magnetic ‘reconnection.’
Researchers at the Flatiron Institute and their collaborators found that breaking and reconnecting magnetic field lines near the event horizon release energy from a black hole’s magnetic field, accelerating particles that generate intense flares. The findings hint at exciting new possibilities in black hole observation.
Black holes aren’t always in the dark. Astronomers have spotted intense light shows shining from just outside the event horizon of supermassive black holes, including the one at our galaxy’s core. However, scientists couldn’t identify the cause of these flares beyond the suspected involvement of magnetic fields.
By employing computer simulations of unparalleled power and resolution, physicists say they’ve solved the mystery: Energy released near a black hole’s event horizon during the reconnection of magnetic field lines powers the flares, the researchers report in The Astrophysical Journal Letters.
The new simulations show that interactions between the magnetic field and material falling into the black hole’s maw cause the field to compress, flatten, break and reconnect. That process ultimately uses magnetic energy to slingshot hot plasma particles at near light speed into the black hole or out into space. Those particles can then directly radiate away some of their kinetic energy as photons and give nearby photons an energy boost. Those energetic photons make up the mysterious black hole flares.
A snapshot from one of the new black hole simulations. Credit: B. Ripperda et al., Astrophysical Journal Letters 2022
In this model, the disk of previously infalling material is ejected during flares, clearing the area around the event horizon. This tidying up could provide astronomers an unhindered view of the usually obscured processes happening just outside the event horizon.
“The fundamental process of reconnecting magnetic field lines near the event horizon can tap the magnetic energy of the black hole’s magnetosphere to power rapid and bright flares,” says study co-lead author Bart Ripperda, a joint postdoctoral fellow at the Flatiron Institute’s Center for Computational Astrophysics (CCA) in New York City and Princeton University. “This is really where we’re connecting plasma physics with astrophysics.”
Ripperda co-authored the new study with CCA associate research scientist Alexander Philippov, Harvard University scientists Matthew Liska and Koushik Chatterjee, University of Amsterdam scientists Gibwa Musoke and Sera Markoff, Northwestern University scientist Alexander Tchekhovskoy and University College London scientist Ziri Younsi.
A top-down view of a black hole during the lead-up to a flare. Hot plasma initially flows into the black hole. As the magnetic field evolves, this flow reverses and launches some material outward. That accelerated material generates the flare. Credit: B. Ripperda et al., Astrophysical Journal Letters 202
A black hole, true to its name, emits no light. So flares must originate from outside the black hole’s event horizon — the boundary where the black hole’s gravitational pull becomes so strong that not even light can escape. Orbiting and infalling material surrounds black holes in the form of an accretion disk, like the one around the behemoth black hole found in the M87 galaxy. This material cascades toward the event horizon near the black hole’s equator. At the north and south poles of some of these black holes, jets of particles shoot out into space at nearly the speed of light.
Identifying where the flares form in a black hole’s anatomy is incredibly difficult because of the physics involved. Black holes bend time and space and are surrounded by powerful magnetic fields, radiation fields and turbulent plasma — matter so hot that electrons detach from their atoms. Even with the help of powerful computers, previous efforts could only simulate black hole systems at resolutions too low to see the mechanism that powers the flares.
Ripperda and his colleagues went all in on boosting the level of detail in their simulations. They used computing time on three supercomputers — the Summit supercomputer at Oak Ridge National Laboratory in Tennessee, the Longhorn supercomputer at the University of Texas at Austin, and the Flatiron Institute’s Popeye supercomputer located at the University of California, San Diego. In total, the project took millions of computing hours. The result of all this computational muscle was by far the highest-resolution simulation of a black hole’s surroundings ever made, with over 1,000 times the resolution of previous efforts.
The increased resolution gave the researchers an unprecedented picture of the mechanisms leading to a black hole flare. The process centers on the black hole’s magnetic field, which has magnetic field lines that spring out from the black hole’s event horizon, forming the jet and connecting to the accretion disk. Previous simulations revealed that material flowing into the black hole’s equator drags magnetic field lines toward the event horizon. The dragged field lines begin stacking up near the event horizon, eventually pushing back and blocking the material flowing in.
A snapshot from one of the new black hole simulations. Here, green magnetic field lines are overlaid on a map of hot plasma. Just outside the black hole’s event horizon, the connection of magnetic field lines pointing in opposite directions makes an X-point where they crisscross. This process of reconnection launches some particles in the plasma into the black hole and others into space, an important step in the generation of black hole flares. Credit: B. Ripperda et al., Astrophysical Journal Letters 2022
With its exceptional resolution, the new simulation for the first time captured how the magnetic field at the border between the flowing material and the black hole’s jets intensifies, squeezing and flattening the equatorial field lines. Those field lines are now in alternating lanes pointing toward the black hole or away from it. When two lines pointing in opposite directions meet, they can break, reconnect and tangle. In between connection points, a pocket forms in the magnetic field. Those pockets are filled with hot plasma that either falls into the black hole or is accelerated out into space at tremendous speeds, thanks to energy taken from the magnetic field in the jets.
“Without the high resolution of our simulations, you couldn’t capture the subdynamics and the substructures,” Ripperda says. “In the low-resolution models, reconnection doesn’t occur, so there’s no mechanism that could accelerate particles.”
Plasma particles in the catapulted material immediately radiate some energy away as photons. The plasma particles can further dip into the energy range needed to give nearby photons an energy boost. Those photons, either passersby or the photons initially created by the launched plasma, make up the most energetic flares. The material itself ends up in a hot blob orbiting in the vicinity of the black hole. Such a blob has been spotted near the Milky Way’s supermassive black hole. “Magnetic reconnection powering such a hot spot is a smoking gun for explaining that observation,” Ripperda says.
The researchers also observed that after the black hole flares for a while, the magnetic field energy wanes, and the system resets. Then, over time, the process begins anew. This cyclical mechanism explains why black holes emit flares on set schedules ranging from every day (for our Milky Way’s supermassive black hole) to every few years (for M87 and other black holes).
Ripperda thinks that observations from the recently launched James Webb Space Telescope combined with those from the Event Horizon Telescope could confirm whether the process seen in the new simulations is happening and if it changes images of a black hole’s shadow. “We’ll have to see,” Ripperda says. For now, he and his colleagues are working to improve their simulations with even more detail.
Reference: “Black Hole Flares: Ejection of Accreted Magnetic Flux through 3D Plasmoid-mediated Reconnection” by B. Ripperda, M. Liska, K. Chatterjee, G. Musoke, A. A. Philippov, S. B. Markoff, A. Tchekhovskoy and Z. Younsi, 14 January 2022, The Astrophysical Journal Letters. DOI: 10.3847/2041-8213/ac46a1
