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First images of magnetic fields at the edge of black hole in M87 Galaxy – McGill Newsroom

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The Event Horizon Telescope (EHT) collaboration, which includes researchers from McGill University, who produced the first ever image of a black hole, has revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarized light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.

“We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy,” says Monika Mościbrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud Universiteit in the Netherlands.

On 10 April 2019, scientists released the first ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole’s shadow. Since then, the EHT collaboration has delved deeper into the data on the supermassive object at the heart of the M87 galaxy collected in 2017. They have discovered that a significant fraction of the light around the M87 black hole is polarized.

“These diaphanous magnetic structures spread out from the black hole like the threads of a spider web – they are delicate looking but strong enough to trap plasma and prevent it from falling into this massive black hole,” said Daryl Haggard, from the McGill University Department of Physics. Her team, the McGill Extreme Gravity and Accretion group (MEGA), studies these and other physical phenomena that teach us about how black holes grow (and how they don’t grow) and thus how they impact their surroundings.

“This work is a major milestone: the polarization of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before,” explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the Universitat de València, Spain. He adds that “unveiling this new polarized-light image required years of work due to the complex techniques involved in obtaining and analysing the data.”

Light becomes polarized when it goes through certain filters, like the lenses of polarized sunglasses, or when it is emitted in hot regions of space that are magnetized. In the same way polarized sunglasses help us see better by reducing reflections and glare from bright surfaces, astronomers can sharpen their vision of the region around the black hole by looking at how the light originating from there is polarized. Specifically, polarization allows astronomers to map the magnetic field lines present at the inner edge of the black hole.

“The newly published polarized images are key to understanding how the magnetic field allows the black hole to ‘eat’ matter and launch powerful jets,” says EHT collaboration member Andrew Chael, a NASA Hubble Fellow at the Princeton Center for Theoretical Science and the Princeton Gravity Initiative in the USA.

The bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its centre are one of the galaxy’s most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets.

Astronomers have relied on different models of how matter behaves near the black hole to better understand this process. But they still don’t know exactly how jets larger than the galaxy are launched from its central region, which is as small in size as the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarized light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening.

The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetized gas can explain what they are seeing at the event horizon.

“The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon,” explains Jason Dexter, Assistant Professor at the University of Colorado Boulder, USA, and coordinator of the EHT Theory Working Group.

To observe the heart of the M87 galaxy, the collaboration linked eight telescopes around the world, to create a virtual Earth-sized telescope, the EHT. The impressive resolution obtained with the EHT is equivalent to that needed to measure the length of a credit card on the surface of the Moon.

This setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarized-light image clearly showing that the ring is magnetized. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration. The research involved over 300 researchers from multiple organizations and universities worldwide.

“The EHT is making rapid advancements, with technological upgrades being done to the network and new observatories being added. We expect future EHT observations to reveal more accurately the magnetic field structure around the black hole and to tell us more about the physics of the hot gas in this region,” concludes EHT collaboration member Jongho Park, an East Asian Core Observatories Association Fellow at the Academia Sinica Institute of Astronomy and Astrophysics in Taipei.

To read:

This research was presented in two papers published this week in The Astrophysical Journal.

  • Observational publication: First M87 Event Horizon Telescope Results. VII. Polarization of the Ring, ApJL March 24, 2021 [Preprint]
  • Theory publication: First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon, ApJL March 24, 2021 [Preprint]

The McGill research was funded by a Natural Sciences and Research Council of Canada (NSERC) Discovery Grant, a Fonds de recherche du Québec – Nature et technologies (FRQNT)Nouveaux Chercheurs Grant, and a Tier II Canada Research Chair.

More information

The EHT collaboration involves more than 300 researchers from Africa, Asia, Europe, North and South America. The international collaboration is working to capture the most detailed black hole images ever obtained by creating a virtual Earth-sized telescope. Supported by considerable international investment, the EHT links existing telescopes using novel systems — creating a fundamentally new instrument with the highest angular resolving power that has yet been achieved.

The individual telescopes involved are: ALMA, APEX, the IRAM 30-meter Telescope, the IRAM NOEMA Observatory, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope (LMT), the Submillimeter Array (SMA), the Submillimeter Telescope (SMT), the South Pole Telescope (SPT), the Kitt Peak Telescope, and the Greenland Telescope (GLT).

Visual Material Information

Image: Polarized emission of the ring in M87 – TIFF [10 Mb] – JPEG [8.8 Mb]

Short caption: Polarized view of the black hole in M87. The lines mark the orientation of polarization, which is related to the magnetic field around the shadow of the black hole. Credit: © EHT Collaboration


About McGill University

Founded in Montreal, Quebec, in 1821, McGill University is Canada’s top ranked medical doctoral university. McGill is consistently ranked as one of the top universities, both nationally and internationally. It is a world-renowned institution of higher learning with research activities spanning two campuses, 11 faculties, 13 professional schools, 300 programs of study and over 40,000 students, including more than 10,200 graduate students. McGill attracts students from over 150 countries around the world, its 12,800 international students making up 31% of the student body. Over half of McGill students claim a first language other than English, including approximately 19% of our students who say French is their mother tongue.

 

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Breathtaking NASA Image Shows a Magical ‘Sea of Dunes’ on Mars

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On Thursday, NASA released a stunning photo of a sea of dunes on Mars.

It also shows wind-sculpted lines surrounding Mars’ frosty northern polar cap.

The section captured in the shot represents an area that is 31 kilometers (19 miles) wide, NASA said. The sea of dunes, however, actually covers an area as large as Texas.

The photo is a false color image, meaning that the colors are representative of temperatures. Blue represents cooler climes, and the shades of yellow mark out “sun-warmed dunes,” the US space agency wrote.

Sea of dark dunes surrounds Mars’ northern polar cap.(NASA/JPL-Caltech/ASU)

The photo is made of a combination of images captured by the Thermal Emission Imaging System instrument on the Mars Odyssey orbiter, NASA wrote.

Captured during the period from December 2002 to November 2004, the breathtaking images have been released to mark the 20th anniversary of Odyssey.

The Mars Odyssey orbiter is a robotic spacecraft circling Mars that uses a thermal imager to detect evidence of water and ice on the planet.

It was launched in 2001, making it the longest-working Mars spacecraft in history.

Source:- ScienceAlert

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Humans actually hunted large animals and ate mostly meat for 2 millions years: study – CTV News

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TORONTO —
Despite a widespread belief that humans owe their evolution to the dietary flexibility in eating both meat and vegetables, researchers in Israel suggest that early humans were actually apex predators who hunted large animals for two million years before they sought vegetables to supplement their diet.

In a study recently published in the American Journal of Physical Anthropology, academics from Tel Aviv University in Israel and the University of Minho in Portugal examined modern biology to determine if stone-age humans were specialized carnivores or generalist omnivores.

“So far, attempts to reconstruct the diet of Stone-Age humans were mostly based on comparisons to 20th century hunter-gatherer societies,” one of the study’s authors, Miki Ben-Dor, a researcher at Tel Aviv University, said in a press release.

“This comparison is futile, however, because two million years ago hunter-gatherer societies could hunt and consume elephants and other large animals – while today’s hunter gatherers do not have access to such bounty.”

Instead, the researchers looked at approximately 400 previous scientific studies on human anatomy and physiology as well as archeological evidence from the Pleistocene period, or “Ice Age” period, which began about 2.6 million years ago, and lasted until 11,700 years ago.

“We decided to use other methods to reconstruct the diet of Stone-Age humans: to examine the memory preserved in our own bodies, our metabolism, genetics and physical build,” Ben-Dor said.

“Human behaviour changes rapidly, but evolution is slow. The body remembers.”

They discovered 25 lines of evidence from the studied papers on human biology that seem to show that earlier Homo sapiens were apex predators at the top of the food chain.

For example, the academics explained that humans have a high acidity in their stomachs when compared to omnivores or even other predators, which is important for consuming animal products.

“Strong acidity provides protection from harmful bacteria found in meat, and prehistoric humans, hunting large animals whose meat sufficed for days or even weeks, often consumed old meat containing large quantities of bacteria, and thus needed to maintain a high level of acidity,” Ben-Dor said.

Another piece of evidence, according to the study, is the structure of human fat cells.

“In the bodies of omnivores, fat is stored in a relatively small number of large fat cells, while in predators, including humans, it’s the other way around: we have a much larger number of smaller fat cells,” Ben-Dor said.

HUNTING EXPERTS

In addition to the evidence they collected by studying human biology, the researchers said archeological evidence from the Pleistocene period supports their theory.

In one example, the study’s authors examined stable isotopes in the bones of prehistoric humans as well as their hunting practices and concluded these early humans specialized in hunting large and medium-sized animals with high fat content.

“Comparing humans to large social predators of today, all of whom hunt large animals and obtain more than 70% of their energy from animal sources, reinforced the conclusion that humans specialized in hunting large animals and were in fact hypercarnivores,” the academics noted.

Ben-Dor said Stone-Age humans’ expertise in hunting large animals played a major role in the extinction of certain large animals, such as mammoths, mastodons, and giant sloths.

“Most probably, like in current-day predators, hunting itself was a focal human activity throughout most of human evolution. Other archeological evidence – like the fact that specialized tools for obtaining and processing vegetable foods only appeared in the later stages of human evolution – also supports the centrality of large animals in the human diet, throughout most of human history,” he said.

This is not to say, however, that humans during this period didn’t eat any plants. Ben-Dor said they also consumed plants, but they weren’t a major component of their diet until the end of the era when the decline of animal food sources led humans to increase their vegetable intake.

Eventually, the researchers said humans had no choice but to domesticate both plants and animals and become farmers.

Ran Barkai, one of the study’s authors and a professor at Tel Aviv University, said their findings have modern-day implications.

“For many people today, the Paleolithic diet is a critical issue, not only with regard to the past, but also concerning the present and future. It is hard to convince a devout vegetarian that his/her ancestors were not vegetarians, and people tend to confuse personal beliefs with scientific reality,” he said. 

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Marimaca Copper: First Drill Hole Intersects Broad Zone of Sulphide Copper Mineralization at Marimaca – Junior Mining Network

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VANCOUVER, British Columbia, April 07, 2021 (GLOBE NEWSWIRE) — Marimaca Copper Corp. (“Marimaca Copper” or the “Company”) (TSX: MARI) is pleased to announce the assay results of the first drill hole of a five-hole program targeting extensions of sulphide mineralization below the Company’s flagship Marimaca Oxide Deposit (“MOD”). Drilling encountered a broad zone of chalcopyrite and minor chalcocite, indicating potential for economic sulphide mineralization.

Highlights

  • Drill hole MAR-125 intersected 116m (expected approximate true width) at an average grade of 0.51% CuT from 162m, including two higher grade zones of:
    • 20m with an average grade of 0.77% CuT from 162m; and
    • 42m with an average grade of 0.92% CuT from 236m.
  • Intersection represents a significantly broader zone of mineralization than anticipated from earlier, nearby, sulphide drilling intersections
  • First drill hole of an initial five-hole campaign to test for extensions of mineralization at depth
    • First hole designed to extend mineralization closer to sulphide zones identified in historical drilling
    • Remaining four holes designed to test the limits of mineralization with step outs of approximately 300m at depth and between 400m and 700m along strike to the north and south of the first hole
  • Sulphide drilling to be completed shortly, with assay results on remaining holes expected by the end of April 2021
  • In response to escalating COVID situation in Chile, the Company has initiated a break in drilling which is not expected to impact the original target of testing all identified targets by the end of 1H 2021.

Sergio Rivera, VP Exploration of Marimaca Copper, commented:

“The results of the first hole of this initial campaign are extremely pleasing, exceeding both the widths and grades we had projected for this zone based on earlier drilling completed nearby. The broad intercept of chalcopyrite mineralization shows good continuity downhole, with potentially economic grades, especially at the bottom of the intercept.

“The drilling has also provided additional geological information, which we are using to refine our understanding of the controls of mineralization and to inform future drillhole locations, targeting mineralized extensions at depth and along strike.

“The next four holes are significant step outs from the known mineralized zones outside of the Mineral Resource Estimate area and are designed to test the limits of the mineralized body, both at depth and along strike. The second hole will be collared approximately 350m to the east of MAR-125, targeting mineralization up to 300m below the current deepest mineralization. The third, fourth and fifth holes will be located between 400m and 700m to the north and south of MAR-125, aiming to test for extensions along strike.

“This first hole has provided encouragement that there is potential for economically interesting sulphide mineralization at Marimaca, while the next four drill holes are designed to better delineate the tonnage potential of this.”

Discussion of Campaign Objectives and Results

The current five-hole drilling campaign at the Marimaca Copper Project is designed to test for extensions to mineralization below the MOD. Based on the structural controls of the mineralization, the results of previous geophysical campaigns and earlier drilling, which extended beyond the current Mineral Resource Estimate (“MRE”) area, the Company believes there is the potential for extensions of the mineralized body at depth across the full strike length of the MOD. All drill holes will be drilled at an azimuth of 270o and at -60o, roughly perpendicular to the north-south striking, easterly dipping mineralizing structures. Intercepts should, therefore, be relatively close to the true width of the mineralization.

The first drill hole (MAR-125) encountered a broad zone of dominantly chalcopyrite mineralization with some pyrite and minor chalcocite over a down hole width (expected to be equivalent to approximate true width) of 116m with an average grade of 0.51% CuT. This includes two zones of higher-grade mineralization including 20m with an average grade of 0.77% CuT and 42m with an average grade of 0.92% CuT at the end of the mineralized intercept. The hole was collared to test mineralization approximately 100m to the east of the earlier hole ATR-82, which intersected 44m of sulphide copper mineralization with an average grade of 1.05% CuT, and 200m and 300m east of holes ATR-93 and ATR-94 respectively, which both intersected mineralization with true widths of around 40m with average grades above 1.0% CuT. MAR-125 has demonstrated an extension to this higher-grade mineralization and provides further areas to target for follow up drilling.

MAR-125 is located in the center of the current MRE area, proximal to a zone of relatively high-grade sulphide mineralization intercepted in several drill holes over widths of between 30m and 50m. The remaining four drill holes have been located to test the limits of the mineralization by stepping out significantly at depth and along strike beyond the current MRE area. The collar of the second hole, MAS-03, is located approximately 100m to the south and 350m to the east of MAR-125 and is aimed to intersect mineralization approximately 300m below MAR-125. MAS-02 and MAS-04, located approximately 400m and 700m, respectively, south of MAR-125, and are planned as significant step outs along strike, targeting the conductivity high noted in the IP survey completed across the MOD

Figure 2

Sampling and Assay Protocol

True widths cannot be determined with the information available at this time. Marimaca Copper RC holes were sampled on a 2-metre continuous basis, with dry samples riffle split on site and one quarter sent to the Andes Analytical Assay preparation laboratory in Calama and the pulps then sent to the same company laboratory in Santiago for assaying. A second quarter was stored on site for reference. Samples were prepared using the following standard protocol: drying; crushing to better than 85% passing -10#; homogenizing; splitting; pulverizing a 500-700g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for CuT (total copper), CuS (acid soluble copper) by AAS. A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference.

Qualified Person

The technical information in this news release, including the information that relates to geology, drilling and mineralization was prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Marimaca Copper Corp, a geologist with more than 36 years of experience and a member of the Colegio de Geólogos de Chile and of the Institute of Mining Engineers of Chile, and who is the Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program.

Mr. Rivera confirms that he has visited the Marimaca Project on numerous occasions, is responsible for the information contained in this news release and consents to its publication.

Contact Information
For further information please visit www.marimaca.com or contact:

Tavistock
+44 (0) 207 920 3150
Jos Simson/Emily Moss 
This email address is being protected from spambots. You need JavaScript enabled to view it. 

Forward Looking Statements

This news release includes certain “forward-looking statements” under applicable Canadian securities legislation. These statements relate to future events or the Company’s future performance, business prospects or opportunities. Forward-looking statements include, but are not limited to, the impact of a rebranding of the Company, the future development and exploration potential of the Marimaca Project. Actual future results may differ materially. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Marimaca Copper, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: risks related to share price and market conditions, the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, the availability of and costs of financing needed in the future as well as those factors disclosed in the Company’s documents filed from time to time with the securities regulators in the Provinces of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador. Accordingly, readers should not place undue reliance on forward-looking statements. Marimaca Copper undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.


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