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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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NASA’s Europa Clipper will fly on SpaceX’s Falcon Heavy – The Verge

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NASA’s Europa Clipper will start its journey to Jupiter’s icy moon aboard a Falcon Heavy rocket built by SpaceX. NASA will pay SpaceX $178 million to launch the vehicle in October 2024.

The Europa Clipper got the green light from NASA in 2015. It will fly by the moon 45 times, providing researchers with a tantalizing look at the icy world, believed to have an ocean lurking under its icy crust. The Clipper is equipped with instruments that will help scientists figure out if the moon could support life.

For years, the Clipper was legally obligated to launch on NASA’s long-delayed Space Launch System (SLS). But with the SLS perpetually delayed and over budget, NASA has urged Congress to consider allowing the Europa Clipper to fly commercial. Switching to another vehicle could save up to $1 billion, NASA’s inspector general said in 2019.

NASA got permission to consider commercial alternatives to the SLS in the 2021 budget, and started officially looking for a commercial alternative soon after.

The SLS has powerful allies in Congress, who have kept the costly program alive for years, even as it blew past budgets and deadlines. The first flight of the SLS was originally supposed to happen in 2017. That mission — launching an uncrewed trip around the Moon — has since been pushed to November 2021, and keeping to that new schedule remains “highly unlikely” according to NASA’s Office of Inspector General, a watchdog agency.

SpaceX first launched its Falcon Heavy rocket in 2018, and started flying satellites in 2019. Earlier this year, NASA selected the rocket as the ride to space for two parts of a planned space station orbiting the Moon.

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Researchers Develop Genome Techniques to Analyze Adaptation of Cattle – AZoCleantech

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Jared Decker, a fourth-generation cattle farmer, has been aware of cattle suffering from health and productivity problems when they are moved from one location to another. The shift is from a region where they had spent generations to another place with a different climate, grass, or elevation.

Jared Decker is on a mission to help farmers learn more about what their cattle need to thrive. Image Credit: University of Missouri.

Decker, as a researcher at the University of Missouri, looks at the chances of using science to resolve this issue, thereby serving a dual purpose to enhance the cattle’s welfare and sealing the leak in an almost $50 billion industry in the United States.

When I joined MU in 2013, I moved cattle from a family farm in New Mexico to my farm here in Missouri. New Mexico is hot and dry, and Missouri is also hot but has much more humidity. The cattle certainly didn’t do as well as they did in New Mexico, and that spurred me to think about how we could give farmers more information about what their animals need to thrive.

Jared Decker, Associate Professor and Wurdack Chair, Animal Genetics, College of Agriculture, Food and Natural Resources 

The study was published in the journal PLOS Genetics on July 23rd, 2021.

Decker and his research team have revealed the proof exposing the fact that cattle are losing their key environmental adaptations. The researchers regard this as a loss due to the lack of genetic information available to farmers.

After assessing the genetic materials dating back to the 1960s, the team determined particular DNA variations linked with adaptations that could someday be used to develop DNA tests for cattle. These tests could help educate the farmers regarding the adaptability of cattle from one environment or another.

We can see that, for example, historically cows in Colorado are likely to have adaptations that ease the stress on their hearts at high altitudes. But if you bring in bulls or semen from a different environment, the frequency of those beneficial adaptations is going to decrease. Over generations, that cow herd will lose advantages that would have been very useful to a farmer in Colorado.

Jared Decker, Associate Professor and Wurdack Chair, Animal Genetics, College of Agriculture, Food and Natural Resources, University of Missouri

The research team included then-doctoral student Troy Rowan who had examined 60 years’ worth of bovine DNA data from tests of cryo-preserved semen produced by cattle breed associations. They observed that, as time runs, the genes related to higher fertility and productivity increased as a result of careful selection by farmers. Also, many genes relating to environmental adaptations have decreased.

According to Decker, the farmers are not to be blamed as there are no affordable methods available at present to identify the suitability of cattle for a specific environment. The study also proposes easy-to-use cattle DNA tests that focus on the particular adaptations identified in the study.

Such adaptations include resistance to vasoconstriction, which is a process of blood vessel narrowing that takes place at high elevation and puts excessive stress on the heart. Also creating resistance to the toxin in the grass can result in vasoconstriction and tolerance for increased temperature or humidity. All these factors tend to decline over generations when the cattle are shifted from the associated surroundings.

Sometimes, natural and artificial selection are moving in the same direction, and other times there is a tug of war between them. Efficiency and productivity have vastly improved in the last 60 years, but environmental stressors are never going to go away. Farmers need to know more about the genetic makeup of their herd, not only for the short-term success of their farm, but for the success of future generations.

Jared Decker, Associate Professor and Wurdack Chair, Animal Genetics, College of Agriculture, Food and Natural Resources

The first widely adopted genetic test for cattle was developed at the University of Missouri in 2007. Decker and Rowan are looking forward to giving further details of the development. Both the researchers grew up on farms with a desire to use research to help farmers to balance farm traditions of America with the requirement for eco-friendly business practices.

As a society, we must produce food more sustainably and be good environmental stewards. Making sure a cow’s genetics match their environment makes life better for cattle and helps farmers run efficient and productive operations. It’s a win-win,” concluded Decker.

Journal Reference:

Rowan, T. N., et al. (2021) Powerful detection of polygenic selection and evidence of environmental adaptation in US beef cattle. PLOS Genetics. doi.org/10.1371/journal.pgen.1009652.

Source: https://missouri.edu/

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'Eye of Sauron' volcano and other deep-sea structures discovered in underwater 'Mordor' – Livescience.com

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Researchers exploring the Indian Ocean have discovered the remains of a collapsed underwater volcano with an uncanny resemblance to the all-seeing “Eye of Sauron” from J.R.R. Tolkien’s famous fantasy series “The Lord of the Rings,” as well as two other seafloor structures named after places in Tolkien’s Middle-earth. 

The eye is actually an oval-shaped depression measuring 3.9 miles (6.2 kilometers) long by 3 miles (4.8 km) wide. Called a caldera, this giant divot is left over from the ancient collapse of a deep-sea volcano. The caldera is surrounded by a 984-foot-tall (300 meters) rim, giving the impression of eyelids, and an equally tall cone-shaped peak at the center, which looks like a pupil, according to The Conversation. The unusual structure is located 174 miles (280 km) southeast of Christmas Island ― an Australian external territory off mainland Australia ― at a depth of 10,170 feet (3,100 m).

A team of researchers discovered the structure while onboard the ocean research vessel Investigator, owned by Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO), on the 12th day of an expedition to Australia’s Indian Ocean Territories. The researchers used multibeam sonar to create 3D maps of the caldera and the surrounding seafloor.

Related: 5 colossal cones: Biggest volcanoes on Earth 

Like other calderas, this one formed when the peak of the original volcano collapsed, according to the researchers.

“The molten magma at the base of the volcano shifts upwards, leaving empty chambers [below],” chief scientist Tim O’Hara, senior curator at Museums Victoria in Australia, wrote in The Conversation. “The thin, solid crust on the surface of the dome then collapses, creating a large, crater-like structure.”

The area surrounding the volcanic crater is also home to two other noteworthy structures.

“Our volcanic ‘eye’ was not alone,” O’Hara wrote. “Further mapping to the south revealed a smaller sea mountain covered in numerous volcanic cones, and further still to the south was a larger, flat-topped seamount.”

Continuing the connection to Tolkien’s fantasy epic, the researchers named the cone-covered mountain Barad-dûr, after Sauron’s main stronghold, and the seamount Ered Lithui, after the Ash Mountains, both of which are found alongside the Eye of Sauron in the evil realm of Mordor. 

A map showing off the locations of all three features named after places in Mordor. (Image credit: 3D imagery courtesy of CSIRO/MNF, GSM)

The Ered Lithui seamount is part of a cluster of seamounts thought to date back about 100 million years, O’Hara wrote. The Ered Lithui seamount was once above the water’s surface, giving it its flat top, and it has gradually sunk to around 1.6 miles (2.6 km) below sea level.

Over millions of years, sand and sinking detritus — particulate matter, including plankton, excrement and other organic matter — have coated the seamount in a thick layer of sediment around 328 feet (100 m) deep. However, the caldera remains relatively uncovered, suggesting it may be significantly younger, O’Hara said. 

“This sedimentation rate should have smothered and partially hidden the caldera,” O’Hara wrote. It also “looks surprisingly intact for a structure that should be 100 million years old.”

This freshness suggests that the volcano was created, and subsequently collapsed, after the seamount began sinking into the ocean.

“It is possible that volcanoes have continued to sprout long after the original foundation,” O’Hara wrote. “Our restless Earth is never still.”

Originally published on Live Science.

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