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Population of endangered North Atlantic right whales continues to decline: study

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HALIFAX — A new study says the population of critically endangered North Atlantic right whales is continuing its downward trend.

The North Atlantic Right Whale Consortium says its latest estimate stands at 340 animals as of last year — a decline from 348 recorded in 2020.

The Boston-based consortium, which includes more than 200 conservation, government and industry organizations, says female right whales are getting smaller and are having fewer calves.

The consortium says only 15 calves were born in 2022, far below the average of 24 reported in the early 2000s.

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As well, the group determined there were no first-time mothers this season, which supports earlier research showing a downward trend in the number of female right whales capable of breeding.

Meanwhile, recent research has found evidence that the remaining whales are getting smaller, partly because of frequent entanglements in fishing gear, with smaller female right whales producing fewer calves.

Though the overall population decline has slowed, the number of right whales is now roughly the same as it was in 2001.

So far this year, there have been no detected right whale deaths, but scientists remain worried about the species — the most endangered large whales in the world.

“There has been a lot of focus on the fact that no right whale mortalities have been detected in 2022, which is certainly a good thing,” Scott Kraus, the consortium’s chairman, said today in a statement.

“While we can be cautiously optimistic about this, we know that only one third of right whale deaths are observed, so it is likely that some whales have died this year that were not observed. Additionally, we continue to see unsustainable levels of human-caused injuries to right whales.”

This report by The Canadian Press was first published Oct. 24, 2022.

 

The Canadian Press

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NASA's Artemis mission reaches farthest distance from Earth – CHCH News

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Orion has now traveled farther than any other spacecraft built for humans (Image courtesy/Johnson Space Center Flickr).

NASA’s Artemis mission reached its farthest distance from Earth on Monday.

Orion flew to its maximum distance from Earth during the Artemis I mission on flight day 13. It was 43,2210 kilometers away from our home planet.

Orion has now traveled farther than any other spacecraft built for humans.

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“It’s incredible just how smoothly this mission has gone, but this is a test. That’s what we do – we test it and we stress it,” NASA Administrator Bill Nelson said.

NASA says the un-crewed spacecraft remains in healthy condition as it continues its journey in distant retrograde orbit. Orion was cruising at 2702 kilometers per hour just before 8 p.m. on Monday.

The Orion spacecraft has now travelled beyond the moon and is officially on track to return to Earth (Brian Dunbar/NASA).

The mission is expected to last 25.5 days total and teams are already preparing for the spacecraft’s return.

NASA’s Exploration Ground Systems team and the U.S. Navy are already beginning initial operations for recovery of Orion when it splashes down in the Pacific Ocean.

The team will deploy Tuesday for training at sea before their return to shore to make final preparations ahead of splashdown.

Visit NASA’s real-time Orion tracker to follow the mission around the moon and back in real time.

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Cosmic Chocolate Pralines: Physicists’ Surprising Discovery About Neutron Star Structure – SciTechDaily

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The study of the sound speed has revealed that heavy neutron stars have a stiff mantle and a soft core, while light neutron stars have a soft mantle and a stiff core – much like different chocolate pralines. Credit: Peter Kiefer & Luciano Rezzolla

Physicists model more than one million equations of state to uncover other previously unexplained properties of neutron stars.

Through extensive model calculations, physicists at Goethe University Frankfurt have reached general conclusions about the internal structure of neutron stars, where matter reaches enormous densities: depending on their mass, the stars can have a core that is either very stiff or very soft. The findings were published simultaneously in two articles.

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Neutron stars are extremely compact objects that can form after the death of a star. They have the mass of our sun or even more, but are incredibly compressed into a sphere with the diameter of a large city. Since their discovery more than 60 years ago, scientists have been trying to decipher their structure. Thus far, however, little is known about the interior of neutron stars. 

As their extreme properties prevent them from being recreated on Earth in the laboratory, the greatest challenge is to simulate the extreme conditions inside neutron stars. There are therefore many models in which various properties – from density and temperature – are described with the help of so-called equations of state. These equations attempt to describe the structure of neutron stars from the stellar surface to the inner core.

Now physicists at Goethe University Frankfurt have succeeded in adding further crucial pieces to the puzzle. The working group led by Prof. Luciano Rezzolla at the Institute of Theoretical Physics developed more than a million different equations of state that satisfy the constraints set by data obtained from theoretical nuclear physics on the one hand, and by astronomical observations on the other.

When evaluating the equations of state, the working group made a surprising discovery: “Light” neutron stars (with masses smaller than about 1.7 solar masses) seem to have a soft mantle and a stiff core, whereas “heavy” neutron stars (with masses larger than 1.7 solar masses) instead have a stiff mantle and a soft core.

“This result is very interesting because it gives us a direct measure of how compressible the center of neutron stars can be,” says Prof. Luciano Rezzolla, “Neutron stars apparently behave a bit like chocolate pralines: light stars resemble those chocolates that have a hazelnut in their center surrounded by soft chocolate, whereas heavy stars can be considered more like those chocolates where a hard layer contains a soft filling.”

Crucial to this insight was the speed of sound, a study focus of Bachelor’s student Sinan Altiparmak. This quantity measure describes how fast sound waves propagate within an object and depends on how stiff or soft matter is. Here on Earth, the speed of sound is used to explore the interior of the planet and discover oil deposits.

By modeling the equations of state, the physicists were also able to uncover other previously unexplained properties of neutron stars. For example, regardless of their mass, they very probably have a radius of only 12 km. Thus, they are just as large in diameter as Goethe University’s hometown Frankfurt.

Author Dr. Christian Ecker explains: “Our extensive numerical study not only allows us to make predictions for the radii and maximum masses of neutron stars, but also to set new limits on their deformability in binary systems, that is, how strongly they distort each other through their gravitational fields. These insights will become particularly important to pinpoint the unknown equation of state with future astronomical observations and detections of <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

gravitational waves
Gravitational waves are distortions or ripples in the fabric of space and time. They were first detected in 2015 by the Advanced LIGO detectors and are produced by catastrophic events such as colliding black holes, supernovae, or merging neutron stars.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>gravitational waves from merging stars.”

So, while the exact structure and composition of matter inside neutron stars continue to remain a mystery, the wait until its discovery can certainly be sweetened with a chocolate or two.

References:

“On the Sound Speed in Neutron Stars” by Sinan Altiparmak, Christian Ecker and Luciano Rezzolla, 10 November 2022, The Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ac9b2a

“A General, Scale-independent Description of the Sound Speed in Neutron Stars” by Christian Ecker and Luciano Rezzolla, 10 November 2022, The Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ac8674

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Nature’s Ultra-Rare Isotopes Can’t Hide from this New Particle Accelerator

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A new particle accelerator at Michigan State University is producing long-awaited results. It’s called the Facility for Rare Isotope Beams, and it was completed in January 2022. Researchers have published the first results from the linear accelerator in the journal Physics Review Letters.

 

Physicists sometimes describe isotopes as different flavours of the same element. An atom of any element always has the same number of protons in its nucleus, but the number of neutrons can vary. Atoms of the same element with different numbers of neutrons are called isotopes. Carbon, for example, always has 6 protons, and its atomic number is 6. But there are different isotopes of carbon, each with a different number of neutrons, varying from 2 to 16.

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There are only two long-lived and stable isotopes of carbon: carbon-12 (12C) and carbon-13 (13C). Neither one decays, while all other carbon isotopes do. Some carbon isotopes last only a few thousand years; others exist for only the briefest moments. It’s the same with isotopes of other elements. And whether an isotope lasts for trillions of years or a trillionth of a second, its existence plays a role in nature.

Isotopes are essential in understanding many things in nature, including astrophysical objects like neutron stars and the nature and history of our Solar System. Scientists compare isotope ratios in different objects to see how they might be related. Scientists sometimes call the different ratios “fingerprints” because they fulfill a similar evidentiary role. For example, scientists measured the isotope fingerprints of Earth and compared them to Apollo lunar samples to understand how the Moon formed.

Physicists have been studying and identifying isotopes for over a century. With the advent of more powerful particle accelerators, researchers have identified isotopes that exist only for nanoseconds. It takes extremely high energy levels to produce these elusive atoms and sophisticated detectors to measure them. This is where the Facility for Rare Isotope Beams (FRIB) comes into play.

The Facility for Rare Isotope Beams is a linear accelerator shaped like a paper clip. The powerful accelerator propels atoms to speeds greater than 50% of the speed of light. Image Credit: FRIB/MSU.

Only about 250 isotopes of all types of atoms exist naturally on Earth. But theory predicts the existence of 7,000 of them, and researchers have already found about 3,000. FRIB is designed to close the gap between those numbers. Calculations predict that the accelerator will find 80% of all theorized isotopes. When its work is completed, the Chart of the Nuclides will list about 6,000 isotopes.

FRIB is made of three segments totalling 488 meters (1600 feet long), folded into a paper-clip shape. In the first stage, stable atoms of selected elements pass through a gas of electrons. The gas strips electrons from the atoms, leaving positively charged ions.

FRIB accelerates stable atoms through a gas of electrons that strip the electrons from the atom, leaving a positive ion. Image Credit: FRIB/MSU.
FRIB sends stable atoms through a gas of electrons that strips electrons from the atoms, leaving positive ions. Image Credit: FRIB/MSU.

Then FRIB accelerates the positive ions to about half of the speed of light before directing them into their target. As the stream of ions strikes the target, the collision makes the ions lose or gain protons and neutrons. That makes them unstable, producing thousands of rare isotopes, some of which last for only brief moments.

Before they can decay, the isotopes pass through a series of magnets acting as separators. They filter out isotopes by momentum and electrical charge. What remains are the isotopes desired for a particular experiment, which reach FRIB’s suite of instruments that measure the nature of the particles.

After colliding with the target, the rare and unstable isotopes pass through a series of magnets that filter out unwanted isotopes. Image Credit: FRIB/MSU.
After colliding with the target, the rare and unstable isotopes pass through a series of magnets that filter out unwanted isotopes. Image Credit: FRIB/MSU.

Researchers can’t direct FRIB to produce specific isotopes. It’s all based on probabilities. Scientists say that creating the rarest of isotopes in FRIB faces long odds: 1 in 1 quadrillion. But FRIB produces so many collisions and isotopes in a single run that 1 in 1 quadrillion isn’t insurmountable. The mass production of collisions and isotopes led to the prediction that the accelerator could produce 80% of all theorized isotopes.

FRIB has already run two experiments. The first was run at only 25% of the accelerator’s full power. It created a beam of Calcium-48 and directed it into a beryllium target. This resulted in about 40 different isotopes reaching the detectors. By measuring the time of arrival, what isotope it was, and how long it took to decay, the experiment detected five new half-lives for exotic isotopes of phosphorus, silicon, aluminum, and magnesium. Measuring these half-lives provides insights into different models of the atomic realm.

Researchers from multiple institutions took part in the first experiment. The lead spokesperson for the first experiment is Heather Crawford, a physicist at Berkeley Lab. A new paper in the Physical Review Letters presented the results.

“This is a basic science question, but it links to the bigger picture for the field. Our aim is to describe not only these nuclei, but all kinds of nuclei. These models help us fill in the gaps, which helps us more reliably predict things we haven’t been able to measure yet.”

Heather Crawford, Berkeley Lab staff scientist, Nuclear Science Division

The second experiment was directed at understanding neutron stars. Neutron stars are stellar remnants, the collapsed cores of stars that exploded as supernovae. Neutron stars are made of extraordinarily dense matter and no longer undergo fusion. There’s still a lot going on in neutron stars, and there’s much theorizing about how they function. Scientists know that neutron stars contain rare isotopes of scandium, calcium and potassium.

In this experiment, researchers produced a beam of selenium-28 to produce the same rare scandium, calcium, and potassium isotopes. This experiment began in June, and the results haven’t been published yet. But it shows how FRIB can address fundamental questions about some of nature’s most extreme objects.

FRIB can address other questions, not all related to astrophysical objects. Some of its research should shed light on more practical concerns.

In the past, research into nuclear science has produced results that have reduced suffering and shaped people’s lives. Medical imaging technologies like Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) are the results of basic research into nuclear physics. So are smoke detectors, something so simple, effective, and inexpensive they can easily be taken for granted. It’s impossible to calculate how many lives smoke detectors have saved and how much tragedy they’ve prevented. Same with MRI and PET.

Scientists are hopeful that research at FRIB can make similarly valuable contributions to society. History shows us that we can’t always predict the practical benefits of basic research like this but that civilization would look very different without it.

When American physicist Isidor Isaac Rabi developed a way to measure sodium atoms’ movement and magnetic properties, he wasn’t thinking about imaging the insides of human bodies. But as his work and the work of other scientists continued, scientists understood that they could use these measurements and other advances to eventually detect cancer. This work led to the development of MRI, a commonplace medical technology in our world. (Rabi eventually won the Nobel Prize in Physics for his discovery of nuclear magnetic resonance.)

Is it too much to hope that FRIB can somehow contribute to medical science? Not at all, though there are no specifics right now. But the history of one type of cancer treatment is another case study of how research into nuclear physics has reduced suffering. It’s called proton beam therapy.

Proton beam therapy allows for higher doses of radiation to be given to children and sensitive tissues like livers, eyes, and optic nerves. It can target cancer cells more precisely and avoid damaging healthy cells.

It stems directly from research at the Harvard Cyclotron Laboratory in the 1940s. In fact, the first proton beam therapy was given to patients with particle accelerators built for research, not medicine. Now proton beams are regularly used to remove eye tumours, among other things.

Will FRIP eventually treat patients? No. That’s highly unlikely.

But history shows that if we want to make advances that reduce suffering, facilities like FRIP can play a significant role.

FRIP was built to learn about some of nature’s most fascinating objects, like neutron stars. Our understanding of physics is incomplete, and researchers at FRIP intend to fill in some of the blanks. The rest of us get to come along for the ride, and that’s a win for intellectually curious people everywhere.

And if some of what we learn is applied to our everyday lives, that’s a win, too.

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