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Why some scientists want to rebrand shark attacks as 'negative encounters' – CBC.ca

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Dropping the phrase “shark attack” is a great way to change the narrative about the much-maligned sea creatures, says marine scientist Toby Daly-Engel.

Last week, the Sydney Morning Herald reported that scientists in two Australian states are moving away from that term in favour of more neutral language, like “bites,” “incidents” or “negative encounters.”

The story drew swift mockery online, as well as backlash from an organization that represents people who have been injured by sharks

But Daly-Engel, director of the Florida Tech Shark Conservation Lab, says we’re long overdue for a language shift when it comes to the misunderstood ocean dwellers, which are at a greater risk from humans than vice versa.

Here is part of her conversation with As It Happens guest host Susan Bonner. 

What do you make of the Australian decision to rebrand shark attacks?

I think it’s a really good step in the right direction, because for a long time we’ve known that [with] shark attacks, it really depends on people, not on sharks. And so trying to rebrand these interactions in a way that more accurately represents the event is really good as far as we’re concerned.

But this is being mocked quite a bit, especially the suggested terminology, “negative” shark “encounters.” Isn’t a shark attack sometimes just a shark attack?

Actually, most shark attacks are what we call provoked, meaning they are instigated by humans. And so the notion of a shark attack kind of conjures an attack out of the blue by some sort of mindless, bloodthirsty predator. And in reality, that’s not it at all.

Most things that get labelled by the media as shark attack are things like people poking sharks underwater, chumming where people are swimming or doing other things that really create a situation where somebody might be hurt by a shark. 

But the vast majority of these interactions are not actually due to the shark. And so the notion of shark attack, even though it’s the most recognizable terminology, it’s really inaccurate.

I guess, though, if a shark is biting you, whether it’s being called an attack or an interaction isn’t really the first thing on your mind.

Sure. But at the same time, in general, sharks have, in reality, way more to fear from humans than we do from them. 

Shark attack[s are] monumentally rare, more rare than being bitten by someone from New York, statistically speaking. Whereas humans are — conservatively, this is an underestimate — we’re taking at least 100 million sharks out of the ocean every year.

And what we’re finding as scientists is that [sharks] … reproduce more slowly than we realized, even more slowly than people. And so many, many shark populations are really in trouble. And that’s not good because sharks as predators are really helpful for keeping the rest of the food items, the prey in the food web, in check and keeping them in balance.

The terminology may sound unnatural or silly to some people, but that’s because most people’s concept of what is a shark attack is really based on the rarest kind.– Toby Daly-Engel, marine scientist 

What kind of a difference do you believe this change of terminology could mean for how people view sharks?

I hope that it sheds light on the fact that sharks have more to fear from us than we do from them.

Like I said, the terminology may sound unnatural or silly to some people, but that’s because most people’s concept of what is a shark attack is really based on the rarest kind. 

Sharks are much more careful, much more fragile than people realize. They’re very long lived. Some species we now know can live over 400 years. They’re more likely to scavenge dead prey than they are to attack live prey, because their natural prey has things like spines and claws and beaks that can hurt them.

So when an attack occurs on a human, it’s because we are in their environment and they mistake us for a natural prey item, or they don’t know what we are and they go to figure it out with. Like dogs and babies, sharks can only really figure things out using their mouths.

A woman floating on the surface of the water in Compass Cay in the Exumas, as nurse sharks swim beneath her. Scientists say that despite pop culture depictions, most sharks are small to medium-sized. (Khaichuin Sim/Getty Images)

A spokesperson for a group representing people who have been bitten by sharks told the [Sydney Morning Herald] that he’s worried about “sanitizing” shark bites. What would you say to him?

I would say that shark attacks in general are going down per capita, even though the number of people that are in the water is going up. And that’s because we know we’ve lost up to 70 per cent of all sharks just in the last 50 years. And that is going to have grave consequences on our ocean health.

Anybody who likes the ocean, likes seeing fish in the ocean, all of that diversity is in danger without the predators. And most sharks are not at the top of the food chain. Most sharks are not what we think of as apex predators. There’s not that many massive ones. Most sharks are these cute little medium-sized things. They are both predator and prey. And without them, what we see is what’s called extinction cascade.

Considering you’re more likely to get struck by lightning … than bitten by a shark, considering you’re more likely to be killed by a vending machine than a shark, I think that there is very little chance of this type of measure minimizing shark attack. It has a much better chance of kind of helping people to understand that most of what the media calls shark attacks are really not the shark’s fault. They’re really just due to people.

Maybe we need some horror movies about vending machine attacks and New York City bite attacks.

I mean, just don’t shake them. Like, if you can’t get your chips out, just leave them there. That’s all I can say.

But after movies like Jaws and the innate fear that people have about sharks, is rebranding really going to make much of a difference here?

Even if there’s some mockery, there’s some silliness, regardless of this kind of attention, if it can help people understand the role that sharks play in the ecosystem and how mistaken our ideas are about shark attack, then, yeah, maybe it’ll do a little bit of good.

Sharks are feared. There are very few laws protecting them. And yet we know that these things grow more slowly and reproduce more slowly than just about any animal on Earth. And so they are incredibly in need of protection.

So every little bit can help because there’s not a lot of, you know, big movements out there for shark advocacy. There’s no such thing as shark-safe tuna, for instance. So I think because there is that fear, it’s even more important that institutions speak up on behalf of these animals, which are really, really important to the health of our planet’s oceans. 


Written by Sheena Goodyear. Interview produced by Chris Harbord. Q&A has been edited by length and clarity.

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Astronomers Discover an Intermediate-Mass Black Hole as it Destroys a Star – Universe Today

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Supermassive black holes (SMBH) reside in the center of galaxies like the Milky Way. They are mind-bogglingly massive, ranging from 1 million to 10 billion solar masses. Their smaller brethren, intermediate-mass black holes (IMBH), ranging between 100 and 100,000 solar masses, are harder to find.

Astronomers have spotted an intermediate-mass black hole destroying a star that got too close. They’ve learned a lot from their observations and hope to find even more of these black holes. Observing more of them may lead to understanding how SMBHs got so massive.

When a star gets too close to a powerful black hole, a tidal disruption event (TDE) occurs. The star is torn apart and its constituent matter is drawn to the black hole, where it gets caught in the hole’s accretion disk. The event releases an enormous amount of energy, outshining all the stars in the galaxy for months, even years.

That’s what happened with TDE 3XMM J215022.4-055108, which is more readily known as TDE J2150. Astronomers were only able to spot the elusive IMBH because of the burst of x-rays emitted by the hot gas from the star as it was torn apart. J2150 is about 740 million light-years from Earth in the direction of the Aquarius constellation. Now a team of researchers has used observations of the distant J2150 and existing scientific models to learn more about the IMBH.

They’ve published their results in a paper titled “Mass, Spin, and Ultralight Boson Constraints from the Intermediate Mass Black Hole in the Tidal Disruption Event 3XMM J215022.4?055108.” The lead author is Sixiang Wen from the University of Arizona. The paper is published in The Astrophysical Journal.

“The fact that we were able to catch this invisible black hole while it was devouring a star offers a remarkable opportunity to observe what otherwise would be invisible.”

Ann Zabludoff, co-author University of Arizona.

IMBHs are elusive and difficult to study. Astronomers have found several of them in the Milky Way and in nearby galaxies. Mostly they’ve been spotted because of their low-luminosity active galactic nuclei. In 2019 the LIGO and Virgo gravitational wave observatories spotted a gravitational wave from the merger of two IMBHs. As it stands now, there’s a catalogue of only 305 IMBH candidates, even though scientists think they could be common in galactic centers.

One of the problems in seeing them is their low mass itself. While SMBHs can be found by observing how their mass affects the stellar dynamics of nearby stars, IMBHs are typically too small to do the same. Their gravity isn’t powerful enough to change the orbits of nearby stars.

“The fact that we were able to catch this black hole while it was devouring a star offers a remarkable opportunity to observe what otherwise would be invisible,” said Ann Zabludoff, UArizona professor of astronomy and co-author on the paper. “Not only that, by analyzing the flare we were able to better understand this elusive category of black holes, which may well account for the majority of black holes in the centers of galaxies.”

This is a Hubble image of J2150 in the white circle. It’s situated inside a dense cluster of stars about 740 million light-years away. X-ray emissions from the TDE were used to spot the IMBH, but Hubble’s visible-light capabilities were needed to pinpoint its location. Image Credit: NASA, ESA, and D. Lin (University of New Hampshire)

It was the eruption of x-rays that made the event visible. The team compared the observed x-rays with models and was able to confirm the presence of an IMBH. “The X-ray emissions from the inner disk formed by the debris of the dead star made it possible for us to infer the mass and spin of this black hole and classify it as an intermediate black hole,” lead author Wen said.

This is the first time that observations have been detailed enough to be able to use a TDE flare to confirm the presence of an IMBH. It’s a big deal, because though we know that SMBHs lie in the center of galaxies like the Milky Way and larger, our understanding of smaller galaxies and their IMBHs is much more limited. They’re just really hard to see.

“We still know very little about the existence of black holes in the centers of galaxies smaller than the Milky Way,” said co-author Peter Jonker of Radboud University and SRON Netherlands Institute for Space Research, both in the Netherlands. “Due to observational limitations, it is challenging to discover central black holes much smaller than 1 million solar masses.”

The mystery surrounding IMBHs feeds into the mystery surrounding SMBHs. We can see SMBHs at the heart of large galaxies, but we don’t know exactly how they got that massive. Did they go through mergers? Maybe. Through the accretion of matter? Maybe. Astrophysicists mostly agree that both mechanisms may play a role.

Another question surrounds SMBH “seeds.” The seeds could be IMBHs of tens or hundreds of solar masses. The IMBHs themselves could’ve grown from stellar-mass black holes that grew into IMBHs through the accretion of matter. Another possibility is that long before there were actual stars, there were large gas clouds that collapsed into quasi-stars, that then collapsed into black holes. These strange entities would collapse directly from quasi-star to black hole without ever becoming a star, and are known as direct collapse black holes. But these are all hypotheses and models. Astrophysicists need more actual observations, like in the case of TDE J2150, to confirm or rule anything out.

“Therefore, if we get a better handle of how many bona fide intermediate black holes are out there, it can help determine which theories of supermassive black hole formation are correct,” Jonker said.

This artist's illustration depicts what astronomers call a "tidal disruption event," or TDE, when an object such as a star wanders too close to a black hole and is destroyed by tidal forces generated from the black hole's intense gravitational forces. (Credit: NASA/CXC/M.Weiss.
This artist’s illustration depicts what astronomers call a “tidal disruption event,” or TDE, when an object such as a star wanders too close to a black hole and is destroyed by tidal forces generated from the black hole’s intense gravitational forces. (Credit: NASA/CXC/M.Weiss.

The team of researchers was also able to measure the black hole’s spin, which has implications for black hole growth, and maybe for particle physics, too. The black hole is spinning quickly, but it’s not spinning as fast as possible. It begs the question, how did the IMBH attain a speed in this range? The spin opens up some possibilities and eliminates others.

“It’s possible that the black hole formed that way and hasn’t changed much since, or that two intermediate-mass black holes merged recently to form this one,” Zabludoff said. “We do know that the spin we measured excludes scenarios where the black hole grows over a long time from steadily eating gas or from many quick gas snacks that arrive from random directions.”

The spin rate may shed some light on potential particle candidates for dark matter, too. One of the hypotheses says that dark matter is made up of particles never seen in a laboratory, called ultralight bosons. These exotic particles, if they exist, would have less than one-billionth the mass of an electron. The IMBHs spin rate may preclude the existence of these candidate particles.

“If those particles exist and have masses in a certain range, they will prevent an intermediate-mass black hole from having a fast spin,” co-author Nicholas Stone said. “Yet J2150’s black hole is spinning fast. So, our spin measurement rules out a broad class of ultralight boson theories, showcasing the value of black holes as extraterrestrial laboratories for particle physics.”

[embedded content]

This discovery will build toward a better understanding of dwarf galaxies and their black holes, too. But for that to happen, astrophysicists need to observe more of these IMBH tidal disruption events.

“If it turns out that most dwarf galaxies contain intermediate-mass black holes, then they will dominate the rate of stellar tidal disruption,” Stone said. “By fitting the X-ray emission from these flares to theoretical models, we can conduct a census of the intermediate-mass black hole population in the universe,” Wen added.

As is often the case in astronomy, astrophysics, and cosmology, future telescopes and observatories should advance our knowledge considerably. In this, the Vera C. Rubin Observatory could play a role. The Rubin could discover thousands of TDEs each year.

Then we may finally be able to piece together the story of not only IMBHs but also SMBHs.

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NASA splits human spaceflight unit in two, reflecting new orbital economy – CTV News

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NASA is splitting its human spaceflight department into two separate bodies – one centred on big, future-oriented missions to the moon and Mars, the other on the International Space Station and other operations closer to Earth.

The reorganization, announced by NASA chief Bill Nelson on Tuesday, reflects an evolving relationship between private companies, such as SpaceX, that have increasingly commercialized rocket travel and the federal agency that had exercised a U.S. monopoly over spaceflight for decades.

Nelson said the shake-up was also spurred by a recent proliferation of flights and commercial investment in low-Earth orbit even as NASA steps up its development of deep-space aspirations.

“Today is more than organizational change,” Nelson said at a press briefing. “It’s setting the stage for the next 20 years, it’s defining NASA’s future in a growing space economy.”

The move breaks up NASA’s Human Exploration and Operations Mission Directorate, currently headed by Kathy Leuders, into two separate branches.

Leuders will keep her associate administrator title as head of the new Exploration Systems Development Mission Directorate, focusing on NASA’s most ambitious, long-term programs, such as plans to return astronauts to the moon under project Artemis, and eventual human exploration of Mars.

A retired deputy associate administrator, James Free, who played key roles in NASA’s space station and commercial crew and cargo programs, will return to the agency as head of the new Space Operations Mission Directorate.

His branch will primarily oversee more routine launch and spaceflight activities, including missions involving the space station and privatization of low-Earth orbit, as well as sustaining lunar operations once those have been established.

“This approach with two areas focused on human spaceflight allows one mission directorate to operate in space while the other builds future space systems,” NASA said in a press release announcing the move.

The announcement came less than a week after SpaceX, which had already flown numerous astronaut missions and cargo payloads to the space station for NASA, launched the first all-civilian crew ever to reach orbit and returned them safely to Earth.

(Reporting by Steve Gorman in Los Angeles; Editing by Leslie Adler)

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Elon Musk trolls Biden with Trump line over perceived Inspiration4 snub – CNET

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SpaceX CEO Elon Musk unveiled the Dragon V2 in May 2014.


Tim Stevens/CNET

Elon Musk, SpaceX founder and leading orbital travel agent, was feeling a bit slighted by the world’s most powerful man  after President Joe Biden failed to acknowledge the company’s landmark Inspiration4 mission that sent four civilians on a three-day trip in orbit of our planet. 

The flight was bankrolled by billionaire Jared Isaacman, who commanded the mission aboard a Crew Dragon capsule, alongside geologist Sian Proctor, data engineer Chris Sembroski and St. Jude Children’s Research Hospital employee Hayley Arceneaux. The quartet splashed down safely off the coast of Florida on Saturday.

The mission served as a fundraiser for St. Jude, with over $60 million raised from the public so far. Isaacman also pledged $100 million and Musk added $50 million.

When a Twitter user asked why the president hadn’t acknowledged Inspiration4, Musk hopped into the replies.

“He’s still sleeping,” the CEO wrote, in an apparent reference to Donald Trump’s favorite nickname for his former adversary, “sleepy” Joe Biden.

It seems fair to point out, as a number of other Twitter users have, that the president may have a few other things on his plate at the moment, like continuing to manage the response to a global pandemic, climate crisis and various national security threats. 

For what it’s worth, NASA administrator Bill Nelson, a Biden appointee, did offer his congratulations to the crew multiple times.

The White House did not immediately respond to a request for comment.

Inspiration4 is the latest in a string of pioneering space tourism missions this year. Richard Branson flew to the edge of space on the first fully crewed flight of his Virgin Galactic spaceplane in July. Nine days later, Amazon and Blue Origin founder Jeff Bezos cruised a bit higher with three other passengers on his New Shepard spacecraft. 

Unlike those flights, which lasted under 15 minutes each, the Inspiration4 mission was a much more complex venture that saw the four passengers performing scientific research during the multiple day flight as they orbited Earth over 40 times. 

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