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Scientists receive US$15 million to resurrect woolly mammoth – CTV News

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Bringing extinct creatures back to life is the lifeblood of science fiction. At its most tantalizing, think Jurassic Park and its stable of dinosaurs.

Advances in genetics, however, are making resurrecting lost animals a tangible prospect. Scientists have already cloned endangered animals and can sequence DNA extracted from the bones and carcasses of long-dead, extinct animals.

Geneticists, led by Harvard Medical School’s George Church, aim to bring the woolly mammoth, which disappeared 4,000 years ago, back to life, imagining a future where the tusked ice age giant is restored to its natural habitat.

The efforts got a major boost on Monday with the announcement of a US$15 million investment.

Proponents say bringing back the mammoth in an altered form could help restore the fragile Arctic tundra ecosystem, combat the climate crisis, and preserve the endangered Asian elephant, to whom the woolly mammoth is most closely related. However, it’s a bold plan fraught with ethical issues.

The goal isn’t to clone a mammoth — the DNA that scientists have managed to extract from woolly mammoth remains frozen in permafrost is far too fragmented and degraded — but to create, through genetic engineering, a living, walking elephant-mammoth hybrid that would be visually indistinguishable from its extinct forerunner.

“Our goal is to have our first calves in the next four to six years,” said tech entrepreneur Ben Lamm, who with Church has cofounded Colossal, a bioscience and genetics company to back the project.

‘NOW WE CAN ACTUALLY DO IT’

The new investment and focus brought by Lamm and his investors marks a major step forward, said Church, the Robert Winthrop Professor of Genetics at Harvard Medical School.

“Up until 2021, it has been kind of a backburner project, frankly. … but now we can actually do it,” Church said.

“This is going to change everything.”

Church has been at the cutting edge of genomics, including the use of CRISPR, the revolutionary gene editing tool that has been described as rewriting the code of life, to alter the characteristics of living species. His work creating pigs whose organs are compatible with the human body means a kidney for a patient in desperate need of a transplant might one day come from a swine.

“We had to make a lot of (genetic) changes, 42 so far to make them human compatible. And in that case we have very healthy pigs that are breeding and donating organs for preclinical trials at Massachusetts General Hospital,” he said.

“With the elephant, it’s a different goal but it’s a similar number of changes.”

The research team has analyzed the genomes of 23 living elephant species and extinct mammoths, Church said. The scientists believe they will need to simultaneously program “upward of 50 changes” to the genetic code of the Asian elephant to give it the traits necessary to survive and thrive in the Arctic.

These traits, Church said, include a 10-centimeter layer of insulating fat, five different kinds of shaggy hair including some that is up to a meter long, and smaller ears that will help the hybrid tolerate the cold. The team also plans to try to engineer the animal to not have any tusks so they won’t be a target for ivory poachers.

Once a cell with these and other traits has successfully been programmed, Church plans to use an artificial womb to make the step from embryo to baby — something that takes 22 months for living elephants. However, this technology is far from nailed down, and Church said they hadn’t ruled out using live elephants as surrogates.

“The editing, I think, is going to go smoothly. We’ve got a lot of experience with that, I think, making the artificial wombs is not guaranteed. It’s one of the few things that is not pure engineering, there’s maybe a tiny bit of science in there as well, which always increases uncertainty and delivery time,” he said.

SKEPTICISM

Love Dalén, professor of evolutionary genetics at the Centre for Palaeogenetics in Stockholm who works on mammoth evolution, believes there is scientific value in the work being undertaken by Church and his team, particularly when it comes to conservation of endangered species that have genetic diseases or a lack of genetic variation as result of inbreeding.

“If endangered species have lost genes that are important to them … the ability to put them back in the endangered species, that might prove really important,” said Dalén, who is not involved in the project.

“I still wonder what the bigger point would be. First of all, you’re not going to get a mammoth. It’s a hairy elephant with some fat deposits.

“We, of course, have very little clue about what genes make a mammoth a mammoth. We know a little, bit but we certainly don’t know anywhere near enough.”

Others say it’s unethical to use living elephants as surrogates to give birth to a genetically engineered animal. Dalén described mammoths and Asian elephants as being as different as humans and chimpanzees.

“Let’s say it works, and there’s no horrible consequences. No surrogate elephant moms die,” said Tori Herridge, an evolutionary biologist and mammoth specialist at the Natural History Museum in London, who is not involved in the project.

“The idea that by bringing mammoths back and by placing them into the Arctic, you engineer the Arctic to become a better place for carbon storage. That aspect I have number of issues with.”

Some believe large that, before their extinction, grazing animals like mammoths, horses and bison maintained the grasslands in our planet’s northern reaches and kept the earth frozen underneath by tramping down the grass, knocking down trees and compacting snow. Reintroducing mammoths and other large mammals to these places will help revitalize these environments and slow down permafrost thaw and the release of carbon.

However, both Dalén and Herridige said there was no evidence to back up this hypothesis, and it was hard to imagine herds of cold-adapted elephants making any impact on an environment that’s grappling with wild fires, riddled with mires and warming faster than anywhere else in the world.

“There’s absolutely nothing that says that putting mammoths out there will have any, any effect on climate change whatsoever,” Dalén said.

Ultimately, the stated end goal of herds of roaming mammoths as ecosystem engineers may not matter, and neither Herridge nor Dalén knock Church and Lamm for embarking on the project. Many people might be happy to pay to get up close to a proxy mammoth.

“Maybe it’s fun to showcase them in the zoo. I don’t have a big problem with that if they want to put them in a park somewhere and, you know, make kids more interested in the past,” Dalén said.

There is “zero pressure” for the project to make money, Lamm said. He is banking on the endeavor resulting in innovations that have applications in biotechnology and health care. He compared it to how the Apollo project got people caring about space exploration but also resulted in a lot of incredible technology, including GPS.

“I am absolutely fascinated by this. I’m drawn to people who are technologically adventurous and it is possible it will make a positive difference,” Herridge, the mammoth expert, said.

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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.”

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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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