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Exploding Stars May Have Killed Off Prehistoric Predators

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Even though Earth is floating in the void, it does not exist in a vacuum. The planet is constantly bombarded by stuff from space, including a daily deluge of micrometeorites and a shower of radiation from the sun and more-distant stars. Sometimes, things from space can maim or kill us, like the gargantuan asteroid that wiped out the dinosaurs. More often, stellar smithereens make their way to Earth and the moon and then peacefully settle, remaining for eternity, or at least until scientists dig them up.

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Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

Dark matter, if it exists, is probably in the latter category. If hypothetical weakly interacting massive particles (WIMPs) are real, their collisions with regular matter may have left fossil traces in the depths of the planet’s rock record. A team of physicists has proposed a new way to look for such fossil tracks as a way of hunting for dark matter, as I reported earlier this month.

But the search for cosmic debris on Earth has a long history. Other researchers have demonstrated that it’s possible to find fossil evidence of astrophysical particles in Earth’s crust. Some researchers are pondering how these cosmic events affect Earth — even whether they have altered the course of evolution. A new study suggests that energetic particles from an exploding star may have contributed to the extinction of a number of megafauna, including the prehistoric monster shark megalodon, which went extinct at around the same time.

“It’s an interesting coincidence,” said Adrian Melott, an astrophysicist at the University of Kansas and the author of a new paper.

When a star dies, its guts stream out into the cosmos. Among those stellar remains are isotopes, or variants, of elements like iron. One such isotope, iron-60, is rare on Earth but abundant in supernovas. In 2016 and 2017, astrophysicists traced iron-60 found on Earth’s seafloor and on the moon back to two ancient supernovasin Earth’s galactic neighborhood. One event took place roughly 2.6 million years ago, and another sometime between 6.5 million and 8.7 million years ago, researchers say.

“A lot of things would not leave a definite residue,” Melott said in an interview, but iron-60 does. “That is smoking-gun evidence of something happening.”

Given such a smoking gun, Melott turned to a question scientists have pondered since at least the 1950s: How might these supernovas affect Earth and its life? In the new paper, he describes how a supernova would produce a shower of subatomic particles called muons that could damage DNA, leading to widespread mutations in organisms, and even the extinction of species.

Muons are sort of like extra-heavy electrons. They can sail through Earth’s atmosphere with greater ease than protons and electrons. “They get to the ground, they hit you, and some of them will interact with you, and damage your DNA, Melott said. “They are in a sweet spot for affecting ground-based life.”

Melott hypothesized that a supernova around 2.6 million years ago would have increased the flow of muons streaming through the atmosphere several hundred times over. He and his coauthors estimated that cancer rates could have increased by 50 percent for an animal the size of a human. For a mammoth or a megalodon — which was the size of a school bus — the radiation dose would be even worse, Melott said.

The idea that supernovas might affect life on Earth is not completely new. The paleontologist Otto Schindewolf proposed in the 1950s that supernovas might have induced mutations in large animals. But his theory did not catch on. In 1968, the astronomers K.D. Terry and W.H. Tucker suggested that mass extinctions might have been caused by nearby exploding stars, and the hypothesis has been reanimated several times since.

Yet most theories blame the die-offs on widespread climate changes, not on direct mutations. Supernova explosions could obliterate Earth’s ozone layer, for instance, which would wreak havoc on marine plankton and coral reefs. Supernovas could also generate an excess of cosmic rays that could seed cloud formation, leading to a “cosmic-ray winter,” Henrik Svensmark of the Technical University of Denmark wrote in an email.

Svensmark’s work shows that Earth’s geological record coincides in some cases with the expected flux of supernova-related cosmic rays. And a 1995 paper by the physicists John Ellis and David Schramm concluded that catastrophic supernovas could be expected every few hundred million years, in keeping with the pace of mass extinctions.

As for Melott’s hypothesis that the single supernova 2.6 million years ago led directly to extinctions, he points to a few lines of evidence. At the Pliocene-Pleistocene boundary 2.6 million years ago, some 36 percent of marine genera went extinct, mostly in coastal waters. Larger animals would catch a higher muon dose in those regions, Melott points out.

But unlike those of iron-60 and WIMPs, the mark of muons would not remain in the fossil record, making the direct connection between muons and extinctions all but impossible to prove. “These muons would really not leave any trace,” Melott said.

Even if muon showers and iron-60 from dying stars cannot be directly linked to extinctions, their presence demonstrates a profound truth: Earth, and everything on it, is a part of the universe, not apart from it. The stars may indeed hold some answers to our fates.

Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.


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Riot police squads intervene as pro-Israel and pro-Palestinian protesters clash in Montreal

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People wave flags atop cars in traffic during a demonstration to voice support for the people of Palestine, at Toronto City Hall in Toronto, Ontario, Canada, on 15 May 2021.


People wave flags atop cars in traffic during a demonstration to voice support for the people of Palestine, at Toronto City Hall in Toronto, Ontario, Canada, on 15 May 2021.

  • Violence
    between pro-Israel and pro-Palestine protesters in Montreal was condemned by
    Canadian Prime Minister Justin Trudeau.
  • Montreal’s
    city police force intervened and declared the protests illegal after tensions
    heightened and clashes broke out.
  • Israeli
    strikes killed 42 Palestinians in the Gaza Strip on Sunday, the worst daily
    toll in almost a week of clashes.

Montreal
– Canadian Prime Minister Justin Trudeau on Sunday condemned the violence and
“despicable rhetoric” that marked several weekend protests throughout
the country, after clashes between pro-Israel and pro-Palestinian protesters in
Montreal.

The
worst violence in years, sparked by unrest in Jerusalem, is raging between the
Jewish state and Islamist militants.

Israeli
strikes killed 42 Palestinians in the Gaza Strip on Sunday, the worst daily
toll in almost a week of deadly clashes.

Speaking
after protests in Montreal, Trudeau condemned what he said was “despicable
rhetoric and violence we saw on display in some protests this weekend”.

While
insisting on the “right to assemble peacefully and express themselves
freely in Canada”, Trudeau stressed in a tweet that there was no tolerance
for “antisemitism, Islamophobia, or hate of any kind”.

Earlier
on Sunday, Montreal police used tear gas following clashes between pro-Israel
and pro-Palestinian protesters.

Several
hundred demonstrators, draped in Israeli flags, had gathered in a central
Montreal square to express solidarity with the Jewish state.

‘Protesting is a right’

Although
the protest started peacefully, tensions ratcheted up with the arrival of
pro-Palestinian demonstrators and clashes soon broke out.

The
SPVM, Montreal’s city police force, declared the protests illegal, and squads
of riot police intervened, using tear gas to separate and disperse the two
groups, according to an AFP journalist at the scene.

The
police spent much of the afternoon in pursuit of the pro-Palestinian
protesters, who spread out and regrouped in commercial streets in the city centre.

Following
the clashes, Montreal Mayor Valerie Plante said on Twitter that
“protesting is a right”, but that “intolerance, violence and
anti-Semitism have no place here”.

She said:

Montreal is a city of peace.

Several
thousand pro-Palestinian demonstrators had gathered on Saturday in central
Montreal to denounce what they said were Israeli repression and “war
crimes” in Gaza.

“Terrorist
Israel”, some protesters chanted, while others held up a banner that read,
“Stop the genocide of Palestinian children”.

Pro-Palestinian
protests happened the same day in multiple Canadian cities, including Toronto,
Ottawa and Vancouver.


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Peter Thiel Helps Fund an App That Tells You What to Do

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“How would you feel about being able to pay to control multiple aspects of another person’s life?” asks the BBC.

“A new app is offering you the chance to do just that.”

When writer Brandon Wong recently couldn’t decide what takeaway to order one evening, he asked his followers on social media app NewNew to choose for him. Those that wanted to get involved in the 24-year-old’s dinner dilemma paid $5 (£3.50) to vote in a poll, and the majority verdict was that he should go for Korean food, so that was what he bought…

NewNew is the brainchild of Los Angeles-based entrepreneur Courtne Smith. The app, which is still in its “beta” or pre-full release stage, describes itself as “a human stock market where you buy shares in the lives of real people, in order to control their decisions and watch the outcome”. For many of us that sounds a bit ominous, but the reality is actually far less alarming. It is aimed at what it calls “creators” — writers, painters, musicians, fashion designers, bloggers etc. It is designed as a way for them to connect far more closely with their fans or followers than on other social media services and, importantly, monetise that connection…

Whenever a vote is cast the creator gets the money minus NewNew’s undisclosed commission… In addition to voting, followers can also pay extra — from $20 — to ask a NewNew creator to do something of their choosing, such as naming a character in a book after them. But the creator can reject all of these “bids”, and if they do so then the follower doesn’t have to part with the money…

Co-founder and chief executive Ms Smith, a 33-year-old Canadian, has big plans for NewNew, and has some heavyweight backers. Investors include Peter Thiel, the billionaire co-founder of PayPal, and the first outside person to put money into Facebook. Others with a stake in the business include leading US tech investment fund Andreessen Horowitz, and Hollywood actor Will Smith (no relation to Courtne). Snapchat has also given technical support.

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Sandpapergate will haunt Australia cricket forever: ex-bowling coach

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Cameron Bancroft. (Photo by Brenton Geach - Gallo Images/Getty Images)


Cameron Bancroft. (Photo by Brenton Geach – Gallo Images/Getty Images)

The 2018 ball-tampering scandal will haunt Australian cricket forever, much like the infamous underarm delivery of 40 years ago, the team’s former bowling coach David Saker said on Monday.

Saker was responding to opening batsman Cameron Bancroft suggesting that Australia’s bowlers knew about the plan in Cape Town to alter the ball which earned him a nine-month ban and rocked the game.

Saker was Australia’s bowling coach when Bancroft was caught trying to rough up the ball with sandpaper during the third Test against South Africa.

While refusing to be drawn on who knew what, Saker said “the finger-pointing is going to go on and on and on”.

“It’s like the underarm, it’s never going to go away,” he told Fairfax Media, referring to a 1981 incident when Trevor Chappell bowled underarm to ensure New Zealand lost a one-day match at the Melbourne Cricket Ground.

The notorious delivery is still cited in New Zealand and in cricketing circles as a prime example of unsporting conduct.

However, the ball-tampering scandal – dubbed “sandpapergate” – had a greater impact on Australian cricket, with the then-captain Steve Smith and his deputy David Warner suspended for a year from all cricket and stripped of their leadership roles.

Darren Lehmann also quit as coach and all the top brass from Cricket Australia left after a scathing review blasted their “arrogant and controlling” win-at-all-costs culture.

No one else among the team or coaching staff was held to account but Bancroft’s remarks in an interview with The Guardian newspaper hinted that the team’s bowlers at least knew about the plan.

“Obviously what I did benefits bowlers and the awareness around that, probably, is self-explanatory,” he said.

Saker added: “There was a lot of people to blame. It could have been me to blame, it could have been someone else. It could have been stopped and it wasn’t, which is unfortunate.

“Cameron’s a very nice guy. He’s just doing it to get something off his chest … He’s not going to be the last.”

In response, Cricket Australia said that if anyone had new information, they would look into it.

Saker said he was not opposed to a fresh investigation but added “I just don’t know what they’re going to find out.”

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Mexico’s Andrea Meza crowned Miss Universe

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Miss Universe Andrea Meza


Miss Universe Andrea Meza

UPDATE:

MISS UNIVERSE 2020/2021 IS ANDREA MEZA FROM MEXICO:


UPDATE:

THE MISS UNIVERSE 2020/2021 TOP 5:

1. Mexico

2. India

3. Brazil

4. Dominican Republic

5. Peru


UPDATE:

HERE ARE THE MISS UNIVERSE 2020/2021 TOP 10 CONTESTANTS:

1. Jamaica 

2. Dominican Republic 

3. India

4. Peru 

5. Australia 

6. Puerto Rico

7. Thailand

8. Costa Rica

9. Mexico

10. Brazil


UPDATE:

MISS UNIVERSE TOP 21 IN SWIMWEAR:


UPDATE:

MISS UNIVERSE TOP 21: 

1. Columbia

2. Peru 

3. Australia 

4. France

5. Myanmar

6. Jamaica 

7. Mexico 

8. Dominican Republic 

9. USA

10. Indonesia 

11. Argentina 

12. India

13. Curaçao

14. Puerto Rico

15. Phillipines 

16. Brazil

17. Great Britain

18. Nicaragua

19. Thailand 

20. Costa Rica

21. Vietnam


 UPDATE:

MISS UNIVERSE SOUTH AFRICA NATASHA JOUBERT WALKS THE STAGE AT MISS UNIVERSE 2020/2021:


74 contestants will compete for the title of Miss Universe on 16 May in Hollywood, Florida. 

The Miss Universe pageant takes place on 16 May in the US (02:00 to 05:00 on 17 May SA time). The show will be broadcast live on 1 Magic (DStv Channel 103) with a repeat at 21:30. 

Reigning Miss Universe Zozibini Tunzi of South Africa will crown her successor at the end of the event.

Representing South Africa is Natasha Joubert, and South Africans are hoping for the “magic double” – back-to-back consecutive wins, which has only happened once before in the pageant’s history.

Natasha wowed crowds at the national costume competition last week and on Friday impressed during the preliminary round

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Miss Mexico crowned Miss Universe 2021

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By AFP Time of article published 16m ago

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Washington – Miss Mexico was crowned Miss Universe on Sunday in Florida, after fellow contestant Miss Myanmar used her stage time to draw attention to the bloody military coup in her country.

Sunday night marked the Miss Universe competition’s return to television, after the pageant was cancelled in 2020 for the first time due to the coronavirus pandemic.

Andrea Meza, 26, finished first ahead of the Brazilian and Peruvian finalists in a flashy televised event, hosted by American actor Mario Lopez and television personality Olivia Culpo.

Former Miss Universe contestants Cheslie Kryst, Paulina Vega and Demi-Leigh Tebow (who won the title in 2017) served as competition analysts and commentators, and a panel of eight women determined the winner.

Dressed in a sparkling red evening gown, Meza tearfully walked the catwalk as Miss Universe for the first time, before rushing back for a group hug with the other competitors.

Meza beat more than 70 contestants from around the globe in the 69th installment of Miss Universe, which was held at the Hard Rock Hotel & Casino in Hollywood, Florida.

In the days leading up to the final competition, Miss Myanmar Thuzar Wint Lwin, who made the top 21, made waves when she used her time in the spotlight to bring attention to the coup in her country.

“Our people are dying and being shot by the military every day,” she said during her biographical video, which showed photos of her taking part in the anti-coup protests. “Therefore I would like to urge everyone to speak out about Myanmar.”

Natasha Joubert, Miss Universe South Africa 2020 competes on stage in Ema Savahl swimwear during the MISS UNIVERSE® Preliminary Competition.

She also won the award for best national costume: during that competition segment on Thursday, she wore an outfit beaded in traditional Burmese patterns and held up a sign that said, “Pray for Myanmar.”

Myanmar has been in uproar since February 1, when the army ousted civilian leader Aung San Suu Kyi.

At least 796 people have been killed by security forces since then, according to a local monitoring group, while nearly 4 000 people are behind bars.

Miss Singapore Bernadette Belle Ong – who did not make the top 21 – also used the national costume portion to make a political statement.

Dressed in a glittering red bodysuit and matching thigh-high boots, she turned around to reveal her cape – in the colours of the Singaporean flag – was painted with the words “Stop Asian Hate.”

“What is this platform for if I can’t use it to send a strong message of resistance against prejudice and violence?” she wrote on Instagram alongside pictures of her outfit.

The United States in particular has seen a surge in anti-Asian violence in the past year, which activists have blamed on former president Donald Trump’s rhetoric, especially his repeated description of Covid-19 as the “China virus.”

The pageant has also drawn criticism in the past for objectifying the contestants.

In recent years, the competition has shifted image, focusing more on female empowerment and activism.

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