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Astronomers Find Stream of Early Universe Stars, Torn Apart by Our Own Galaxy

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Astronomers have discovered a mysterious stream of ancient stars at the distant edges of the galaxy: a strange stellar breed so unlike any we’ve seen before, they may very well be the last of their kind.

 

This unusual collection of stars – called the ‘Phoenix stream’, after the Phoenix constellation in which they are visible – is what’s known as a stellar stream: an elongated chain of stars that used to exist in a spherical form, known as a globular cluster.

Such clusters can be torn asunder by a galaxy’s gravitational forces, in which case their globular form becomes warped, stretching out into a ghostly caravan of stars, fated to distantly orbit a faraway galactic core.

010 stellar stream 2(James Josephides/Swinburne Astronomy Productions/S5 Collaboration)

Above: Artist’s impression of the stellar stream wrapping around the Milky Way.

Neither stellar streams nor globular clusters are new to science, but there’s something about the Phoenix stream that is. Its chemistry is different to any globular cluster we’ve ever seen, almost like it doesn’t belong here.

“We can trace the lineage of stars by measuring the different types of chemical elements we detect in them, much like we can trace a person’s connection to their ancestors through their DNA,” explains astronomer Kyler Kuehn from the Lowell Observatory in Arizona.

 

“It’s almost like finding someone with DNA that doesn’t match any other person, living or dead.”

There are around 150 known globular clusters in the Milky Way, all of which exist in what’s called the galactic halo – a tenuous spherical structure that envelops the relatively flat galactic disk, where most of a galaxy’s stars otherwise congregate.

Out in the fringes of the halo, though, there are still plenty of stars assembled inside the globular clusters. Each cluster can contain hundreds of thousands of stars, and observations of the clusters in the Milky Way have shown that all clusters demonstrate a certain consistency in their stellar chemistry: the stars in the clusters are enriched with ‘heavier’ chemical elements that are more massive than hydrogen and helium.

After the Big Bang, theory holds that all the gas in the Universe was made up of either hydrogen or helium, which in turn formed the Universe’s first stars. Other elements, such as oxygen, carbon, and magnesium, only became possible much later via the fusion mechanisms of subsequent generations of stars.

The chemical legacy of those later fusion mechanisms is all around us, as a certain proportion of heavier elements has been observed in all our galaxy’s globular customers. That is, until now.

This chemical threshold – called the metallicity floor – is not obeyed by the Phoenix stream, which demonstrates less heavy elements in its stars than we thought was theoretically possible for such a celestial structure.

“This stream comes from a cluster that, by our understanding, shouldn’t have existed,” explains astronomer Daniel Zucker from Macquarie University in Australia.

 

Or at least, it shouldn’t exist now, could be another way of putting it.

Observations of the Phoenix stream conducted by an international team of researchers as part of the Southern Stellar Stream Spectroscopic Survey Collaboration have revealed that its “metal abundance is substantially below the empirical metallicity floor”, the authors explain in their new study.

Up until now, the metallicity floor was a useful way of classifying a scientific constant seen across all present-day globular clusters. It still is, as it happens – but the Phoenix stream is no present-day globular cluster.

The team thinks it may be a sole survivor: a celestial relic of a bygone age in the early Universe, when stars made their light in different ways.

“One possible explanation is that the Phoenix stream represents the last of its kind, the remnant of a population of globular clusters that was born in radically different environments to those we see today,” says astronomer Ting Li from Carnegie Observatories in Pasadena.

Lots of questions remain, of course. If the Phoenix stream is a remnant of a relic from the early Universe, is it the only one? Do others also exist, hidden in the vastness of the galactic halo?

 

“In astronomy, when we find a new kind of object, it suggests that there are more of them out there,” says astronomer Jeffrey Simpson from the University of New South Wales (UNSW) in Australia.

If other old travellers are still on the trail, we don’t have forever to find them. Like globular clusters, stellar streams are not immortal things. Once they’re stretched out into a string of stars, it’s only a matter of time before they disband, and disperse throughout the galaxy.

“Who knows how many relics like the Phoenix stream might be hiding in the Milky Way’s halo?” wonders German astronomer J. M. Diederik Kruijssen from Heidelberg University, who wasn’t involved in the study but has authored a commentary on it.

“Now that the first one has been found, the hunt is on.”

The findings are reported in Nature.

 

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Women in the newsroom: Why South Africa leads the way

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Mahlatse Mahlase is group editor-in-chief of Eyewitness News, a major broadcaster in South Africa. It’s a role she would have been unlikely to fill 30 years ago, under the apartheid regime, whose hierarchy put Black women on a bottom tier.

But no matter where you look in the world, women’s leadership in the news media has lagged – and still does. South Africa, in fact, is a relative success story. Today, women lead nearly half of the country’s major publications and broadcasters, according to a recent analysis by Oxford University. That puts it ahead of the United States, the United Kingdom, and even countries held up as models of gender parity, like Finland.

Yet South African women’s gains have been especially hard-won, and incomplete. Women hold few of journalism’s purse strings, for instance. 

Ms. Mahlase says she has reflected on representation through a new prism since she gave birth seven months ago to her first child, a boy. 

“I want my son to grow up in a world where he has female bosses,” she says. “I want him to grow up listening to women experts on the radio, hearing them as contributors to changing the world and not just as victims of an unfair system.”

Johannesburg

Nwabisa Makunga can point to the exact moment she knew she would become a journalist.

It was April 1993 and she was 11 years old, watching the TV broadcast of the funeral of assassinated anti-apartheid leader Chris Hani with her family in their living room. The presenter was a Black reporter named Noxolo Grootboom, and her powerful tribute to Mr. Hani brought Ms. Makunga’s parents to tears.

“She was a woman who looked like me, who spoke like me, telling the story of a man who had been so important to people from my community,” she recalls. “I said to myself – this is what I’m going to do. I’m going to be like Noxolo, and I’m going to tell stories.”

Three decades later, Ms. Makunga is the editor-in-chief of the Sowetan, one of South Africa’s most-circulated daily newspapers. She is part of a generation of women who have risen through the ranks to take leadership of many of the country’s most important news outlets. Today, these women – most of them Black, Asian, and multiracial – lead nearly half the country’s major publications and broadcasters, according to a recent analysis by Oxford University. That makes the country a global leader for women’s leadership in the media, putting it ahead of the United States, the United Kingdom, and even countries held up as models of gender parity, like Finland.

And the achievement is doubly remarkable in South Africa, where only a generation ago the entire country was run largely by white men. Editors like Ms. Makunga grew up not only with few role models who looked like them, but also in a world where the media was used as a weapon of the apartheid regime, premised on white supremacy – enforcing a hierarchy in which they were the bottom tier.

Alexander Joe/AFP/Getty Images/File

A vendor sells a Daily Sun edition honoring former South African President Nelson Mandela’s birthday on July 18, 2013. The country’s transition to democracy opened up opportunities for many of today’s journalists.

Hard-won gains

Even after apartheid formally ended, these editors came up in newsrooms where its effects lingered. They were told their accents were “too African,” or their looks “too tempting.” Even as the newsrooms around them began to change from mostly white to mostly not, they still found themselves edged out of the pub trips and golf games where their male colleagues networked their way to the top.

“Make no mistake: Those statistics changing are the result of a fight,” says Mahlatse Mahlase, group editor-in-chief of Eyewitness News, a major breaking-news broadcaster. Women in South Africa’s newsrooms “have fought racism and they’ve also fought the patriarchy. The discrimination came from every side.”

Although they’ve now arrived, many of these same leaders note that South Africa’s media transformation remains incomplete. Women hold few of journalism’s purse strings, for instance. Just 19% of the board members at media companies here are female, according to a 2018 academic study of women in the media called “Glass Ceilings.” The vast majority of the country’s major media houses have a male CEO.

And while the proportion of Black, Asian, and multiracial women in the top echelons of South African media companies has grown from 6% in 2006 to 30% in 2018, that number still lags, in a country where they represent 46% of the population, according to the Glass Ceilings survey. Once they get there, meanwhile, they’re often placed under intense scrutiny and pressure.

“When men get to the top of their profession, they’re celebrated. When women get there, particularly Black women, there’s backlash, there’s trolling, there’s bullying,” says Glenda Daniels, an associate professor of media studies at the University of the Witwatersrand in Johannesburg and the co-author of the Glass Ceilings study. She uses the term “Black” as it is frequently applied in South Africa, to describe anyone who is not white. “Women at the top find they’re often exhausted just proving over and over that they deserve to be in the room.”

“Newsrooms figured out they needed to mimic what was happening in society so they wouldn’t end up on the wrong side of history.” – Mapula Nkosi, editor of the Daily Sun

Coming up the ladder

In 1994, the same year Nelson Mandela took the oath as South Africa’s first Black president, an ambitious young reporter named Mapula Nkosi walked into the Johannesburg newsroom of the Weekly Mail, which made its name opposing apartheid, to begin her career as a cadet reporter.

When she looked up the ranks, she says, she saw only men. But all around her, the country had a new buzzword: transformation. The process was often fuzzy, but the objective was clear: The structures that ruled the country should look more like the people who lived in it.

“Those newsrooms figured out they needed to mimic what was happening in society so they wouldn’t end up on the wrong side of history,” says Ms. Nkosi, now the editor of the Daily Sun, the country’s most-circulated daily newspaper. “The whole time I was coming up I had people on one side of me saying, ‘We don’t understand why you’re in this position,’ and people on the other side saying, ‘We are so excited to see where you go.’”

Those competing forces followed many of South Africa’s women journalists through their rise. Each time they pulled themselves up another rung on the ladder, they heard whispers – that they only got this job because leadership wanted a woman, that they’d never make it.

But when they did, the conversation changed.

“When you do well, you become almost genderless,” says Paula Fray, a media consultant and the first woman to edit the Saturday Star, a major South African newspaper. “But if you don’t do well, then your failings represent your whole gender.”

Meanwhile, women leaders in the newsroom “carry the added responsibility of making these environments more welcoming for women,” says Mary Papayya, a veteran journalist and editor who now sits on the board of the South African Broadcasting Corp. That, she notes, is a particularly difficult task at a time when many outlets have seen their budgets slashed and are now contending with a pandemic that has made news reporting both more dangerous and less lucrative.

And the fight for change goes beyond who sits in the corner office. In South Africa, like many countries, men are disproportionately both the experts and subjects of news stories. A recent analysis of the South African media’s coverage of the COVID-19 pandemic by the organization Media Monitoring Africa, for instance, found that 80% of those quoted in stories about the virus were men.

Ms. Mahlase, the radio news editor, says she sees these kinds of statistics through a new prism since she gave birth seven months ago to her first child, a boy. 

“I want my son to grow up in a world where he has female bosses,” she says. “I want him to grow up listening to women experts on the radio, hearing them as contributors to changing the world and not just as victims of an unfair system.”

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Women in the newsroom: Why South Africa leads the way

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Mahlatse Mahlase is group editor-in-chief of Eyewitness News, a major broadcaster in South Africa. It’s a role she would have been unlikely to fill 30 years ago, under the apartheid regime, whose hierarchy put Black women on a bottom tier.

But no matter where you look in the world, women’s leadership in the news media has lagged – and still does. South Africa, in fact, is a relative success story. Today, women lead nearly half of the country’s major publications and broadcasters, according to a recent analysis by Oxford University. That puts it ahead of the United States, the United Kingdom, and even countries held up as models of gender parity, like Finland.

Yet South African women’s gains have been especially hard-won, and incomplete. Women hold few of journalism’s purse strings, for instance. 

Ms. Mahlase says she has reflected on representation through a new prism since she gave birth seven months ago to her first child, a boy. 

“I want my son to grow up in a world where he has female bosses,” she says. “I want him to grow up listening to women experts on the radio, hearing them as contributors to changing the world and not just as victims of an unfair system.”

Johannesburg

Nwabisa Makunga can point to the exact moment she knew she would become a journalist.

It was April 1993 and she was 11 years old, watching the TV broadcast of the funeral of assassinated anti-apartheid leader Chris Hani with her family in their living room. The presenter was a Black reporter named Noxolo Grootboom, and her powerful tribute to Mr. Hani brought Ms. Makunga’s parents to tears.

“She was a woman who looked like me, who spoke like me, telling the story of a man who had been so important to people from my community,” she recalls. “I said to myself – this is what I’m going to do. I’m going to be like Noxolo, and I’m going to tell stories.”

Three decades later, Ms. Makunga is the editor-in-chief of the Sowetan, one of South Africa’s most-circulated daily newspapers. She is part of a generation of women who have risen through the ranks to take leadership of many of the country’s most important news outlets. Today, these women – most of them Black, Asian, and multiracial – lead nearly half the country’s major publications and broadcasters, according to a recent analysis by Oxford University. That makes the country a global leader for women’s leadership in the media, putting it ahead of the United States, the United Kingdom, and even countries held up as models of gender parity, like Finland.

And the achievement is doubly remarkable in South Africa, where only a generation ago the entire country was run largely by white men. Editors like Ms. Makunga grew up not only with few role models who looked like them, but also in a world where the media was used as a weapon of the apartheid regime, premised on white supremacy – enforcing a hierarchy in which they were the bottom tier.

Alexander Joe/AFP/Getty Images/File

A vendor sells a Daily Sun edition honoring former South African President Nelson Mandela’s birthday on July 18, 2013. The country’s transition to democracy opened up opportunities for many of today’s journalists.

Hard-won gains

Even after apartheid formally ended, these editors came up in newsrooms where its effects lingered. They were told their accents were “too African,” or their looks “too tempting.” Even as the newsrooms around them began to change from mostly white to mostly not, they still found themselves edged out of the pub trips and golf games where their male colleagues networked their way to the top.

“Make no mistake: Those statistics changing are the result of a fight,” says Mahlatse Mahlase, group editor-in-chief of Eyewitness News, a major breaking-news broadcaster. Women in South Africa’s newsrooms “have fought racism and they’ve also fought the patriarchy. The discrimination came from every side.”

Although they’ve now arrived, many of these same leaders note that South Africa’s media transformation remains incomplete. Women hold few of journalism’s purse strings, for instance. Just 19% of the board members at media companies here are female, according to a 2018 academic study of women in the media called “Glass Ceilings.” The vast majority of the country’s major media houses have a male CEO.

And while the proportion of Black, Asian, and multiracial women in the top echelons of South African media companies has grown from 6% in 2006 to 30% in 2018, that number still lags, in a country where they represent 46% of the population, according to the Glass Ceilings survey. Once they get there, meanwhile, they’re often placed under intense scrutiny and pressure.

“When men get to the top of their profession, they’re celebrated. When women get there, particularly Black women, there’s backlash, there’s trolling, there’s bullying,” says Glenda Daniels, an associate professor of media studies at the University of the Witwatersrand in Johannesburg and the co-author of the Glass Ceilings study. She uses the term “Black” as it is frequently applied in South Africa, to describe anyone who is not white. “Women at the top find they’re often exhausted just proving over and over that they deserve to be in the room.”

“Newsrooms figured out they needed to mimic what was happening in society so they wouldn’t end up on the wrong side of history.” – Mapula Nkosi, editor of the Daily Sun

Coming up the ladder

In 1994, the same year Nelson Mandela took the oath as South Africa’s first Black president, an ambitious young reporter named Mapula Nkosi walked into the Johannesburg newsroom of the Weekly Mail, which made its name opposing apartheid, to begin her career as a cadet reporter.

When she looked up the ranks, she says, she saw only men. But all around her, the country had a new buzzword: transformation. The process was often fuzzy, but the objective was clear: The structures that ruled the country should look more like the people who lived in it.

“Those newsrooms figured out they needed to mimic what was happening in society so they wouldn’t end up on the wrong side of history,” says Ms. Nkosi, now the editor of the Daily Sun, the country’s most-circulated daily newspaper. “The whole time I was coming up I had people on one side of me saying, ‘We don’t understand why you’re in this position,’ and people on the other side saying, ‘We are so excited to see where you go.’”

Those competing forces followed many of South Africa’s women journalists through their rise. Each time they pulled themselves up another rung on the ladder, they heard whispers – that they only got this job because leadership wanted a woman, that they’d never make it.

But when they did, the conversation changed.

“When you do well, you become almost genderless,” says Paula Fray, a media consultant and the first woman to edit the Saturday Star, a major South African newspaper. “But if you don’t do well, then your failings represent your whole gender.”

Meanwhile, women leaders in the newsroom “carry the added responsibility of making these environments more welcoming for women,” says Mary Papayya, a veteran journalist and editor who now sits on the board of the South African Broadcasting Corp. That, she notes, is a particularly difficult task at a time when many outlets have seen their budgets slashed and are now contending with a pandemic that has made news reporting both more dangerous and less lucrative.

And the fight for change goes beyond who sits in the corner office. In South Africa, like many countries, men are disproportionately both the experts and subjects of news stories. A recent analysis of the South African media’s coverage of the COVID-19 pandemic by the organization Media Monitoring Africa, for instance, found that 80% of those quoted in stories about the virus were men.

Ms. Mahlase, the radio news editor, says she sees these kinds of statistics through a new prism since she gave birth seven months ago to her first child, a boy. 

“I want my son to grow up in a world where he has female bosses,” she says. “I want him to grow up listening to women experts on the radio, hearing them as contributors to changing the world and not just as victims of an unfair system.”

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Trump Administration Penalizes Chinese Officials for Hong Kong Crackdown

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WASHINGTON — The Trump administration on Friday imposed sanctions on 11 senior Chinese Communist Party officials and their Hong Kong allies, including chief executive Carrie Lam, over their role in cracking down on political dissent in the southern Chinese territory.

These are the first sanctions against officials from China and Hong Kong over suppression of pro-democracy protests and dissent in the territory. They are being imposed as actions following an executive order President Trump signed last month seeking to punish China for its repression in Hong Kong.

“The United States stands with the people of Hong Kong and we will use our tools and authorities to target those undermining their autonomy,” Steven T. Mnuchin, the Treasury secretary, said in a statement.

The action is another in a series of measures the Trump administration has taken in recent months to ratchet up pressure on Beijing. Last month, the administration imposed sanctions on the Chinese government, including a senior member of the Communist Party, over human rights abuses against the largely Muslim Uighur minority.

Beijing announced in June that it was imposing a new national security law in Hong Kong to grant security agencies expansive powers to crack down on dissent.

Since then, American officials have debated how to get Beijing to roll back the law or how to penalize the action.

Last month, Mr. Trump signed an executive order ending the special status that the United States grants Hong Kong in diplomatic and trade relations, saying Hong Kong was no longer an autonomous entity, and officials are now beginning to treat the territory like mainland China.

Some administration officials had wanted Mr. Trump to announce during the signing that his government was imposing sanctions on Ms. Lam and other officials in China and Hong Kong. The president declined to do so then.

The current flurry of actions against China dovetails with a core part of Mr. Trump’s campaign strategy. His campaign aides are trying to show Mr. Trump is hitting China hard in order to shift the national conversation from his failures on managing the coronavirus pandemic and the economy.

The initial virus outbreak began in central China, and Mr. Trump has blamed Chinese officials for failing to contain it, though he also praised China’s leader, Xi Jinping, for efforts this winter.

Some of the administration’s China hawks are trying to set the two nations on a course for long-term confrontation and ensure that relations remain in a state of open rivalry even if Democratic candidate Joseph R. Biden Jr. wins the November election.

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