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For the first time astronomers have directly observed evidence of white dwarf stars solidifying into giant crystals.

Researchers at the University of Warwick believe our skies are filled with these enormous crystals, according to observations made with the European Space Agency’s Gaia satellite.

Stars like our own sun which aren’t large enough to collapse into black holes will become white dwarfs once they reach the end of their life-cycle.

At their core these stars are solid and made of oxygen and carbon due to what’s called a phase transition – similar to water turning into ice, only at much higher temperatures.

The discovery, led by Dr Pier-Emmanuel Tremblay and published in the journal Nature, means that white dwarf stars could be potentially billions of years older than previously thought.

Because white dwarf stars are some of the oldest stellar objects in the universe, they offer scientists a good way to estimate the age of neighbouring stars.

The team in Warwick studied 15,000 white dwarf candidates within around 300 light years of Earth and measured their colour and luminosity for clues about their composition.

What they found surprised them.

A black hole
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Stars too small to become black holes will become white dwarfs

There was a “pile-up”, or “an excess in the number of stars at specific colours and luminosities that do not correspond to any single mass or age”.

These excess corresponded to a particular time in the evolution in a star in which they are expected to slow their cooling process and thus age more slowly.

Dr Tremblay said: “This is the first direct evidence that white dwarfs crystallise, or transition from liquid to solid.

“It was predicted 50 years ago that we should observe a pile-up in the number of white dwarfs at certain luminosities and colours due to crystallisation and only now this has been observed.

“All white dwarfs will crystallise at some point in their evolution, although more massive white dwarfs go through the process sooner.

“This means that billions of white dwarfs in our galaxy have already completed the process and are essentially crystal spheres in the sky.

“The sun itself will become a crystal white dwarf in about 10 billion years,” added Dr Tremblay, reminding us that these crystals – although a new discovery – are the usual end for stars.

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French nappies found to contain weedkiller and other potentially toxic chemicals | World News

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Potentially toxic substances, including a widely-used weedkiller linked to cancer, have been discovered in nappies made and sold in France.

Environment agency ANSES revealed its findings in a new study published on Wednesday, with scientists testing 23 types of nappies as they were worn by children.

The tests uncovered butylphenyl methylpropional – used in beauty products – and some aromatic hydrocarbons.

The weedkiller chemical found was glyphosate, which has been linked to cancer and had been subjected to attempts by some European leaders to have it banned.

Regarding its discovery in nappies made in the country, the government said it was vital that manufacturers and retailers ensured the substance was removed.

In a joint statement, the health, environment and finance ministries said: “We call on manufacturers and retailers to take measures within the next 15 days to eliminate these substances from babies’ nappies.”

Emmanuel Macron wants Europe to have a dedicated army
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Emmanuel Macron has previously said he wants glyphosate to be banned

Health minister Agnes Buzyn also moved to assure parents that there was no immediate risk to their children, and said the report was “a precaution to protect our children from possible effects”.

She added: “Obviously we should continue putting nappies on our babies – we’ve been doing that for at least 50 years.”

President Emmanuel Macron has previously said he wanted the glyphosate to be completely phased out, but farmers are likely to be exempt as there are no credible alternatives.

As well as being potentially dangerous to humans, scientists have warned that the controversial pesticide could also be killing bees.

But it remains registered in around 130 countries, including the UK, where it is commonly used to spray pests.

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Venezuelan opposition leader declares himself president amid unrest | World News

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Venezuela’s opposition leader has declared himself the new president amid riots which have led to several deaths.

Juan Guaido was met with cheering support after naming himself interim president, raising his right hand as he said he was “formally assuming the responsibility of the national executive”.

Soon after, US president Donald Trump formally recognised Mr Guaido as the interim president of Venezuela.

A statement from the White House encouraged other western nations to make the same move.

Nicolas Maduro was sworn in for a contested second term two weeks ago but has been met by international condemnation.

Thousands of Venezuelans have protested against Mr Maduro, accusing him of usurping power and demanding he step down.

Millions have fled as the country reels from a crushing economic crisis. Those who are forced to stay are going hungry.

The Venezuelan parliament is not likely to convene until Thursday at the earliest.

Mr Maduro was re-elected last month but the country’s opposition does not recognise the election and says it was fraudulent.

The US recognition of Mr Guaido will mount pressure on Mr Maduro to step down.

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‘I can’t say I’m sorry’: Trump hat teen Nick Sandmann defends himself over Native American encounter | US News

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A US high school student has said he wished he “walked away and avoided” his encounter with a Native American protester.

Nick Sandmann was filmed apparently smirking while standing just a few feet from Nathan Phillips at the Lincoln Memorial in Washington on Friday in a video that has gone viral.

But the teenager said he did not intend to be disrespectful, insisting “I’d like to talk to [Mr Phillips]”

“I mean, in hindsight, I wish we could’ve walked away and avoided the whole thing. But I can’t say that I’m sorry for listening to him and standing there,” he told NBC’s Today programme.

Nick Sandmann (L) and Nathan Phillips were filmed at the Lincoln Memorial
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Nick Sandmann (L) and Nathan Phillips were filmed at the Lincoln Memorial

Asked if he felt he owed anyone an apology or has assumed fault for the clash, he instead blamed a group of black men styling themselves as Hebrew Israelites who were also there.

The men were filmed taunting and insulting both the indigenous people gathered with Mr Phillips and the boys, many of whom, including Sandmann, wore red hats bearing President Trump’s “Make America Great Again” slogan.

“They started shouting a bunch of homophobic, racist, derogatory comments at us. I heard them call us incest kids, bigots, racists. They called us f*****s,” Nick Sandmann said.

The Hebrew Israelites were filmed taunting the boys. Pic: NBC
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The Hebrew Israelites were filmed taunting the boys. Pic: NBC

The Covington Catholic High School students, who were in Washington for an anti-abortion rally, outnumbered their aggressors but the teenager said he “definitely felt threatened.”

Nathan Phillips, a tribal elder, activist and Vietnam War veteran, was singing and playing a drum as he took part in an indigenous people’s march.

He locked eyes with Nick Sandmann while around them some of the teenager’s classmates from the private, all-male school in Kentucky, were seen dancing and jumping around, apparently mocking Mr Phillips.

Donald Trump wearing one of his MAGA hats at a campaign rally
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Donald Trump wearing one of his MAGA hats at a campaign rally

Some were also wearing “Make America Great Again” hats and sweatshirts and one removed his top.

President Trump’s press secretary Sarah Huckabee Sanders said on Wednesday the White House has “reached out and voiced our support” to Nick Sandmann and his fellow students.

She said no one understands better than Donald Trump when the media jumps to conclusions and “attacks you for something you may or may not have done.”

On Tuesday, Mr Trump defended the students, tweeting that they had been “smeared by the media” and had become “symbols of Fake News and how evil it can be”.

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