NASA probe beams back ultraviolet images of Martian atmosphere

October 18, 2016

Washington, Oct 18: In a first, NASA's MAVEN spacecraft has beamed back ultraviolet images of Mars that unveils dynamic, previously invisible activities in the atmosphere of the red planet such as change in ozone levels over the seasons and formation of clouds.master

The images were taken by the Imaging UltraViolet Spectrograph (IUVS) on the Mars Atmosphere and Volatile Evolution mission (MAVEN) - a space probe designed to study the Martian atmosphere while orbiting Mars.

These were then used to make this movie of rapid cloud formation on Mars on July this year.

The movie uses four MAVEN images to show about seven hours of Mars rotation during this period, and interleaves simulated views that would be seen between the four images.

"MAVEN obtained hundreds of such images in recent months, giving some of the best high-resolution ultraviolet coverage of Mars ever obtained," said Nick Schneider from the University of Colorado, Boulder in the US.

Nightside images show ultraviolet (UV) "nightglow" emission from nitric oxide (NO). Nightglow is a common planetary phenomenon in which the sky faintly glows in the complete absence of external light.

Mars' nightside atmosphere emits light in the ultraviolet due to chemical reactions that start on Mars' dayside.

Ultraviolet light from the Sun breaks down molecules of carbon dioxide and nitrogen, and the resulting atoms are carried around the planet by high-altitude wind patterns that encircle the planet.

On the nightside, these winds bring the atoms down to lower altitudes where nitrogen and oxygen atoms collide to form nitric oxide molecules. The recombination releases extra energy, which comes out as ultraviolet light.

Scientists predicted NO nightglow at Mars, and prior missions detected its presence, but MAVEN has returned the first images of this phenomenon in the Martian atmosphere.

Splotches and streaks appearing in the images occur where NO recombination is enhanced by winds.

Such concentrations are clear evidence of strong irregularities in Mars' high altitude winds and circulation patterns. These winds control how Mars' atmosphere responds to its very strong seasonal cycles.

Dayside images show the atmosphere and surface near Mars' south pole in unprecedented ultraviolet detail. They were obtained as spring comes to the southern hemisphere.

Ozone is destroyed when water vapour is present, so ozone accumulates in the winter polar region where the water vapour has frozen out of the atmosphere.

The images show ozone lasting into spring, indicating that global winds are inhibiting the spread of water vapour from the rest of the planet into winter polar regions.

MAVEN observations also show afternoon cloud formation over the four giant volcanoes on Mars.
Clouds are a key to understanding a planet's energy balance and water vapour inventory, so these observations will be valuable in understanding the daily and seasonal behaviour of the atmosphere, researchers said.

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Agencies
June 24,2020

Washington, Jun 24: Twitter has once again flagged a tweet from US President Donald Trump which promoted violence by saying if protesters tried to set up an "autonomous zone" in Washington, DC they would be met with "serious force".

This is the fourth time Twitter has red flagged Trump's tweet for glorifying violence or violating its policies.

Trump has been critical of the "autonomous zone" in Seattle, an area occupied by protestors for much of this month.

"We've placed a public interest notice on this Tweet for violating our policy against abusive behaviour, specifically, the presence of a threat of harm against an identifiable group," Twitter's safety team tweeted late Tuesday.

Trump had tweeted: "There will never be an ‘Autonomous Zone' in Washington, D.C., as long as I'm your President. If they try they will be met with serious force!"

Twitter earlier labeled a video tweeted by him which mocked CNN as manipulated media.

According to Twitter, "this Tweet has been labeled per our synthetic and manipulated media policy to give people more context".

In May, Twitter labeled two Trump tweets that made false claims about mail-in ballots in California.

Twitter later labeled another Trump tweet glorifying violence in which he said, "when the looting starts, the shooting starts."

Facebook also removed a Trump campaign ad featuring a symbol used by Nazis for political dissenters, saying the ad violated its policies.

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News Network
July 2,2020

Los Angeles, Jul 2: New daily coronavirus cases in the United States soared past 50,000 for the first time Wednesday, as the World Health Organization delivered a grave warning that the global pandemic is accelerating.

Restaurants, bars and beaches in the world's worst-hit nation closed from California to Florida, as states reeling from yet another surge in the deadly virus braced for Independence Day festivities.

Global infections have hit their highest level in the past week, WHO data showed, with chief Tedros Adhanom Ghebreyesus saying new cases topped "160,000 on every single day."

The grim milestone came as the European Union left the United States, Brazil and Russia off its final list of nations safe enough to allow residents to enter its borders.

With more than 52,000 new COVID-19 cases in the United States alone in the past 24 hours, according to a Johns Hopkins University tally, several US states imposed 14-day quarantines on visitors in the buildup to the long weekend's July 4 celebrations.

California suspended indoor dining at restaurants in Los Angeles and several counties, while New York scrapped plans to allow restaurants to seat customers inside from next week.

President Donald Trump reiterated his belief that the contagion will "at some point... sort of just disappear, I hope."

But the US leader who has yet to be seen in public wearing a face mask during the pandemic added he would have "no problem" doing so.

EU travel ban eased

The rollbacks came as the European Union reopened its borders to visitors from 15 countries.

The bloc hopes relaxing restrictions on countries from Algeria to Uruguay will breathe life into its tourism sector, choked by a ban on non-essential travel since mid-March.

Travelers from China, where the virus first emerged late last year, will be allowed to enter the EU only if Beijing reciprocates.

And Brazil -- which has suffered the most deaths globally for the last week, and is the second-worst affected country overall -- was excluded entirely.

It topped 60,000 total fatalities Wednesday, after suffering 1,000 deaths in just 24 hours.

However, with over 10 million known infections worldwide and more than 500,000 deaths, the pandemic is "not even close to being over", the WHO warned.

Data provided by the UN health agency for the seven days from June 25-July 1 showed the highest number of new daily cases ever recorded came on June 28, when over 189,500 new cases were registered worldwide.

'Dutch brothels reopen'

According to the United Nations, the coronavirus crisis could cost global tourism and related sectors from $1.2 to $3.3 trillion in lost revenue.

Greece, which has suffered fewer than 200 virus deaths, has seen its economy hit hard by lockdowns and travel restrictions -- all but ending its lucrative tourism season before it began.

Romanian Cojan Dragos was "the first tourist" in one Corfu hotel after driving there with his wife and daughter.

"We have the whole hotel just for us," he told news agency.

Separately, Spain and Portugal held a ceremony as they reopened their land border.

The Netherlands also confirmed the reopening Wednesday of another tourist draw -- its brothels and red-light districts.

"I'm totally booked," said sex worker Foxxy, adding that she had held a "little party" when she heard restrictions would be lifted.

Clusters spur new lockdowns

Russia did not make the EU's list of approved countries so its citizens will be absent from the bloc's tourist hot-spots.

The country, however, enjoyed a public holiday Wednesday as it voted in a referendum to approve constitutional changes allowing President Vladimir Putin to stay in power for another 16 years.

Putin was forced to postpone the vote in April as his government tackled an outbreak that has infected almost 650,000 people -- the third-highest in the world.

In other countries, clusters are still causing problems.

Parts of the Australian city of Melbourne suffered sharp rises in infections, spurring new stay-at-home measures.

The Palestinian Authority announced a five-day lockdown across the West Bank after a surge in confirmed cases.

And textile factories in the central British city of Leicester were suggested as the reason for a spike in infections that has prompted the reimposition of local restrictions.

Americas spike

In the United States, spikes across southern and western states are driving a surge in national infections.

Texas, which again smashed its daily COVID-19 record with over 8,000 new cases, joined Florida and California in closing some beaches for the upcoming holiday weekend.

Apple announced it would close another 30 US stores on Thursday, half of them in California.

A further 700 deaths nationwide took the US past 128,000 deaths in total.

The Pan American Health Organization warned that the death count in Latin America and the Caribbean could quadruple to more than 400,000 by October without stricter public health measures.

The US government announced this week it had bought 92 percent of all remdesivir production -- the first drug to be shown to be relatively effective in treating COVID-19.

Britain and Germany, however, said Wednesday they had sufficient stocks of the drug.

'Corona baby'

In Britain, some 1,500 acts from Ed Sheeran and Coldplay to Paul McCartney and The Rolling Stones urged the county's government to save the live music industry, which has been collapsing because of the coronavirus.

But while lockdown measures have been a disaster for many, some have welcomed the chance to spend more quality time with hard-working partners.

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News Network
June 4,2020

New York, Jun 4: The Minneapolis police officer who used his knee to pin down George Floyd's neck before his death was the most experienced of the four officers involved in the arrest, with a record that included medals for bravery and 17 complaints against him, including one for pulling a woman out of her car during a speeding stop.

New details about Derek Chauvin and the other now-fired officers emerged Wednesday after prosecutors upgraded Chauvin's charge to second-degree murder and charged the others with aiding and abetting in a case that has convulsed the nation with protests over race and police brutality.

Heavily redacted personnel files show that Chauvin, a 19-year veteran of the force, was initially trained as a cook and served in the Army as a military police officer.

Eleven-year veteran and native Hmong speaker Tou Thao began as a community service officer and was the subject of six complaints.

The other two officers were relative newcomers to the department, including Thomas Lane, a former juvenile detention guard who did volunteer work with Somali refugees, and J. Alexander Kueng, who got his start in law enforcement by patrolling his college campus and a department store.

The files were notable for what they didn't include. Only one of the 17 complaints against Chauvin was detailed, none of the six against Thao were mentioned and there was no further detail about a 2017 excessive force lawsuit against Thao.

Records show that the 44-year-old Chauvin initially studied cooking before taking courses in law enforcement and doing two stints in the Army as a military police officer in the late 1990s, serving at Fort Benning, Georgia, and in Germany.

Chauvin became a Minneapolis police officer in 2001 and the lone reprimand in his file involved a 2007 incident when he was accused of pulling a woman out of her car after stopping her for going 10 mph (16 kph) over the speed limit.

Investigators found it was not necessary for Chauvin to remove the woman from the car and noted that his squad car video was turned off during the stop.

But Chauvin was also singled out for bravery. Files show he won two medals of valor, one in 2006 for being part of a group of officers who opened fire on a stabbing suspect who pointed a shotgun at them, and another in 2008 for a domestic violence incident in which Chauvin broke down a bathroom door and shot a suspect in the stomach.

He also won medals of commendation in 2008 after he and his partner tackled a fleeing suspect who had a pistol in his hand, and in 2009 for single-handedly apprehending a group of gang members while working as an off-duty security guard at the El Nuevo Rodeo, a Minneapolis nightclub.

Since his arrest, the former owner of the club, Maya Santamaria, said Chauvin and Floyd both worked as security guards there at various times but that she wasn't sure if they had known one another.

She said Chauvin was unnecessarily aggressive on nights when the club had a black clientele, quelling fights by dousing the crowd with pepper spray and calling in several police squad cars as backup, a tactic she called “overkill.”

Chauvin's wife, Kellie, a Laotian immigrant who became the first Hmong winner of the Mrs. Minnesota pageant, said shortly after his arrest last week that she intends to divorce him.

Before news of the upgraded charges, an attorney for Chauvin said he was not making any statements at this time. Lawyers for the others did not return messages seeking comment.

In cellphone video of the May 25 arrest of Floyd, Chauvin is shown pressing his knee onto Floyd's neck for more than eight minutes while Floyd cries out “I can't breathe” and eventually stops moving.

During much of the arrest, Kueng and Lane were helping Chauvin restrain Floyd. Thao was standing nearby keeping onlookers back.

According the complaint, at one point during the arrest, as Chauvin held Floyd down with his knee, Lane asked Chauvin twice whether they should roll Floyd over.

“No, staying put where we got him,” Chauvin replied, “I am worried about excited delirium or whatever,” Lane said. And Chauvin replied again, “That's why we have him on his stomach.” None of the three officers moved from their positions.

Lane joined the police early last year as a 35-year-old cadet — much older than most rookies — and became a full-fledged officer last December. He had no complaints in his file during his short time on the force.

On employment forms, the University of Minnesota graduate said he done volunteer work tutoring Somali youth and as a mentor helping at-risk elementary school students with reading and homework.”

Kueng, at 26 the youngest of the four officers, was also a recent recruit to the police force. He completed his year's probation just three months before the Floyd arrest.

His personnel file, which notes that he speaks, reads and writes Russian, did not include any commendations or disciplinary actions during his short time on force.

Kueng was a 2018 graduate of the University of Minnesota, where he worked part-time as part of the campus security force. He also worked nearly three years as a theft-prevention officer at Macy's.

Thao joined the police force part-time in 2008 while attending a community college. Before that, he worked as a security guard, a supermarket stocker and trainer at McDonald's.

City records show six complaints were filed against Thao, but there was no mention of that in the records released Wednesday. There also was no mention of a 2017 federal lawsuit accusing him and another officer of excessive force.

According to the lawsuit, Lamar Ferguson claimed that in 2014, Thao and his partner stopped him and beat him up while he was on his way to his girlfriend's house. The lawsuit was settled for $25,000 ___

Richmond reported from Madison, Wisconsin. Associated Press writer Scott Bauer in Madison and researcher Rhonda Shafner in New York contributed to this report.

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