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
May 4,2020

Washington, May 4: Anxious for an economic recovery, President Donald Trump fielded Americans' questions about decisions by some states to allow nonessential businesses to reopen while other states are on virtual lockdown due to the coronavirus.

After more than a month of being cooped up at the White House, Trump returned from a weekend at the Camp David presidential retreat in Maryland and participated in a “virtual” town hall, hosted Sunday night by Fox News Channel, from inside the Lincoln Memorial.

He pushed for an economic reopening, one his advisers believe will be essential for his reelection chances this November.

“We have to get it back open safely but as quickly as possible," Trump said.

The president acknowledged fear on both sides of the issue, some Americans worried about getting sick while others are concerned about losing jobs.

Though the administration's handling of the pandemic, particularly its ability to conduct widespread testing, has come under fierce scrutiny, the president defended the response and said the nation was ready to begin reopening.

“I'll tell you one thing. We did the right thing and I really believe we saved a million and a half lives,” the president said.

But he also broke with the assessment of his senior adviser and son-in-law, Jared Kushner, saying it was “too soon to say" if the federal government was overseeing a “success story."

Trump's impatience also flashed. While noting that states would go at their own pace in returning to normal, with ones harder hit by the coronavirus going slower, he said that “some states frankly I think aren't going fast enough" and singled out Virginia, which has a Democratic governor and legislature.

And he urged the nation's schools and universities to return to classes this fall.

But many public health experts believe that cannot be done safely until a vaccine is developed.

Trump declared Sunday that he believed one could be available by year's end although his own pandemic task force has predicated it could be another 18 months.

Federal guidelines that encouraged people to stay at home and practice social distancing expired late last week.

Debate continued over moves by governors to start reopening state economies that tanked after shopping malls, salons and other nonessential businesses were ordered closed in attempt to slow a virus that has killed more than 66,000 Americans, according to a tally of reported deaths by Johns Hopkins University.

The U.S. economy has suffered, shrinking at a 4.8 per cent annual rate from January through March, the government estimated last week. It was the sharpest quarterly drop since the 2008 financial crisis.

Roughly 30.3 million people have filed for unemployment aid in the six weeks since the outbreak forced employers to shut down and slash their workforces. It was the worst string of layoffs on record.

Larry Kudlow, Trump's top economic adviser, on Sunday predicted a “spectacular 2021” — with “the right set of policies” — on top of a rebound from July through December of this year.

He said on CNN's "State of the Union" that the administration would "pause” to review the effectiveness of trillions in economic relief spending before making any decision on whether additional aid is needed.

House Speaker Nancy Pelosi, D-Calif., said Thursday that state and local governments are seeking up to USD 1 trillion for coronavirus costs, The Senate planned to reopen Monday, despite the Washington area's continued status as a virus hot spot and with the region still under stay-at-home orders.

The House remains shuttered. The pandemic is forcing big changes at the tradition-bound Supreme Court: The justices will hear arguments, beginning Monday, by telephone for the first time since Alexander Graham Bell patented his invention in 1876.

Congressional Republicans are resisting calls by Democrats for emergency spending for states and local governments whose revenue streams all but dried up in recent weeks.

The GOP is counting on the country's reopening and the rebound promised by Trump as their best hope to forestall another big round of virus aid.

The leaders of California and Michigan are among governors under public pressure over lockdowns still in effect while states such as Florida, Georgia and Ohio are reopening.

Michigan Governor Gretchen Whitmer, a Democrat, said Sunday that the armed protesters who demonstrated inside her state's Capitol “depicted some of the worst racism” and “awful parts” of US history by showing up with Confederate flags, nooses and swastikas.

Trump had tweeted “LIBERATE” and named Michigan and other states in mid-April. In a new tweet Friday, he urged Whitmer to “make a deal” with the protesters. “These are very good people, but they are angry.

They want their lives back again, safely!” Trump said.

Despite the opposition of Michigan's Republican-controlled Legislature, Whitmer has extended a state of emergency declaration and directed most businesses statewide to remain closed.

Some people participating in other public protests across the US have not kept their distance from one another and have rallied without masks, not heeding public health recommendations.

Deborah Birx, coordinator of the White House coronavirus task force, called that behavior “devastatingly worrisome.”

She said people will feel guilty for the rest of their lives if they end up infected and unwittingly spread the virus to vulnerable family members.

“We need to protect each other at the same time we're voice our discontent,” she told CNN's “State of the Union.”

An overwhelming majority of Americans support stay-at-home orders and other efforts to slow the virus' spread, according to a recent survey from The Associated Press-NORC Center for Public Affairs Research.

Asked about states that are reopening before they meet benchmarks laid out in federal guidelines she helped write, Birx said the guidelines “are a pretty firm policy of what we think is important from a public health standpoint.”

She added that she and others have made it clear that people must continue practising social distancing, “scrupulous” hand washing and other measures to protect themselves and others.

Fox News Channel said it asked viewers to submit questions about reopening the country on the network's Twitter, Facebook and Instagram accounts for a chance to appear on the rare broadcast from the Lincoln Memorial. Trump spoke from the memorial's steps last July Fourth.

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News Network
June 13,2020

Paris, Jun 13: The coronavirus pandemic has killed 425,000 people since it emerged in China late last year, according to an AFP tally of official sources at 0130 GMT on Saturday.

A total of 425,282 deaths have now been recorded from 7,632,517 cases.

Europe has registered 186,843 deaths from 2,363,538 cases, but the epidemic is progressing most rapidly in Latin America, where there have been a total of 76,343 deaths recorded from 1,569,938 cases.

The United States remains the country with the most recorded deaths at 114,643, ahead of Brazil which on Friday became the second worst-hit nation with 41,828 deaths. Britain is next with 41,481 deaths, followed by Italy (34,223) and France (29,374).

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News Network
June 1,2020

Washington, Jun 1: Police fired tear gas outside the White House late Sunday as major US cities were put under curfew to suppress rioting as anti-racism protestors again took to the streets to voice fury at police brutality.

With the Trump administration branding instigators of six nights of rioting as domestic terrorists, there were more confrontations between protestors and police and fresh outbreaks of looting.

Violent clashes erupted repeatedly in a small park next to the White House, with authorities using tear gas, pepper spray and flash bang grenades to disperse crowds who lit several large fires and damaged property.

Local US leaders appealed to citizens to give constructive outlet to their rage over the death of an unarmed black man in Minneapolis, while night-time curfews were imposed in cities including Washington, Los Angeles and Houston.

One closely watched protest was outside the state capitol in Minneapolis' twin city of St. Paul, where several thousand people gathered before marching down a highway.

"We have black sons, black brothers, black friends, we don't want them to die. We are tired of this happening, this generation is not having it, we are tired of oppression," said Muna Abdi, a 31-year-old black woman who joined the protest.

"I want to make sure he stays alive," she added in reference to her son, aged three.

Hundreds of police and National Guard troops were deployed ahead of the protest.

At one point, some of the protestors who had reached a bridge were forced to scramble for cover when a truck drove at speed after having apparently breached a barricade.

The driver was later taken to hospital after the protestors hauled him from the vehicle, although there were no immediate reports of other casualties.

There were other large-scale protests in cities including New York and Miami.

Washington's mayor ordered a curfew from 11:00 pm until 6:00 am, as a report in the New York Times said that President Donald Trump had been rushed by Secret Service agents into an underground bunker at the White House on Friday night during an earlier protest.

Stores ransacked

Large-scale violence has rocked many US cities in recent days, and looters ransacked stores in a neighborhood of Philadelphia on Sunday.

In the Los Angeles suburb of Santa Monica, looting was reported at stores in a popular beachside shopping center.

Officials in LA -- a city scarred by the 1992 riots over the police beating of Rodney King, an African-American man -- imposed a curfew from 4:00 pm Sunday until dawn.

"Please, use your discretion and go early, go home, stay home and help us make sure that those who want to change this conversation from being about racial justice to be about burning things and looting things, don't win the day," the city's mayor Eric Garcetti said on CNN.

The shocking videotaped death last Monday of an unarmed black man, George Floyd, at the hands of police in Minneapolis ignited the nationwide wave of outrage over law enforcement's repeated use of lethal force against unarmed African Americans.

Floyd stopped breathing after Minneapolis police officer Derek Chauvin knelt on his neck for nearly nine minutes.

Chauvin has been charged with third-degree murder and is due to make his first appearance in court on Monday. Three other officers with him have been fired but for now face no charges.

Governor Tim Walz has mobilized all of Minnesota's National Guard troops  -- the state guard's biggest mobilization ever -- to help restore order.

Police fired tear gas and stun grenades to clear streets of curfew violators Saturday night in Minneapolis.

Walz extended a curfew for a third night Sunday and praised police and guardsmen for holding down violence. "They did so in a professional manner. They did so without a single loss of life and minimal property damage," he said.

"Congratulations to our National Guard for the great job they did immediately upon arriving in Minneapolis, Minnesota, last night," President Donald Trump tweeted, adding that they "should be used in other States before it is too late!"

The Department of Defense said that around 5,000 National Guard troops had been mobilized in 15 states as well as the capital Washington, with another 2,000 on standby.

The widespread resort to uniformed National Guards units is rare, and it evoked disturbing memories of the rioting in US cities in 1967 and 1968 in a turbulent time of protest over racial and economic disparities.

Trump blamed the extreme left for the violence, saying he planned to designate a group known as Antifa as a terrorist organization.

"The violence instigated and carried out by Antifa and other similar groups in connection with the rioting is domestic terrorism and will be treated accordingly," added Attorney General Bill Barr.

'A nation in pain'

Atlanta Mayor Keisha Lance Bottoms said Trump, who has often urged police to use tough tactics, was not helping matters.

"We are beyond a tipping point in this country, and his rhetoric only enflames that," she said on CBS.

Joe Biden, Trump's likely Democratic opponent in November's presidential election, visited the scene of one anti-racism protest.

"We are a nation in pain right now, but we must not allow this pain to destroy us," Biden tweeted, posting a picture of him speaking with an African-American family at the site where protesters had gathered in Delaware late Saturday.

Floyd's death has triggered protests beyond the United States, with hundreds rallying outside the US embassy in London in solidarity.

"I'm here because I'm tired, I'm fed up with it. When does this stop?" Doreen Pierre told AFP at the protest.

In Germany, England football international Jadon Sancho marked one of his three goals for Borussia Dortmund against Paderborn by lifting his jersey to reveal a T-shirt bearing the words "Justice for George Floyd".

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