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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News Network
July 5,2020

Washington, Jul 5: US President Donald Trump on Saturday thanked Prime Minister Narendra Modi for his wishes on America's 244th Independence Day.

On Saturday, PM Modi tweeted: "I congratulate @POTUS @realDonaldTrump and the people of the USA on the 244th Independence Day of the USA. As the world's largest democracies, we cherish freedom and human enterprise that this day celebrates. @WhiteHouse"

While replying to PM Modi's wishes, Mr Trump tweeted: "Thank you my friend. America loves India!"

The US President also attended the July 4 American Independence Day celebrations in South Dakota.

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Agencies
July 7,2020

Washington, Jul 7: The US military "will continue to stand strong” in relationship to a conflict between India and China or anywhere else, a top White House official said on Monday, after the navy deployed two aircraft carriers to the South China Sea to boost its presence in the region.

"The message is clear. We're not going to stand by and let China or anyone else take the reins in terms of being the most powerful, dominant force, whether it's in that region or over here,” White House Chief of Staff Mark Meadows told Fox News.

“And the message is clear. Our military might stands strong and will continue to stand strong, whether it's in relationship to a conflict between India and China or anywhere else,” Meadows said in response to a question.

He was told that India banned Chinese apps because Indian soldiers were killed by Chinese troops last month and asked what's mission of the two aircraft carriers - the Ronald Reagan and the Nimitz - and what's America's mission.

The troops of India and China are locked in an eight-week standoff in several areas in eastern Ladakh including Pangong Tso, Galwan Valley and Gogra Hot Spring. The situation deteriorated last month following the Galwan Valley clashes that left 20 Indian Army personnel dead as the two sides significantly bolstered their deployments in most areas along the LAC.

The Chinese military on Monday began withdrawing troops from the Galwan Valley and Gogra Hot Spring after National Security Advisor Ajit Doval and Chinese Foreign Minister Wang Yi held lengthy talks on Sunday. Doval and Wang are also the special representatives on the India-China boundary talks.

The United States has sent two of its aircraft carriers to the South China Sea. “Our mission is to make sure that the world knows that we still have the preeminent fighting force on the face of the globe,” Meadows said.

President Donald Trump has invested more in the US military, more in not only the hardware, but the men and women who serve so sacrificially each and every day, he said. “He (Trump) continues to do so,” he added.

China is engaged in hotly contested territorial disputes in both the South China Sea and the East China Sea. Beijing has built up and militarised many of the islands and reefs it controls in the region. Both areas are stated to be rich in minerals, oil and other natural resources and are vital to global trade.

China claims almost all of the South China Sea. Vietnam, the Philippines, Malaysia, Brunei and Taiwan have counter claims over the area.

Appearing on the same Fox News on Monday talk show with host Brian Kilmeade, influential Republican Senator Tom Cotton said that the US aircraft carriers are headed to the South China Sea to thwart off any Chinese misadventure against Taiwan or other countries in the region.

"That's one of the reasons why we have those aircraft carrier groups in the South China Sea. I mean, look what China did in the southwest. It's essentially invaded India over the last few weeks and killed Indian soldiers,” Cotton said.

"No country on China's periphery, right now, is safe from Chinese aggression. All those countries want a close relationship with the United States. We ought to have one,” Cotton said.

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Agencies
August 7,2020

Russia boasts that it's about to become the first country to approve a Covid-19 vaccine, with mass vaccinations planned as early as October using shots that are yet to complete clinical trials -- and scientists worldwide are sounding the alarm that the headlong rush could backfire.

Moscow sees a Sputnik-like propaganda victory, recalling the Soviet Union's launch of the world's first satellite in 1957.

But the experimental Covid-19 shots began first-in-human testing on a few dozen people less than two months ago, and there's no published scientific evidence yet backing Russia's late entry to the global vaccine race, much less explaining why it should be considered a front-runner.

“I'm worried that Russia is cutting corners so that the vaccine that will come out may be not just ineffective, but also unsafe,” said Lawrence Gostin, a global public health law expert at Georgetown University. “It doesn't work that way... Trials come first. That's really important.”

According to Kirill Dmitriev, head of Russia's Direct Investment Fund that bankrolled the effort, a vaccine developed by the Gamaleya research institute in Moscow may be approved in days, before scientists complete what's called a Phase 3 study.

That final-stage study, usually involving tens of thousands of people, is the only way to prove if an experimental vaccine is safe and really works.

Health Minister Mikhail Murashko said members of “risk groups,” such as medical workers, may be offered the vaccine this month.

He didn't clarify whether they would be part of the Phase 3 study that is said to be completed after the vaccine receives “conditional approval.”

Deputy Prime Minister Tatyana Golikova promised to start “industrial production” in September, and Murashko said mass vaccination may begin as early as October.

Dr Anthony Fauci, the top US infectious disease specialist, questioned the fast-track approach last week.

“I do hope that the Chinese and the Russians are actually testing a vaccine before they are administering the vaccine to anyone, because claims of having a vaccine ready to distribute before you do testing I think is problematic at best," he said.

Questions about this vaccine candidate come after the US, Britain and Canada last month accused Russia of using hackers to steal vaccine research from Western labs.

Delivering a vaccine first is a matter of national prestige for the Kremlin as it tries to assert the image of Russia as a global power capable of competing with the US and China.

The notion of being “the first in the world” dominated state news coverage of the effort, with government officials praising reports of the first-step testing.

In April, President Vladimir Putin ordered state officials to shorten the time of clinical trials for a variety of drugs, including potential coronavirus vaccines.

According to Russia's Association of Clinical Trials Organizations, the order set “an unattainable bar” for scientists who, as a result, "joined in on the mad race, hoping to please those at power.”

The association first raised concern in late May, when professor Alexander Gintsburg, head of the Gamaleya institute, said he and other researchers tried the vaccine on themselves.

The move was a “crude violation of the very foundations of clinical research, Russian law and universally accepted international regulations" the group said in an open letter to the government, urging scientists and health officials to adhere to clinical research standards.

But a month later, the Health Ministry authorized clinical trials of the Gamaleya product, with what appeared to be another ethical issue.

Human studies started June 17 among 76 volunteers. Half were injected with a vaccine in liquid form and the other half with a vaccine that came as soluble powder.

Some in the first half were recruited from the military, which raised concerns that servicemen may have been pressured to participate.

Some experts said their desire to perform well would affect the findings. “It's no coincidence media reports we see about the trials among the military said no one had any side effects, while the (other group) reported some," said Vasily Vlassov, a public health expert with Moscow's Higher School of Economics.

As the trials were declared completed and looming regulatory approval was announced last week, questions arose about the vaccine's safety and effectiveness.

Government assurances the drug produced the desired immune response and caused no significant side effects were hardly convincing without published scientific data describing the findings.

The World Health Organization said all vaccine candidates should go through full stages of testing before being rolled out.

“There are established practices and there are guidelines out,” WHO spokesman Christian Lindmeier said Tuesday.

“Between finding or having a clue of maybe having a vaccine that works, and having gone through all the stages, is a big difference.”

Offering an unsafe compound to medical workers on the front lines of the outbreak could make things worse, Georgetown's Gostin said, adding: “What if the vaccine started killing them or making them very ill?”

Vaccines that are not properly tested can cause harm in many ways — from a negative impact on health to creating a false sense of security or undermining trust in vaccinations, said Thomas Bollyky, director of the global health program at the Council on Foreign Relations. 

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