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
June 16,2020

Beijing, Jun 16: The coronavirus situation in China's capital is "extremely severe", a city official warned Tuesday, as 27 new infections were reported from Beijing where a new cluster has sparked a huge trace-and-test programme.

The COVID-19 resurgence -- believed to have started at the sprawling Xinfadi wholesale food market in the capital -- has sparked alarm as China had largely brought its outbreak under control through mass testing and lockdowns imposed earlier in the year.

The new cases took the number of confirmed infections in Beijing over the past five days to 106, as authorities locked down almost 30 communities in the city and tested tens of thousands of people.

"The epidemic situation in the capital is extremely severe," Beijing city spokesman Xu Hejian warned at a press conference.

The World Health Organization had already expressed concern about the cluster, pointing to Beijing's size and connectivity.

Officials in the capital have said they will test stall owners and managers at all of the city's food markets, restaurants and government canteens.

Beijing's coronavirus testing capacity has been expanded to 90,000 a day, according to China's official news agency Xinhua.

On Tuesday, the capital's transport commission banned taxi- and ride-hailing services from driving out of the city, Xinhua reported, in another move to try and contain the new outbreak.

All indoor sports and entertainment venues in Beijing were ordered to shut on Monday, and some other cities across China warned they would quarantine those arriving from the capital.

The National Health Commission also reported four new domestic infections in Hebei province, which surrounds Beijing, and a case reported in southwestern Sichuan province was linked to the Beijing cluster.

Authorities were also racing to track people from Beijing who had travelled to other parts of China, and those who visited the capital have been encouraged to get tested.

Beijing spokesman Xu said: "High-risk people who have left Beijing must inform local authorities immediately."

Market inspections

Authorities shut down another market on Tuesday -- Tiantaohonglian in the central Xicheng district -- after one employee there was diagnosed with COVID-19, state broadcaster CCTV reported.

Seven residential estates surrounding that market were also locked down.

In total, Beijing officials said Tuesday they have disinfected 276 agricultural markets, closed 11 markets, and disinfected more than 33,000 food and beverage businesses in a bid to stamp out the new cluster.

Officials had warned Sunday that since May 30, 200,000 people had visited the Xinfadi market -- the original site of the new outbreak.

More than 8,000 workers from Xinfadi have been tested and sent to centralised quarantine facilities.

Until this recent outbreak, most of China's cases in recent months were nationals returning home as the pandemic spread to other countries.

China's Center for Disease Control and Prevention said Monday that the virus strain found in the Beijing outbreak was a "major epidemic strain in the European countries".

While the virus was detected on chopping boards used to handle imported salmon at Xinfadi, "it does not clearly or definitely indicate it's from imported seafood", Wu Zunyou, the body's chief epidemiologist, said in an interview with state broadcaster CCTV.

"Ever since new cases suddenly emerged in Beijing, we have tried to figure out the reasons for the outbreak since there were no COVID-19 cases found over the past two months," Wu Zunyou said.

"We came up with several possibilities, and the most likely one is that the carrier of the novel coronavirus comes from outside China or other parts of China and brought it here."

On Tuesday, another eight imported cases were reported.

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News Network
February 28,2020

Washington, Feb 28: US intelligence agencies are monitoring the global spread of coronavirus and the ability of governments to respond, sources familiar with the matter said on Thursday, warning that there were concerns about how India would cope with a widespread outbreak.

While there are only a few known cases in India, one source said the country's available countermeasures and the potential for the virus to spread given India's dense population was a focus of serious concern.

US intelligence agencies are also focusing on Iran, where the country's deputy health minister has fallen ill during a worsening outbreak.

US Secretary of State Mike Pompeo said on Tuesday the United States was "deeply concerned" Tehran may have covered up details about the spread of coronavirus. A US government source said Iran's response was considered ineffective because the government only has minimal capabilities to respond to the outbreak.

Another source said US agencies were also concerned about the weak ability of governments in some developing countries to respond to an outbreak.

The US House of Representatives Intelligence Committee has received a briefing on the virus from the spy agencies. "The Committee has received a briefing from the IC (intelligence community) on coronavirus, and continues to receive updates on the outbreak on a daily basis," an official of the House Intelligence Committee told Reuters.

"Addressing the threat has both national security and economic dimensions, requiring a concerted government-wide effort and the IC is playing an important role in monitoring the spread of the outbreak, and the worldwide response," the official added.

A source familiar with the activities of the Senate Intelligence Committee, led by Republican Senator Richard Burr and Democratic Senator Mark Warner, said the panel was receiving daily updates. The role of US intelligence agencies in responding to the coronavirus epidemic at this point principally involves monitoring the spread of the illness around the world and assessing the responses of governments.

They are working closely with health agencies, such as the US Center for Disease Control, in sharing information they collect and targeting further intelligence gathering.

One source said US agencies would use a wide range of intelligence tools, ranging from undercover informants to electronic eavesdropping tools, to track the virus' impact.

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News Network
July 1,2020

Tehran, Jul 1 As many as 19 people have been killed in an explosion and fire at a medical facility in Tehran.

A total of 19 people, including 15 men and 4 women, were killed in the explosion, the emergency services confirmed, RT reported citing KhabarOnline website.

According to a regional official, a gas leak caused the incident. Sputnik quoted a deputy head of Tehran police as saying to YJC news outlet that oxygen tanks exploded in the semi-basement of the clinic.

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