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 23,2020

Jun 23: US President Donald Trump has issued a proclamation to suspend issuing of H-1B visas, which is popular among Indian IT professionals, along with other foreign work visas for the rest of the year.

Trump said the step was essential to help millions of Americans who have lost their jobs due to the current economic crisis.

Issuing the proclamation ahead of the November presidential elections, Trump has ignored the mounting opposition to the order by various business organisations, lawmakers and human rights bodies.

The proclamation that comes into effect on June 24, is expected to impact a large number of Indian IT professionals and several American and Indian companies who were issued H-1B visas by the US government for the fiscal year 2021 beginning October 1.

They would now have to wait at least till the end of the current year before approaching the US diplomatic missions to get stamping. It would also impact a large number of Indian IT professionals who are seeking renewal of their H-1B visas.

“In the administration of our Nation's immigration system, we must remain mindful of the impact of foreign workers on the United States labour market, particularly in the current extraordinary environment of high domestic unemployment and depressed demand for labour,” said the proclamation issued by Trump.

In his proclamation, Trump said that the overall unemployment rate in the United States nearly quadrupled between February and May of 2020 -- producing some of the most extreme unemployment rates ever recorded by the Bureau of Labor Statistics.

While the May rate of 13.3 percent reflects a marked decline from April, millions of Americans remain out of work.

The proclamation also extends till the end of the year his previous executive order that had banned issuing of new green cards of lawful permanent residency.

Green card holders, once admitted pursuant to immigrant visas, are granted "open-market" employment authorisation documents, allowing them immediate eligibility to compete for almost any job, in any sector of the economy, he said.

“American workers compete against foreign nationals for jobs in every sector of our economy, including against millions of aliens who enter the United States to perform temporary work. Temporary workers are often accompanied by their spouses and children, many of whom also compete against American workers,” Trump said.

“Under ordinary circumstances, properly administered temporary worker programmes can provide benefits to the economy. But under the extraordinary circumstances of the economic contraction resulting from the COVID-19 outbreak, certain non-immigrant visa programmes authorising such employment pose an unusual threat to the employment of American workers,” he said.

For example, Trump said, between February and April of 2020, more than 17 million United States jobs were lost in industries in which employers are seeking to fill worker positions tied to H-2B nonimmigrant visas.

“During this same period, more than 20 million United States workers lost their jobs in key industries where employers are currently requesting H-1B and L workers to fill positions,” he said.

“Also, the May unemployment rate for young Americans, who compete with certain J non-immigrant visa applicants, has been particularly high -- 29.9 percent for 16-19-year-olds, and 23.2 percent for the 20-24-year-old group,” he said.

“The entry of additional workers through the H-1B, H-2B, J, and L non-immigrant visa programmes, therefore, presents a significant threat to employment opportunities for Americans affected by the extraordinary economic disruptions caused by the COVID-19 outbreak,” Trump said.

Trump observed that excess labour supply is particularly harmful to workers at the margin between employment and unemployment -- those who are typically "last in" during an economic expansion and "first out" during an economic contraction.

In recent years, these workers have been disproportionately represented by historically disadvantaged groups, including African Americans and other minorities, those without a college degree, and Americans with disabilities, he said.

The proclamation suspends and limits entry into the US of H-1B, H-2B and L visas and their dependents till December 31, 2020. It also includes certain categories of J visas like an intern, trainee, teacher, camp counselor, or summer work travel programme.

The new rule would apply only to those who are outside the US, do not have a valid non-immigrant visa and an official travel document other than a visa to enter the country.

According to the proclamation, it does not have an impact on lawful permanent residents of the United States and foreign nationals who are spouses or child of an American citizen.

Foreign nationals seeking to enter the US to provide temporary labour or services essential to the food supply chain are also exempted from the latest proclamation.

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News Network
June 18,2020

Washington, Jun 18: US Defence officials are concerned over China's use of COVID-19 situation to gain stakes in strategically important companies of United States as the impact of novel coronavirus has left several companies in dire need of capital.

Amid the pandemic, it getting hard for the defence department to keep an eye on national security and help protect smaller companies down the chain, CNN reported.

"We are paying close attention to any indicators that China is leveraging Covid-19 to take advantage of a situation where defence companies need capital more than ever," a defence official told CNN.

In April, Ellen Lord, undersecretary of defence for acquisition and sustainment said it is paying close attention to 'adversaries' against the 'economic warfare' with the United States.

"We have to be very, very careful about the focused efforts some of our adversaries have to really undergo sort of economic warfare with us, which has been going on for some time," Ellen Lord, undersecretary of defence for acquisition and sustainment was quoted as saying by CNN.

US Committee on Foreign Investment protects its interest against hostile countries gaining ownership in strategically important companies. But the pandemic is changing the definition of national security concerns to include drugs, protective gear and medical supplies.

"These are now national security needs and we probably should have been thinking about it a long time ago in terms of biowarfare that we should have a trusted industrial base or a set of trusted allies -- the UK, or NATO allies or Japan or Korea -- who are trusted in that regard," Bill Greenwalt, a former Pentagon official.

Give the threat posed by foreign acquisition, Pentagon has been offering tools to help small US businesses defend themselves against adversarial investment and conducting background checks with other government agencies to ensure transparency.

US President Donald Trump's trade adviser Peter Navarro recently told CNN if Trump wins reelection, Washington DC will likely take offshore supply chains as national security priorities.

"If we fail to do that in the face of this crisis, we will have failed this country and all future generations of Americans," Navarro said.

The US State Department has also warned US allies to "avoid economic overreliance on China" and "guard their critical infrastructure" from China's influence.

Chad P Bown, a senior fellow at the Peterson Institute for International Economics, pointed to recent China's economic coercion of Australia on the political matter saying, "this is how China operates and everybody knows it."

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News Network
May 28,2020

Geneva, May 28: The global death toll from the novel coronavirus has risen over the past 24 hours by 5,581 to 349,095, the World Health Organization (WHO) said in its daily situation report.

The number of confirmed cases has increased by 84,314 to 5,488,825, the WHO said.

Most cases of infection are recorded in the Americas (North and South America) - 2,495,924, with 145,810 deaths. While Europe has reported 2,061,828 cases and 1,76,226 deaths so far.

As per WHO tally, the US has the highest number of cases in the world with 1,63,4010 infections.

The global health body declared the outbreak of the new coronavirus a pandemic on March 11.

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