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
July 15,2020

Washington, Jul 15: The Trump administration has agreed to rescind its July 6 rule, which temporarily barred international students from staying in the United States unless they attend at least one in-person course, a federal district court judge said on Tuesday.

The U-turn by the Trump administration comes following a nationwide outrage against its July 6 order and a series of lawsuits filed by a large number of educational institutions, led by the prestigious Harvard University and Massachusetts Institute of Technology (MIT), seeking a permanent injunctive relief to bar the Department of Homeland Security (DHS) and the US Immigration and Customs Enforcement (ICE) from enforcing the federal guidelines barring international students attending colleges and universities offering only online courses from staying in the country.

As many as 17 US states and the District of Columbia, along with top American IT companies such as Google, Facebook and Microsoft, joined MIT and Harvard in the US District Court in Massachusetts against the DHS and the ICE in seeking an injunction to stop the entire rule from going into effect.

"I have been informed by the parties that they have come to a resolution. They will return to the status quo," Judge Allison Burroughs, the federal district judge in Boston, said in a surprise statement at the top of the hearing on the lawsuit.

The announcement comes as a big relief to international students, including those from India. In the 2018-2019 academic year, there were over 10 lakh international students in the US. According to a recent report of the Student and Exchange Visitor Program (SEVP), 1,94,556 Indian students were enrolled in various academic institutions in the US in January.

Judge Burroughs said the policy would apply nationwide.

"Both the policy directive and the frequently asked questions would not be enforced anyplace," she said, referring to the agreement between the US government and MIT and Harvard.

Congressman Brad Scneider said this is a great win for international students, colleges and common sense.

"The Administration needs to give us a plan to tackle our public health crisis - it can't be recklessly creating rules one day and rescinding them the next," he said in a tweet.

Last week, more than 136 Congressmen and 30 senators wrote to the Trump administration to rescind its order on international students.

"This is a major victory for the students, organisers and institutions of higher education in the #MA7 and all across the country that stood up and fought back against this racist and xenophobic rule," said Congresswoman Ayanna Pressley.

"Taking online classes shouldn't force international students out of our country," Congressman Mikie Sherrill said in a tweet.

In its July 6 notice, the ICE had said all student visa holders, whose university curricula were only offered online, "must depart the country or take other measures, such as transferring to a school with in-person instruction to remain in lawful status".

"If not, they may face immigration consequences, including but not limited to the initiation of removal proceedings," it had said.

In their lawsuit, the 17 states and the District of Columbia said for many international students, remote learning in the countries and communities they come from would impede their studies or be simply impossible.

The lawsuit alleged that the new rule imposes a significant economic harm by precluding thousands of international students from coming to and residing in the US and finding employment in fields such as science, technology, biotechnology, healthcare, business and finance, and education, and contributing to the overall economy.

In a separate filing, companies like Google, Facebook and Microsoft, along with the US Chamber of Commerce and other IT advocacy groups, asserted that the July 6 ICE directive will disrupt their recruiting plans, making it impossible to bring on board international students that businesses, including the amici, had planned to hire, and disturb the recruiting process on which the firms have relied on to identify and train their future employees.

The July 6 directive will make it impossible for a large number of international students to participate in the CPT and OPT programmes. The US will "nonsensically be sending...these graduates away to work for our global competitors and compete against us...instead of capitalising on the investment in their education here in the US", they said.

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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
June 11,2020

Jun 11: The total death toll in the US from the novel coronavirus pandemic could hit the grim figure of 200,000 by September and expecting a dramatic decrease in COVID-19 cases in the country will be a "wishful thinking , an eminent Indian-American professor has warned.

Ashish Jha, the head of Harvard's Global Health Institute, told CNN on Wednesday that he is not trying to scare people to stay at home rather urged everyone to wear masks, adhere to the social distancing rules and called for ramping up testing and tracing infrastructure.

Anybody who's expecting a dramatic decrease in cases is almost surely engaging in wishful thinking. And if it (COVID numbers) stays just flat for the next three months, we're going to hit 200,000 deaths sometime in September and that is just awful, Jha said.

Jha said the 200,000 death toll is not just a guess . Currently 800-1000 people are dying daily in America from the virus and all data suggest that the situation is going to get worse.

We're gonna have increases, but even if we assume that it's going to be flat all summer, that nothing is going to get worse... even if we pick that low number of 800 a day, that is 25,000 (deaths) a month in three and a half months. We're going to add another 88,000 people and we will hit 200,000 sometime in September, Jha said.

The United States is by far the hardest-hit country in the global pandemic, in terms of both confirmed infections and deaths.

According to data by the Johns Hopkins University, the number of coronavirus cases in the US currently is nearly two million and about 112,900 people have died in the country, the most in the world.

When asked about an improvement in states like New York, which had been the epicenter of the COVID19 pandemic in the US, Jha said while coronavirus cases are declining in New York, New Jersey, Connecticut and Massachusetts, the numbers are increasing in states such as Arizona, Florida, Texas, North and South Carolina while the country as a whole is pretty flat.

He said, people should take measures as that will help suppress the virus and ensure people could get back outside safely but he voiced concern that this was not the situation in reality.

We're not doing that and so we're going to unfortunately have another 25,000 deaths a month until September, and then it'll keep going. It's not going to magically disappear. We've got a turn around. This is not the future I want, he said.

Jha said he had expected the situation to improve in the summer months but on the contrary the numbers have continued to rise even in the warm weather.

Summer was supposed to be our better months - warmer weather, people outside, a little less transmission. This is not the time (summer) I was expecting a lot more cases. We're seeing a lot more cases, especially in states like Arizona where the numbers look really scary, he said.

Jha added that he was hopeful that maybe the summer months would give us more of a break. I think I may have been too optimistic on that.

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