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
May 20,2020

Kensington (United States), May 20: The world cut its daily carbon dioxide emissions by 17% at the peak of the pandemic shutdown last month, a new study found.

But with life and heat-trapping gas levels inching back toward normal, the brief pollution break will likely be “a drop in the ocean" when it comes to climate change, scientists said.

In their study of carbon dioxide emissions during the coronavirus pandemic, an international team of scientists calculated that pollution levels are heading back up — and for the year will end up between 4% and 7% lower than 2019 levels.

That's still the biggest annual drop in carbon emissions since World War II.

It'll be 7% if the strictest lockdown rules remain all year long across much of the globe, 4% if they are lifted soon.

For a week in April, the United States cut its carbon dioxide levels by about one-third.

China, the world's biggest emitter of heat-trapping gases, sliced its carbon pollution by nearly a quarter in February, according to a study Tuesday in the journal Nature Climate Change. India and Europe cut emissions by 26% and 27% respectively.

The biggest global drop was from April 4 through 9 when the world was spewing 18.7 million tons (17 million metric tons) of carbon pollution a day less than it was doing on New Year's Day.

Such low global emission levels haven't been recorded since 2006. But if the world returns to its slowly increasing pollution levels next year, the temporary reduction amounts to ''a drop in the ocean," said study lead author Corinne LeQuere, a climate scientist at the University of East Anglia.

“It's like you have a bath filled with water and you're turning off the tap for 10 seconds," she said.

By April 30, the world carbon pollution levels had grown by 3.3 million tons (3 million metric tons) a day from its low point earlier in the month. Carbon dioxide stays in the air for about a century.

Outside experts praised the study as the most comprehensive yet, saying it shows how much effort is needed to prevent dangerous levels of further global warming.

“That underscores a simple truth: Individual behavior alone ... won't get us there,” Pennsylvania State University climate scientist Michael Mann, who wasn't part of the study, said in an email.

“We need fundamental structural change.”

If the world could keep up annual emission cuts like this without a pandemic for a couple decades, there's a decent chance Earth can avoid warming another 1.8 degrees (1 degree Celsius) of warming from now, study authors said. But getting the type of yearly cuts to reach that international goal is unlikely, they said.

If next year returns to 2019 pollution levels, it means the world has only bought about a year's delay in hitting the extra 1.8 degrees (1 degree Celsius) of warming that leaders are trying to avoid, LeQuere said. That level could still occur anywhere from 2050 to 2070, the authors said.

The study was carried out by Global Carbon Project, a consortium of international scientists that produces the authoritative annual estimate of carbon dioxide emissions. They looked at 450 databases showing daily energy use and introduced a measurement scale for pandemic-related societal “confinement” in its estimates.

Nearly half the emission reductions came from less transportation pollution, mostly involving cars and trucks, the authors said. By contrast, the study found that drastic reductions in air travel only accounted for 10% of the overall pollution drop.

In the US, the biggest pollution declines were seen in California and Washington with plunges of more than 40%.

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News Network
June 19,2020

London, Jun 19: Malala Yousafzai, the youngest Nobel Peace Prize winner who once took a bullet for campaigning for girls' education in Pakistan, was over the moon on Friday after completing her degree in Philosophy, Politics and Economics at Britain's prestigious Oxford University.

Malala, 22, who attended Oxford's Lady Margaret Hall college, took to Twitter to share two pictures that show her celebrating the milestone with her family.

"Hard to express my joy and gratitude right now as I completed my Philosophy, Politics and Economics degree at Oxford," she said in the tweet, accompanied by two pictures - one showing her sitting with her family in front of a cake that says: 'Happy Graduation Malala', and the other in which she is covered with cake smiling for the camera.

In the tweet, the famed human rights activist also revealed her plans for the immediate future - Netflix, reading and sleeping.

"I don't know what's ahead. For now, it will be Netflix, reading and sleep," she wrote.

Malala was shot in the head by the Taliban militants in December 2012 for campaigning for female education in the Swat Valley in northeastern Pakistan.

Severely wounded, she was airlifted from one military hospital in Pakistan to another and later flown to the UK for treatment.

After the attack, the Taliban released a statement saying that they would target Malala again if she survived.

At the age of 17, Malala became the youngest recipient of the Nobel Peace Prize for her education advocacy in 2014 when she shared the coveted honour with India's social activist Kailash Satyarthi.

Unable to return to Pakistan after her recovery, she moved to Britain, setting up the Malala Fund and supporting local education advocacy groups with a focus on Pakistan, Nigeria, Jordan, Syria and Kenya.

The Taliban, who are against girls' education, have destroyed many schools in Pakistan.

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April 6,2020

Tokyo, April 6: Japan Prime Minister Shinzo Abe is planning to declare a state of emergency in view of the surging cases of coronavirus in the country, especially in Tokyo and other large cities, government sources said on Monday.

Pressure had been mounting on Abe to make the declaration amid a spurt in COVID-19 cases recently, with calls for the move from Tokyo Governor Yuriko Koike and the Japan Medical Association intensifying, Xinhua news agency reported.

The Tokyo metropolitan government, along with healthcare specialists, said that the number of hospital beds available for coronavirus patients will soon reach capacity, with the health ministry rapidly trying to secure more beds.

Adding to pressure on the government to demonstrably bolster its preventive and countermeasures to the spread of the virus, a panel of government experts warned recently that the country's healthcare system could collapse if coronavirus cases continue to spike.

The healthcare system in Tokyo and four other prefectures are under increased strain and "drastic countermeasures need to be taken as quickly as possible," the experts said.

As of Sunday, 143 new cases of COVID-19 were recorded in Tokyo, a record daily high for the capital, bringing the total to 1,034, with Japan's health ministry and local governments adding that nationwide cases rose to 3,531 as of Sunday afternoon.

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