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 5,2020

May 5: Global coronavirus deaths reached 250,000 on Monday after recorded infections topped 3.5 million, a news agency tally of official government data showed, although the rate of fatalities has slowed.

North America and European countries accounted for most of the new deaths and cases reported in recent days, but numbers were rising from smaller bases in Latin America, Africa and Russia.

Globally, there were 3,062 new deaths and 61,923 new cases over the past 24 hours, taking total cases to 3.58 million.

That easily exceeds the estimated 140,000 deaths worldwide in 2018 caused by measles, and compares with around 3 million to 5 million cases of severe illness caused annually by seasonal influenza, according to the World Health Organization (WHO).

While the current trajectory of COVID-19 falls far short of the 1918 Spanish flu, which infected an estimated 500 million people, killing at least 10% of patients, experts worry the available data is underplaying the true impact of the pandemic.

The concerns come as several countries begin to ease strict lockdowns that have been credited with helping contain the spread of the virus.

"We could easily have a second or a third wave because a lot of places aren't immune," Peter Collignon, an infectious diseases physician and microbiologist at Canberra Hospital, told Reuters. He noted the world was well short of herd immunity, which requires around 60% of the population to have recovered from the disease.

The first death linked to COVID-19 was reported on Jan. 10 in Wuhan, China after the coronavirus first emerged there in December. Global fatalities grew at a rate of 1-2% in recent days, down from 14% on March 21, according to the Reuters data.

DEATH RATE ANOMALIES

Mortality rates from recorded infections vary greatly from country to country.

Collignon said any country with a mortality rate of more than 2% almost certainly had underreported case numbers. Health experts fear those ratios could worsen in regions and countries less prepared to deal with the health crisis.

"If your mortality rate is higher than 2%, you've missed a lot of cases," he said, noting that countries overwhelmed by the outbreak were less likely to conduct testing in the community and record deaths outside of hospitals.

In the United States, around half the country's state governors partially reopened their economies over the weekend, while others, including New York Governor Andrew Cuomo, declared the move was premature.

In Britain, Prime Minister Boris Johnson, who battled COVID-19 last month, has said the country was over the peak but it was still too early to relax lockdown measures.

Even in countries where the suppression of the disease has been considered successful, such as Australia and New Zealand which have recorded low daily rates of new infections for weeks, officials have been cautious.

Australian Prime Minister Scott Morrison has predicated a full lifting of curbs on widespread public adoption of a mobile phone tracking app and increased testing levels.

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Agencies
March 29,2020

A shrimp seller at the wet market in the Chinese city of Wuhan believed to be the centre of the coronavirus pandemic, may be the first person to have tested positive for the disease, a media report said on Saturday.

The report by the London-based Metro newspaper said that 57-year-old woman, named by the Wall Street Journal as Wei Guixian, was selling shrimp at the Huanan Seafood Market when she developed what she thought was a cold last December.

Chinese digital news outlet, The Paper has said that she may be epatient zero'.

Wei was told by doctors her illness was "ruthless" and other workers at the market had come to the Wuhan Union Hospital with the same symptoms, the Metro newspaper report quoted the outlet as saying.

"Every winter, I suffer from the flu, so I thought it was the flu," the woman was quoted as saying by The Paper news outlet.

The shrimp seller added that she believed she contracted the coronavirus from the shared toilet in the market.

She said the fatal disease would have killed fewer people if the government had acted sooner.

Wuhan Municipal Health Commission has confirmed that Wei was among the first 27 people to test positive for the coronavirus.

It said she was one of 24 cases with direct links to the market, the Metro newspaper reported.

Though Wei may be "patient zero", it does not mean she is the first person to have contracted the virus, added the Metro report.

Chinese researchers have claimed that the first person diagnosed with the airborne virus had no contact with the seafood market and was identified on December 1, 2019.

Wei was later quarantined when a connection was made between the bug and the market before recovering in January.

As of Saturday, the global number of coronavirus cases stood at 104,837 with 27,862 deaths, according to the latest update by the Washington-based Johns Hopkins University.

The US has the highest number of cases at 104,837, followed by Italy 86,498 and China 81,948.

Italy has recorded the highest number of fatalities with 9,134 deaths, followed by Spain and China, at 5,138 and 3,299, respectively.

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News Network
July 10,2020

Lahore, Jul 10: The Punjab government enforced smart lockdown in seven cities of the province for 15 days with an immediate effect from Thursday night, The News International reported.

The Primary and Secondary Healthcare Department on Thursday issued a notification under the Punjab Infectious Diseases Ordinance 2020, about enforcement of lockdown in Lahore, Multan, Faisalabad, Gujranwala, Sialkot, Gujrat and Rawalpindi, till July 24 midnight.

In Lahore, the lockdown will be enforced in A2 Block Township, EME Society, Main Bazaar Chungi Amr Sadhu, Punjab Government Servants Housing Scheme, Wapda Town, C-Block Jauhar Town and Green City.

The basic necessities of life will remain available in smart lockdown areas. "The purpose of the smart lockdown is to minimise movement of people in hotspots of positive coronavirus cases," said Capt (retd) Muhammad Usman, Secretary, Primary and Secondary Healthcare Department.

The country registered 2,751 new COVID-19 cases during the last 24 hours, taking the tally to 243,599 on Friday. The province-wise breakup includes 85,261 cases in Punjab, 100,900 cases in Sindh, 29,406 in Khyber Pakhtunkhwa, 11,099 in Balochistan, 13,829 in Islamabad, 1,619 in Gilgit-Baltistan and 1,485 in Pakistan-occupied Kashmir.

The death toll due to the virus reached 5,058 with 75 more deaths reported over the last 24 hours, as per data cited by Radio Pakistan.

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