Astronomers discover 83 supermassive black holes 13 billion light-years away

Agencies
March 15, 2019

Washington, Mar 15: Astronomers have discovered 83 quasars powered by supermassive black holes 13 billion light-years away from the Earth, from a time when the universe was less than 10 per cent of its present age.

“It is remarkable that such massive dense objects were able to form so soon after the Big Bang,” said Michael Strauss, a professor at Princeton University in the US.

“Understanding how black holes can form in the early universe, and just how common they are, is a challenge for our cosmological models,” Strauss said in a statement.

This finding, published in The Astrophysical Journal, increases the number of black holes known at that epoch  considerably, and reveals, for the first time, how common they are early in the universe’s history.

In addition, it provides new insight into the effect of black holes on the physical state of gas in the early universe in its first billion years.

Supermassive black holes, found at the centers of galaxies, can be millions or even billions of times more massive than the Sun.

While they are prevalent today, it is unclear when they first formed, and how many existed in the distant early universe.

A supermassive black hole becomes visible when gas accretes onto it, causing it to shine as a “quasar.” Previous studies have been sensitive only to the very rare, most luminous quasars, and thus the most massive black holes.

The new discoveries probe the population of fainter quasars, powered by black holes with masses comparable to most black holes seen in the present-day universe.

The team used data taken with “Hyper Suprime-Cam” (HSC) instrument, mounted on the Subaru Telescope of the National Astronomical Observatory of Japan, which is located on the summit of Maunakea in Hawaii.

The researchers selected distant quasar candidates from the sensitive HSC survey data.

They then carried out an intensive observational campaign to obtain spectra of those candidates, using three telescopes: the Subaru Telescope; the Gran Telescopio Canarias on the island of La Palma in the Canaries, Spain; and the Gemini South Telescope in Chile.

The survey revealed 83 previously unknown very distant quasars.

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ABDUL AZIZ SHE…
 - 
Saturday, 16 Mar 2019

SUBHAANALLAH

 

 
ALLAH ALMIGHTY CREATED EVERTHING  INCLUDING WHOLE UNIVERSE AND WHAT IS IN IT,

HUMAN BEING CANNOT REACH TO UNDERSTAND IT,  HUMAN LIFE NOT SUFFEICENT TO REACH AND KNOW EVERYTHING.

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coastaldigest.com news network
May 6,2020

Mangaluru, May 6: Three more coronavirus positive cases have been reported in Dakshina Kannada district. 

According to fresh bulletin of health and family welfare department, an 11-year-old girl and a 36-year-old woman from Boloor in Mangaluru and a 16-year-old girl from Bantwal tested positive for the covid-19. 

All of them are undergoing treatment at Wenlock Hospital. Their condition is said to be stable. 

With this the total number of cases in the district reached 28 including 22 residents of Dakshina Kannada, 4 from Kasaragod, 1 from Udupi and 1 from Uttara Kannada.

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News Network
May 27,2020

Washington, May 27: Most viruses and other germs do not spread easily on flights, the US Center for Disease Control and Prevention has said in its COVID-19 guidelines which do not recommend following social distancing between two passengers inside a plane or keeping the middle seat unoccupied.

As a result of coronavirus pandemic, air traffic inside the US has come to a near halt. Air traffic is said to be down to about 90 per cent. For all travellers coming from overseas, the Center for Disease Control and Prevention (CDC) has recommended 14 days quarantine.

"Most viruses and other germs do not spread easily on flights because of how air circulates and is filtered on aeroplanes," the CDC has said in its set of COVID-19 guidelines for air travellers.

However, it noted that the air travellers were not risk-free especially in the time of the coronavirus pandemic and recommended Americans to avoid travel as far as possible.

"Air travel requires spending time in security lines and airport terminals, which can bring you in close contact with other people and frequently touched surfaces," it said.

"Social distancing is difficult on crowded flights, and you may have to sit near others (within six feet), sometimes for hours. This may increase your risk for exposure to the virus that causes COVID-19," the CDC said.

But instead of recommended social distancing inside commercial planes, the CDC has advised a series of preventive and hygienic measures to be taken by the airlines pilot and crew to prevent the spread of coronavirus.

The US Department of Transportation and Federal Aviation Administration in its latest safety alerts for operators on May 11 said that air carriers and crews conducting flight operations having a nexus to the US, including both domestic and foreign air carriers, should follow CDC's occupational health and safety guidance.

The CDC issued its guidelines in first guidelines for the airlines and airline crew on March and again in May.

The CDC, which has issued an exhaustive social guideline measures in various sections, is silent on keeping the middle seat of a plane unoccupied so as to maintain the six feet distance between two passengers.

It calls for the plane crew to report to the CDC a traveller with specific COVID-19 symptoms like fever, persistent cough, difficulty in breathing and appearing unwell.

Asking the airlines and cabin crew to review infection control guidelines for cabin crew, the CDC recommends several measures for cabin crew to protect themselves and others, manage a sick traveller, clean contaminated areas, and take actions after a flight.

Prominent among them include washing hands often with soap and water for at least 20 seconds, particularly after assisting sick travellers or touching potentially contaminated body fluids or surfaces and use of alcohol-based hand sanitizer (containing at least 60 per cent alcohol) if soap and water are not available.

Airlines should consider providing alcohol-based hand sanitizer to cabin and flight crews for their personal use, it said.

The CDC guidelines do not recommend following social distancing inside a plane between two passengers or keeping the middle seat unoccupied. But it asks to minimise contact between passengers and cabin crew and the sick person.

"If possible, separate the sick person from others (by a distance of 2 meters or 6 feet, ideally) and designate one crew member to serve the sick person. Offer a facemask, if available and if the sick person can tolerate it. If a facemask is not available or cannot be tolerated, ask the sick person to cover their mouth and nose with tissues when coughing or sneezing," said the CDC guidelines.

If no symptomatic passengers were identified during or immediately after the flight, the CDC recommends airlines to follow routine operating procedures for cleaning aircraft, managing solid waste, and wearing PPE.

"If symptomatic passengers are identified during or immediately after the flight, routine cleaning procedures should be followed, and enhanced cleaning procedures should also be used," it said.

Clean porous (soft) surfaces (e.g, cloth seats, cloth seat belts) at the seat of the symptomatic passengers and within 6 feet of the symptomatic passengers in all directions, it added.

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News Network
March 5,2020

Washington, Feb 5: Experts warned a US government panel last night that India's Muslims face risks of expulsion and persecution under the country’s new Citizenship Amendment Act (CAA) which has triggered major protests.

The hearing held inside Congress was called by the US Commission on International Freedom, which has been denounced by the Indian government as biased.

Ashutosh Varshney, a prominent scholar of sectarian violence in India, told the panel that the law championed by prime minister Narendra Modi's government amounted to a move to narrow the democracy's historically inclusive and secular definition of citizenship.

"The threat is serious, and the implications quite horrendous," said Varshney, a professor at Brown University.

"Something deeply injurious to the Muslim minority can happen once their citizenship rights are taken away," he said.

Varshney warned that the law could ultimately lead to expulsion or detention -- but, even if not, contributes to marginalization.

"It creates an enabling atmosphere for violence once you say that a particular community is not fully Indian or its Indianness in grave doubt," he said.

India's parliament in December passed a law that fast-tracks citizenship for persecuted non-Muslim minorities from neighboring countries.

Responding to criticism at the time from the US commission, which advises but does not set policy, India's External Affairs Ministry said the law does not strip anyone's citizenship and "should be welcomed, not criticized, by those who are genuinely committed to religious freedom."

Fears are particularly acute in Assam, where a citizens' register finalized last year left 1.9 million people, many of them Muslims, facing possible statelessness.

Aman Wadud, a human rights lawyer from Assam who traveled to Washington for the hearing, said that many Indians lacked birth certificates or other documentation to prove citizenship and were only seeking "a dignified life."

The hearing did not exclusively focus on India, with commissioners and witnesses voicing grave concern over Myanmar's refusal to grant citizenship to the Rohingya, the mostly Muslim minority that has faced widespread violence.

Gayle Manchin, the vice chair of the commission, also voiced concern over Bahrain's stripping of citizenship from activists of the Shiite majority as well as a new digital ID system in Kenya that she said risks excluding minorities.

More than 40 people were killed last week in New Delhi in sectarian violence sparked by the citizenship law.

India on Tuesday lodged another protest after the UN human rights chief, Michele Bachelet, sought to join a lawsuit in India that challenges the citizenship law's constitutionality.

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