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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News Network
May 30,2020

Washington, May 30: President Donald Trump said Friday he would strip several of Hong Kong's special privileges with the United States and bar some Chinese students from US universities in anger over Beijing's bid to exert control in the financial hub.

In a day of concerted action, the United States and Britain also raised alarm at the UN Security Council over a controversial new security law for Hong Kong, angering Beijing which said the issue had no place at the world body.

In a White House appearance that Trump had teased for a day, the US president attacked China over its treatment of the former British colony, saying it was "diminishing the city's longstanding and proud status."

"This is a tragedy for the people of Hong Kong, the people of China and indeed the people of the world," Trump said.

Trump also said he was terminating the US relationship with the World Health Organization, which he has accused of pro-China bias in its management of the coronavirus crisis.

But Trump was light on specifics and notably avoided personal criticism of President Xi Jinping, with whom he has boasted of having a friendship even as the two powers feud over a rising range of issues.

"I am directing my administration to begin the process of eliminating policy that gives Hong Kong different and special treatment," Trump said.

"This will affect the full range of agreements, from our extradition treaty to our export controls on dual-use technologies and more, with few exceptions," he said.

Secretary of State Mike Pompeo on Wednesday informed Congress that the Trump administration would no longer consider Hong Kong to be separate under US law, but it was up to Trump to spell out the consequences.

China this week pressed ahead on a law that would ban subversion and other perceived offenses against its rule in Hong Kong, which was rocked by months of massive pro-democracy protests last year.

US restricts students

In one move that could have long-reaching consequences, Trump issued an order to ban graduate students from US universities who are connected to China's military.

"For years, the government of China has conducted elicit espionage to steal our industrial secrets, of which there are many," Trump said.

Hawkish Republicans have been clamoring to kick out Chinese students enrolled in sensitive fields. The FBI in February said it was investigating 1,000 cases of Chinese economic espionage and technological theft.

But any move to deter students is unwelcome for US universities, which rely increasingly on tuition from foreigners and have already been hit hard by the COVID-19 shutdown.

China has been the top source of foreign students to the United States for the past decade with nearly 370,000 Chinese at US universities, although Trump's order will not directly affect undergraduates.

Critics say Trump has been eager to fan outrage about China to deflect attention from his own handling of the coronavirus pandemic that has killed more than 100,000 people in the United States, the highest number of deaths of any country.

Chuck Schumer, the top Democrat in the Senate, called Trump's announcement "just pathetic."

Eliot Engel, a Democrat who heads the House Foreign Affairs Committee, noted that Trump treaded lightly on Hong Kong during last year's protests as he sought a trade deal with Xi.

"Now, the president wants to shift the blame for his failures onto China, so he's doing the right thing for the wrong reason," Engel said.

Trump's order could also trigger retaliation. China in March expelled US journalists after the Trump administration tightened visa rules for staff at Chinese state media.

Clash at UN

The United States and Britain earlier in the day urged China to reconsider the Hong Kong law during talks at the UN Security Council, where China wields a veto -- making any formal session, let alone action against Beijing, impossible.

The Western allies raised Hong Kong in an informal, closed-door videoconference where China cannot block the agenda.

They said China was violating an international commitment as the 1984 handover agreement with Britain, in which Beijing promised to maintain the financial hub's separate system until at least 2047, was registered with the United Nations.

"The United States is resolute, and calls upon all UN members states to join us in demanding that the PRC immediately reverse course and honor its international legal commitments to this institution and to the Hong Kong people," said US Ambassador Kelly Craft, referring to the People's Republic of China.  

China demanded that the United States and Britain "immediately stop interfering in Hong Kong affairs," saying the law did not fall under the Security Council's mandate.

"Any attempt to use Hong Kong to interfere in China's internal matters is doomed to fail," warned a statement from China's UN mission.

"There was no consensus, no formal discussion in the Security Council, and the US and the UK's move came to nothing," it said.

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News Network
July 11,2020

Geneva, Jul 11: The World Health Organization said Friday that it is still possible to bring coronavirus outbreaks under control, even though case numbers have more than doubled in the past six weeks.

WHO chief Tedros Adhanom Ghebreyesus said the examples of Italy, Spain, South Korea and India's biggest slum showed that however bad a outbreak was, the virus could still be reined in through aggressive action.

"In the last six weeks cases have more than doubled," Tedros told a virtual press conference in Geneva.

However, "there are many examples from around the world that have shown that even if the outbreak is very intense, it can still be brought back under control," said Tedros.

"And some of these examples are Italy, Spain and South Korea, and even in Dharavi -- a densely packed area in the megacity of Mumbai -- a strong focus on community engagement and the basics of testing, tracing, isolating and treating all those that are sick is key to breaking the chains of transmission and suppressing the virus."

The novel coronavirus has killed at least 555,000 people worldwide since the outbreak emerged in China last December, according to a tally from official sources compiled by AFP on Friday.

Nearly 12.3 million cases have been registered in 196 countries and territories.

"Across all walks of life, we are all being tested to the limit," Tedros said, "from countries where there is exponential growth, to places that are loosening restrictions and now starting to see cases rise.

"Only aggressive action combined with national unity and global solidarity can turn this pandemic around."

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News Network
June 27,2020

LGeneva, Jun 27:: The number of confirmed coronavirus cases worldwide has risen by over 177,000 in the past 24 hours to 9.4 million and the death toll has topped 480,000, the World Health Organisation (WHO) said on Friday (local time).

On Thursday, the WHO reported 167,056 new cases and 5,336 related deaths.

The fresh daily situation report estimates the number of infections confirmed in the past 24 hours at 177,012. Further, 5,116 virus-related deaths were reported over the same period, taking the toll to 484,249.

The Americas lead the count with over 4.7 million cases, followed by Europe with more than 2.6 million.

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