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
February 13,2020

New Delhi, Feb 13: Arvind Kejriwal wrote to Delhi Lieutenant Governor Anil Baijal on Wednesday, staking claim to form the government in the national capital, sources said, while hinting that the AAP might not invite senior leaders and chief ministers of other parties for the oath-taking ceremony.

The sources said it was the formal process by the AAP chief, who was elected as the legislature party leader earlier in the day, to stake claim for forming the new government.

Kejriwal, who returned to power in Delhi with a stunning poll victory on Tuesday, will take oath as chief minister for the third consecutive time on February 16.

While the oath-taking ceremony will be open to the public, the Aam Aadmi Party (AAP) was considering not inviting leaders and chief ministers of other parties as it did not wish to be seen as a "confrontationist" against the BJP-led Centre, the sources said.

They, however, added that the party was yet to take a decision on it.

The AAP has planned mobilisation of people for the mega event and all the newly-elected MLAs of the party have been asked to ensure huge participation from their constituencies.

"I request the people of Delhi to attend the oath-taking ceremony of the chief minister at the Ramlila Maidan in large numbers," senior AAP leader Manish Sisodia told reporters, adding that the ceremony will start at 10 am.

The AAP won 62 seats in the 70-member Delhi Assembly, while the Bharatiya Janata Party (BJP) bagged the remaining eight seats. The Congress drew a blank for the second consecutive time in the Delhi polls.

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News Network
February 11,2020

Feb 11: China reported 108 new coronavirus deaths on February 10, the highest daily toll since the outbreak began in Wuhan late last year, as two senior officials in the hard-hit province of Hubei were removed from their jobs.

The total number of deaths on the mainland reached 1,016 in the 24 hours until midnight, the National Health Commission said on Tuesday.

Some 2,478 new cases were confirmed, bringing the total to 42,638.

Of the new deaths, 103 were in the province of Hubei, including 67 in the provincial capital of Wuhan. The virus is thought to have originated there in a market that sold seafood as well as wild animals.

Two senior health officials in the province - Zhang Jin who was Party Secretary of the health commission for Hubei and Ling Yingzi who was director of the Hubei Provincial Health Commission - were both removed from their posts, state media reported on Tuesday,  a day after Chinese President Xi Jinping visited health facilities in Beijing.

In his first public appearance since the outbreak began, Xi donned a face mask and had his temperature checked while visiting medical workers and patients in the capital.

"We have seen very little of Xi Jinping since the outbreak began but he was out and about in Beijing on Monday," Al Jazeera's Katrina Yu said from Beijing. "He has been trying to rally the troops saying: 'We can win this battle.' But it's also a sign that the battle is far from over."

The other fatalities on Monday were in the provinces of Heilongjiang, Anhui and Henan and the cities of Tianjin and Beijing, the National Health Commission said.

During a meeting chaired by Premier Li Keqiang on Monday, a group of leaders tasked with beating the virus said it would work to solve raw material and labour shortages and boost supplies of masks and protective clothing.

They said nearly 20,000 medical personnel from around the country had already been sent to Wuhan, and more medical teams were also on the way.

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News Network
February 18,2020

Beijing, Feb 18: Police in China have arrested a prominent activist who had been a fugitive for weeks and criticised President Xi Jinping's handling of the coronavirus epidemic while in hiding, a rights group said Tuesday.

Anti-corruption activist Xu Zhiyong was arrested on Saturday after being on the run since December, according to Amnesty International.

China's ruling Communist Party has severely curtailed civil liberties since Xi took power in 2012, rounding up rights lawyers, labour activists and even Marxist students.

The death this month of a whistleblowing doctor who was reprimanded by police for raising the alarm about the deadly new virus before dying of it himself triggered rare calls for political reform and freedom of speech.

The "Chinese government's battle against the coronavirus has in no way diverted it from its ongoing general campaign to crush all dissenting voices," said Patrick Poon, China researcher at Amnesty International, in an emailed statement.

Another source, who spoke to news agency on the condition of anonymity, said Xu had been arrested in the southern city of Guangzhou.

Guangzhou police did not respond to requests for comment.

Xu went into hiding after authorities broke up a December gathering of intellectuals discussing political reform in the eastern coastal city of Xiamen in Fujian province, prior to the coronavirus crisis.

Over a dozen lawyers and activists were detained or disappeared after the Xiamen gathering, according to rights groups -- and Xu's detention appears linked to his presence at the meeting, explained Poon.

But while on the run, Xu continued to post information on Twitter about rights issues.

On February 4 Xu released an article calling on Xi to step down and criticised his leadership across a range of issues including the US-China trade war, Hong Kong's pro-democracy protests and the coronavirus epidemic, which has now killed nearly 1,900 people.

"Medical supplies are tight, hospitals are filled with patients, and a large number of infected people have no way to be diagnosed," he wrote. "It's a mess."

"The coronavirus outbreak shows just how important values like freedom of expression and transparency are -- the exact values that Xu has long advocated," Yaqiu Wang, China researcher at Human Rights Watch, told news agency.

But the disappearance of Xu illustrates how the Chinese state "persists in its old ways" by "silencing its critics", she said.

Xu -- who founded a movement calling for greater transparency among high-ranking officials -- previously served a four-year prison sentence from 2013 to 2017 for organising an "illegal gathering".

"That he was a fugitive for so many days while continuing to speak out, that in itself was... a kind of challenge to (Chinese authorities)," said Hua Ze, a long-time friend of Xu who told AFP she lost contact with the Chinese activist on Saturday morning.

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