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.

Comments

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.

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
July 25,2020

In a study conducted in 117 countries, researchers have found that the world is experiencing the most dramatic reduction in the seismic noise (the hum of vibrations in the planet's crust) in recorded history due to global COVID-19 lockdowns.

Measured by instruments called seismometers, seismic noise is caused by vibrations within the Earth, which travel like waves and the waves can be triggered by earthquakes, volcanoes, and bombs - but also by daily human activity like travel and industry.

This quiet period was likely caused by the total global effect of social distancing measures, closure of services and industry, and drops in tourism and travel, the study published in the journal Science, reported.

The new research, led by the Royal Observatory of Belgium and five other institutions around the world including Imperial College London (ICL), showed that the dampening of 'seismic noise' caused by humans was more pronounced in more densely populated areas.

"Our study uniquely highlights just how much human activities impact the solid Earth, and could let us see more clearly than ever what differentiates human and natural noise," said study co-author Stephen Hicks from ICL in the UK.

For the findings, the research team looked at seismic data from a global network of 268 seismic stations in 117 countries and found significant noise reductions compared to before any lockdown at 185 of those stations.

Researchers tracked the 'wave' of quietening between March and May as worldwide lockdown measures took hold.

The largest drops in vibrations were seen in the most densely populated areas, like Singapore and New York City, but drops were also seen in remote areas like Germany's the Black Forest and Rundu in Namibia.

Citizen-owned seismometers, which tend to measure more localised noise, noted large drops around universities and schools around Cornwall, UK and Boston, US - a drop in noise 20 per cent larger than seen during school holidays.

The findings showed that countries like Barbados, where lockdown coincided with the tourist season, saw a 50 per cent decrease in noise.

"The changes have also given us the opportunity to listen in to the Earth's natural vibrations without the distortions of human input," the study authors wrote.

Earlier in April, a study published in the journal Nature, reported at least a 30 per cent reduction in that amount of ambient human noise since lockdown began in Belgium.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
News Network
June 2,2020

London/Milan, Jun 2: World Health Organization experts and a range of other scientists said on Monday there was no evidence to support an assertion by a high profile Italian doctor that the coronavirus causing the COVID-19 pandemic has been losing potency.

Professor Alberto Zangrillo, head of intensive care at Italy's San Raffaele Hospital in Lombardy, which bore the brunt of Italy's COVID-19 epidemic, on Sunday told state television that the new coronavirus "clinically no longer exists".

But WHO epidemiologist Maria Van Kerkhove, as well as several other experts on viruses and infectious diseases, said Zangrillo's comments were not supported by scientific evidence.

There is no data to show the new coronavirus is changing significantly, either in its form of transmission or in the severity of the disease it causes, they said.

"In terms of transmissibility, that has not changed, in terms of severity, that has not changed," Van Kerkhove told reporters.

It is not unusual for viruses to mutate and adapt as they spread, and the debate on Monday highlights how scientists are monitoring and tracking the new virus. The COVID-19 pandemic has so far killed more than 370,000 people and infected more than 6 million.

Martin Hibberd, a professor of emerging infectious disease at the London School of Hygiene & Tropical Medicine, said major studies looking at genetic changes in the SARS-CoV-2 virus that causes COVID-19 did not support the idea that it was becoming less potent, or weakening in any way.

"With data from more than 35,000 whole virus genomes, there is currently no evidence that there is any significant difference relating to severity," he said in an emailed comment.

Zangrillo, well known in Italy as the personal doctor of former Prime Minister Silvio Berlusconi, said his comments were backed up by a study conducted by a fellow scientist, Massimo Clementi, which Zangrillo said would be published next week.

Zangrillo told Reuters: "We have never said that the virus has changed, we said that the interaction between the virus and the host has definitely changed."

He said this could be due either to different characteristics of the virus, which he said they had not yet identified, or different characteristics in those infected.

The study by Clementi, who is director of the microbiology and virology laboratory of San Raffaele, compared virus samples from COVID-19 patients at the Milan-based hospital in March with samples from patients with the disease in May.

"The result was unambiguous: an extremely significant difference between the viral load of patients admitted in March compared to" those admitted last month, Zangrillo said.

Oscar MacLean, an expert at the University of Glasgow's Centre for Virus Research, said suggestions that the virus was weakening were "not supported by anything in the scientific literature and also seem fairly implausible on genetic grounds."

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
News Network
May 15,2020

May 15: Global tensions simmered over the race for a coronavirus vaccine Thursday, as the United States and China traded jabs, and France slammed pharmaceuticals giant Sanofi for suggesting the US would get any eventual vaccine first.

Scientists are working at breakneck speed to develop a vaccine for COVID-19, the disease caused by the virus, which has killed more than 300,000 people worldwide and pummelled economies.

From the US to Europe to Asia, national and local governments are easing lockdown orders to get people back to work -- while fretting over a possible second wave of infections.

Increased freedom of movement means an increased risk of contracting the virus, and so national labs and private firms are labouring to find the right formula for a vaccine.

The European Union's medicines agency offered some hope when it said one could be ready in a year, based on data from clinical trials already underway.

But Marco Cavaleri, the EMA's head of vaccines strategy, acknowledged that timeline was a "best-case scenario," and cautioned that "there may be delays."

The race for a vaccine has exposed a raw nerve in relations between the United States and China, where the virus was first detected late last year in the central city of Wuhan.

Two US agencies warned Wednesday that Chinese hackers were trying to steal COVID-19 vaccine research -- a claim Beijing rejected as "smearing" its reputation.

US President Donald Trump, who has ratcheted up the rhetoric against China, said he doesn't even want to engage with Chinese leader Xi Jinping -- potentially imperilling a trade deal between the world's top two economies.

"I'm very disappointed in China. I will tell you that right now," he said in an interview with Fox Business.

"There are many things we could do. We could do things. We could cut off the whole relationship."

On Capitol Hill, an ousted US health official told Congress that the Trump government had no strategy in place to find and distribute a vaccine to millions of Americans, warning of the "darkest winter" ahead.

"We don't have a single point of leadership right now for this response, and we don't have a master plan," said Rick Bright, who was removed last month as head of the US agency charged with developing a coronavirus vaccine.

The United States has registered nearly 86,000 deaths linked to COVID-19 -- the highest toll of any nation.

World leaders were among 140 signatories to a letter published Thursday saying any vaccine should not be patented and that the science should be shared among nations.

"Governments and international partners must unite around a global guarantee which ensures that, when a safe and effective vaccine is developed, it is produced rapidly at scale and made available for all people, in all countries, free of charge," it said.

But a row erupted in France after drugmaker Sanofi said it would reserve first shipments of any vaccine it discovered to the United States.

The comments prompted a swift rebuke from the French government -- President Emmanuel Macron's office said any vaccine should be treated as "a global public good, which is not submitted to market forces."

Sanofi chief executive Paul Hudson said the US had a risk-sharing model that allowed for manufacturing to start before a vaccine had been finally approved -- while Europe did not.

"The US government has the right to the largest pre-order because it's invested in taking the risk," Hudson told Bloomberg News.

Macron's top officials are scheduled to meet with Sanofi executives about the issue next week.

The search for a vaccine became even more urgent after the World Health Organization said the disease may never go away and the world would have to learn to live with it for good.

"This virus may become just another endemic virus in our communities and this virus may never go away," said Michael Ryan, the UN body's emergencies director.

The prospect of the disease lingering leaves governments facing a delicate balancing act between suppressing the pathogen and getting their economies up and running.

In the US, more grim economic data emerged Thursday, with nearly three million more Americans applying for unemployment benefits.

That takes the overall total to 36.5 million -- more than 10 percent of the US population.

Further signs of the damage to businesses emerged when Lloyd's of London forecast the pandemic will cost the global insurance industry about $203 billion.

European markets closed down, but Wall Street rallied despite the new jobless claims. In a sign of progress, the New York Stock Exchange trading floor was due to reopen on May 26.

The reopening of economies continued in earnest across Europe, where the EU has set out proposals for a phased restart of travel and the eventual lifting of border controls.

"Maybe it's a mistake, but we have no choice. Without tourists, we won't get by!" Enrico Facchetti, a 61-year-old former goldsmith, said of Venice's reopening.

Japan -- the world's third largest economy -- lifted a state of emergency across most of the country except for Tokyo and Osaka.

And Canadian Prime Minister Justin Trudeau said national parks would partially reopen on June 1.

But in Latin America, the virus continued to surge, with a 60 percent leap in cases in the Chilean capital of Santiago.

Authorities said 2,000 new graves were being dug at the main cemetery.

South Sudan reported its first COVID-19 death on Thursday.

And in Bangladesh, the first case was confirmed in the teeming Rohingya refugee camps in Bangladesh, which are home to nearly one million people.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.