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Dancing gargantuan black holes perform on cue – BBC News

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Dancing gargantuan black holes perform on cue – BBC News

Astronomers have been able to test key consequences of Einstein’s theories by studying the way a couple of black holes move around each other.

One of these objects is a true colossus – a hole weighing 18 billion times the mass of our Sun; the other not quite so big at “only” 150 million Sun masses.

Scientists managed to predict their interactions very precisely.

They did so by including their warping effects on space-time and by assuming the larger hole had a smooth “surface”.

The black hole pairing, known as OJ 287, exists about 3.5 billion light-years from Earth.

Scientists have long recognised a sudden brightening from this system that occurs twice every 12 years. The outburst of energy is equivalent to a trillion suns turning on at once in the holes’ host galaxy.

The best explanation for this extraordinary behaviour is that the smaller object is routinely crashing through a disc of gas and dust that’s accreting on to its larger companion, heating the inspiraling material to extremely high temperatures in the process.

But this flaring is somewhat irregular. Sometimes the brightening episodes in the 12-year period occur as little as one year apart; other times, as much as 10 years apart.

This animation shows how the smaller black hole in OJ 287 orbits its bigger partner

It speaks to the complexity of the path the small hole takes around its partner – a complexity the research team has now built into a highly sophisticated model.

“The orbit of the smaller black hole precesses. That’s why the times of the impacts vary,” explained Prof Mauri Valtonen from the University of Turku, Finland. “Already back in 1996, we had a model that predicted more or less what would happen. But we’ve just got more and more accurate,” he told BBC News.

One of the updated model’s important parameters is the energy radiating away from the system in the form of gravitational waves. These ripples in the fabric of space-time – a consequence of Einstein’s theory of general relativity – are generated by accelerating bodies, and in the super-massive circumstances of OJ 287 they have a significant influence on the way the system operates.

The big test of the latest model came on 31 July last year when the appearance of the most recent flaring was identified to within 2.5 hours of what the equations had anticipated.

Artwork: Spitzer
Image copyright

NASA

The event was captured by the US space agency
Nasa’s Spitzer infrared telescope
, a fortunate observation, as it turned out, because OJ 287 was on the far side of the Sun to the Earth at the time and therefore out of sight to ground-based facilities.

Spitzer’s separation from Earth (160 million km), on the other hand, put it in prime position.

“When I first checked the visibility of OJ 287, I was shocked to find that it became visible to Spitzer right on the day when the next flare was predicted to occur,” said Dr Seppo Laine, a Caltech, US, staff scientist who oversaw the Spitzer viewing.

“It was extremely fortunate that we would be able to capture the peak of this flare with Spitzer, because no other human-made instruments were capable of achieving this feat at that specific point in time.”

Another refinement in the model involved folding in details about the larger black hole’s physical characteristics. Specifically, its rotation.

Scientists, including the late Stephen Hawking, developed what became known as the “no-hair” theorem of black holes. This essentially states that the surface, or “event horizon”, of a black hole along its rotation axis is symmetrical – there are no lumps and bumps.

The observation of OJ 287 is said to be the best test yet of this no-hair idea. If there were serious irregularities, the predicted timing would not have worked out so well.

Prof Achamveedu Gopakumar, from the Tata Institute of Fundamental Research, India, worked on gravitational-wave additions to the model along with graduate student Lankeswar Dey.

The professor spoke of his “elation” on seeing the Spitzer data come through. He is now looking forward to OJ 287 being imaged by the Event Horizon Telescope which produced the first ever picture of a black hole last year.

“The EHT observed the source both in 2017 and 2018. The other campaigns are suspended (because of coronavirus) and we hope to get time during the 2021 campaign,” he told BBC News.

Details of the Spitzer observations are published
in The Astrophysical Journal Letters
.

The next flaring will be in 2022, and then in 2033 and 2034.

Jonathan.Amos-INTERNET@bbc.co.uk
and follow me
on Twitter
.


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Take two for SpaceX's 1st astronaut launch with more storms – CP24 Toronto's Breaking News

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CAPE CANAVERAL, Fla. – SpaceX pressed ahead with its second attempt to launch astronauts for NASA – a historic first for a private company – but more stormy weather threatened more delays.

Elon Musk’s company came within 17 minutes Wednesday of launching a pair of NASA astronauts for the first time in nearly a decade from the U.S., before the threat of lightning forced a delay.

NASA Administrator Jim Bridenstine said managers were debating whether to bump the next launch attempt from Saturday to Sunday to take advantage of a slightly improved forecast at Kennedy Space Center.

At an outdoor news conference Friday, Bridenstine stressed the need for safety for astronauts Doug Hurley and Bob Behnken – no matter how many times it takes to launch them in a SpaceX Dragon capsule atop a SpaceX Falcon 9 rocket to the International Space Station.

“We cannot forget this is a test flight. This – is – a – test – flight,” he repeated. “We will go when everything is as safe as we can possibly make it.”

Forecasters put the odds of acceptable weather conditions Saturday at 50-50, with the outlook improving to 60% favourable on Sunday. Rain and clouds were the main concerns for both days.

Hurley and Behnken, veterans of two space shuttle flights, said they’ve both faced launch delays before. In a tweet Friday, Hurley said his first shuttle flight was scrubbed five times for weather and technical issues.

“We’re ready for the next launch opportunity!” Behnken tweeted.

While NASA urged spectators to stay home Wednesday because of the pandemic, prime viewing spots at area parks and beaches were packed. A weekend launch could draw even bigger crowds. The Kennedy Space Center Visitor Complex reopened Thursday, after a 2 1/2-month shutdown, and within a few hours, all 4,000 tickets were snapped up for Saturday’s launch attempt.

President Donald Trump and Vice-President Mike Pence were expected to return Saturday to watch from inside Kennedy. The number of employees, journalists and guests allowed inside the space centre remained extremely limited because of the pandemic.

Whether an attempt is made Saturday or Sunday, “There will be no pressure. We will launch when we’re ready,” Bridenstine said.

The last time astronauts launched to orbit from the U.S. was in 2011 when Atlantis closed out the 30-year space shuttle program. Hurley was on that mission as well.

NASA hired SpaceX and Boeing in 2014 to get the ball rolling again – kicking off a commercial revolution for getting people to low-Earth orbit, according to officials. In the meantime, NASA has spent billions of dollars to buy seats on Russian Soyuz capsules for U.S. astronauts, in order to keep the space station staffed.

Boeing’s first astronaut flight, on the company’s Starliner capsule, is not expected until next year.

Bridenstine offered high praise for Musk on Friday and all his personal touches: spiffy spacesuits, Tesla rides to the launch pad, a colour-co-ordinated rocket and capsule – and more.

Musk has brought “vision and inspiration” to the American space program, Bridenstine said. While there’s occasionally a little tension between NASA and SpaceX, “he gives me a commitment and he delivers on that commitment. That has happened every single time.”

The California-based SpaceX is also developing a rocket and spaceship designed to go to the moon and Mars.

On Friday, a prototype of its Starship exploded while undergoing a routine engine test at the company’s Texas site. The ship vented large amount of gases and was engulfed in a tremendous fireball.

SpaceX did not respond immediately to a request for comment.

NASA, which has a contract with SpaceX to develop Starship for its lunar landing program, has no problems going ahead with this weekend’s unrelated launch of astronauts from Cape Canaveral, agency spokesman Bob Jacobs.

“That’s a test program. That’s why they test,” Jacobs said.

AP Science Writer Seth Borenstein in Kensington, Maryland, contributed to this report.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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COVID-19: Fanshawe team studies possible way to stop virus's spread in body – London Free Press (Blogs)

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Fanshawe College researchers in London are studying a process that could lead to an effective treatment for COVID-19.

“When a virus enters the body, its ability to produce devastating effects is due to its capacity to make copies of itself while evading the body’s immune system,” said Abdulla Mahboob, manager of Fanshawe’s Centre for Applied Research and Innovation in Biotechnology (CARIB) labs, where the study is underway.

The college team is testing a custom inhibitor they hope will block virus proteins from binding together to help the virus’s genetic material get past cell defences, he said. “If we stop the proteins from binding together, we can expose the virus to the cell’s immunity, which in turn will stop the spread of the virus itself in the patient.”

Scientists are testing the inhibitor using mammalian cells containing the specific proteins targeted in the study, with promising results, the college said.

If effective, the inhibitors would then be tested on the virus in lab-grown cells and work would begin to turn it into a viable treatment for the respiratory disease.

It’s the latest in a number of studies by college scientists, including one looking at the potential benefits of cannabis extract in treating blood clots and inflammation in life-threatening COVID-19 cases.

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Take 2 for SpaceX's first astronaut launch with more storms – CTV News

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CAPE CANAVERAL, FLA. —
SpaceX pressed ahead with its second attempt to launch astronauts for NASA — a historic first for a private company — but more stormy weather threatened more delays.

Elon Musk’s company came within 17 minutes Wednesday of launching a pair of NASA astronauts for the first time in nearly a decade from the U.S., before the threat of lightning forced a delay.

NASA Administrator Jim Bridenstine said managers were debating whether to bump the next launch attempt from Saturday to Sunday to take advantage of a slightly improved forecast at Kennedy Space Center.

At an outdoor news conference Friday, Bridenstine stressed the need for safety for astronauts Doug Hurley and Bob Behnken — no matter how many times it takes to launch them in a SpaceX Dragon capsule atop a SpaceX Falcon 9 rocket to the International Space Station.

“We cannot forget this is a test flight. This — is — a — test — flight,” he repeated. “We will go when everything is as safe as we can possibly make it.”

Forecasters put the odds of acceptable weather conditions Saturday at 50-50, with the outlook improving to 60% favourable on Sunday. Rain and clouds were the main concerns for both days.

While NASA urged spectators to stay home because of the pandemic, prime viewing spots at area parks and beaches were packed Wednesday. A weekend launch could draw even bigger crowds. The Kennedy Space Center Visitor Complex reopened Thursday, after a 2 1/2-month shutdown, and within a few hours, all 4,000 tickets were snapped up for Saturday’s launch attempt.

President Donald Trump and Vice-President Mike Pence were expected to return for the Saturday attempt. The number of employees, journalists and guests inside remained extremely limited because of the pandemic.

Whether an attempt is made Saturday or Sunday, “There will be no pressure. We will launch when we’re ready,” Bridenstine said.

The last time astronauts launched to orbit from the U.S. was in 2011 when Atlantis closed out the 30-year space shuttle program. Hurley was on that mission as well.

NASA hired SpaceX and Boeing in 2014 to get the ball rolling again — kicking off a commercial revolution for getting people to low-Earth orbit, according to officials. In the meantime, NASA has spent billions of dollars to buy seats on Russian Soyuz capsules for U.S. astronauts, in order to keep the space station staffed.

Boeing’s first astronaut flight, on the company’s Starliner capsule, is not expected until next year.

Bridenstine offered high praise for Musk on Friday and all his personal touches: spiffy spacesuits, Tesla rides to the launch pad, a colour-co-ordinated rocket and capsule — and more.

Musk has brought “vision and inspiration” to the American space program, Bridenstine said. While there’s occasionally a little tension between NASA and SpaceX, “he gives me a commitment and he delivers on that commitment. That has happened every single time.”

——

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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