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Halifax researcher part of team behind black hole discovery that proves Einstein right – Global News

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A researcher at Saint Mary’s University in Halifax was part of a team of scientists that observed light coming from behind a black hole for the very first time, confirming a prediction from famous physicist Albert Einstein’s theory of general relativity.

While scientists have seen X-ray emissions around black holes before, it’s the first time light has been spotted behind a black hole – and the new discovery could lead to a better understanding of what’s still largely considered to be an astronomical mystery.

Luigi Gallo, a professor of astronomy at Saint Mary’s University who’s been studying black holes for 20 years, worked on the data analysis and interpretation for this research project, led by Stanford University astrophysicist Dan Wilkins.

“They’re my favourite objects, but I think I’m biased a bit,” Gallo said of black holes. “It’s the most extreme object in space, right? We don’t know a lot about them.”

Read more:
Nova Scotia professor studies light at the edge of supermassive black holes

Gallo’s research focuses on supermassive black holes – the regions in space where gravity is so strong that not even light can escape. Supermassive black holes are 10 million times larger than the sun.

Because of their very nature, black holes themselves can’t be seen. Scientists are only able to observe the objects around them.

As materials in space fall into a black hole, they form what’s called an “accretion disk,” where they spiral around before falling into the black hole.


The flares echo off of the gas falling into the black hole, and as the flares were subsiding, short flashes of X-rays were seen corresponding to the reflection of the flares from the far side of the disk, bent around the black hole by its strong gravitational field.


ESA/S. Poletti

On top of a black hole is a primary light source known as a “corona,” which illuminates the material. When the light shines onto the accretion disk, it bounces off and creates X-ray emissions or flares.

“It’s not exactly like a reflection in a mirror. What happens is that light comes back with different colours and it comes back at different times,” Gallo explained.

Proving Einstein right

What the five-person research team observed was a big flare coming from a supermassive black hole in a galaxy 800 million light-years away known as I Zwicky 1, using two space-based X-ray telescopes from NASA and the European Space Agency.

Shortly after seeing the big flare, Gallo said they observed a smaller flare in a different colour – an “echo” of the first flare.

“We were able to interpret that as light coming from the other side of the black hole,” said Gallo. “Which is really kind of cool, we haven’t ever been able to isolate exactly where light is coming from on the accretion disk … but in this instance, we’re actually able to say, ‘Oh, this light is coming from behind the black hole.’”


Click to play video: 'Shedding light on a black hole'



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Shedding light on a black hole


Shedding light on a black hole – Mar 26, 2021

That echo could be seen because the black hole was warping space by bending light around itself. Thus, Einstein’s century-old prediction was proven right, Gallo said.

“This is basically confirming how the space-time around a supermassive black hole is shaped,” he said.

“That’s why we can see light coming from behind the black hole, it’s because it’s taken this curved path around the black hole and landing now on us, so that we can see it … Because space is bent, which is a prediction of general relativity, we’re able to see what’s behind the black hole.”

This research, published earlier this week in Nature, opens the door a little further for scientists studying black holes.

Read more:
Astronomers observe collision of 2 black holes — 7 billion years later

Gallo said it will allow them to eventually draw a 3D picture of what the region around the supermassive black hole looks like. As well, he said they will continue to study “coronas” to better understand them, which was actually the driving motivation behind this discovery.

Gallo took note of the “incremental” nature of science and said there are decades of other discoveries that led them to this point.

“The telescopes that we work on get better and better with time, and the techniques that we develop get better and better,” he said.

“The discovery made today … is based on decades of work of many, many other scientists that brought us here.”

Read more:
New ‘black neutron star’ stuns astronomers with its spectacular death

He added that it’s important to study black holes, since their formation and evolution is “tightly linked” to the formation and evolution of galaxies.

“Galaxies are stars, and then the stars are forming planets, and planets are where we are,” he said. “All this is kind of tied in understanding the origins of where we come from.

“So it is an important field of research, but it’s fun. So it’s kind of easy for me to justify doing this kind of work.”

— With a file from The Canadian Press

© 2021 Global News, a division of Corus Entertainment Inc.

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Full moon may hinder most anticipated meteor shower of the year – DiscoverWestman.com

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This weekend is the peak of Perseid’s meteor shower, one of the best-known and largest celestial events that can be seen from Earth.

Throughout the past couple of days, meteors have been visible to on-lookers and will get an even better view during the event’s peak on Friday night.

“Meteors are these tiny little pieces of space dust that crash into the earth and burn up, and when that happens we see them in the sky as a falling star or a shooting star,” says Scott Young, the Planetarium Astronomer at the Manitoba Museum. “The meteor is sort of the official name for those objects, and on any night you can probably see one or two of those if you’re lucky, but on certain nights of the year, the Earth goes through a big cloud of cosmic dust and when you get all that dust hitting the Earth all on the same night, you get lots of meteors. So we call that a meteor shower.”

Young also says that it won’t look as if thousands of stars are falling out of the sky, but rather it will be one star every minute instead of one a night.

“It always occurs every year around August 11-13, somewhere in that range because we’re going through the dust bunny left behind by a comet that crosses Earth’s orbit. Now, that doesn’t always mean that you will see all of those things hitting the Earth, and the timing might happen during the day for you. It might be cloudy, or like this year, close to the full moon. When the full moon is up, it makes it hard to see some of those fainter meteors that you would see.”

The best time to see any meteor shower is between midnight and dawn. According to Young, even with the bright light of the full moon on the same night as the peak time to see meteors, it is a strong enough shower that viewers will still be able to see shooting stars. 

“The official peak occurs after midnight, Friday night, so Saturday morning around 3:00 a.m. our time. But to be honest, it’s not a single-night event. It builds up over a previous couple of weeks and each night there’ll be more and more meteor showers until the peak and then after the peak, it fades away for a couple of weeks.”

The comet that causes the meteor shower is comet Swift–Tuttle, discovered by Lewis Swift and Horace Parnell Tuttle in 1862.

“Each meteor shower over the course of the year has its own source objects, most of them are comets and we know that when we get close to the comet’s orbit in our orbit, we’ll see this meteor shower. They’re actually named after the constellations in the sky where the meteors look like they’re coming from. When we’re looking at the sky, it seems that the meteors from the Perseid meteor shower will come from the constellation Perseus, which is rising in the northeastern part of the sky at this time of year. That doesn’t mean you have to know where Perseus is, the meteors can appear all over the sky.”

To get the best view of the meteor shower peak, Young suggests viewers go to a place where there are not a lot of lights and even “put your back towards any bright lights that are like the moon or city lights.” He also suggests putting the phone away, because the bright light will cause your eyes to need time to adjust to the dark sky and some of the dimmer shooting stars may be missed.

“This is one of those things where you have to unplug, disconnect and just lay out under the stars, relax and look up. it’s a great therapeutic way to connect with the sky.”

Normally on the peak day of the event, Young will go out with an all-sky camera and broadcast live on the Manitoba Museum’s Facebook and YouTube pages, but he says it always depends on the weather.

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Talk like you: Scientists discover why humans evolved to talk while other primates can’t – Euronews

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Why did humans evolve to talk, while monkeys were left to hoot, squeak and grunt to communicate?

The question has long puzzled scientists, who blamed our closest primate cousins’ inability to reproduce human speech sounds on their vocal anatomy.

Until now, researchers could not quite underpin what happened exactly during our evolution to make us able to speak while apes and monkeys can’t, given our vocal structures look almost identical to other primates.

Now, a new study published on Thursday in the journal Science claims to have the answer – and it’s not what anyone expected.

Analysing the phonal apparatus – the larynx – of 43 species of primates, a team of researchers based mainly in Japan found that all non-human primates – from orangutans to chimpanzees – had an additional feature in their throat that humans do not have.

Ability to speak and develop languages

While both humans and non-human primates produce sounds by forcing air through their larynges, causing folds of tissue to vibrate, monkeys and apes have an additional feature, a thin flap of tissue known as vocal membranes, or vocal lips.

Compared to apes and monkeys, humans were found to lack this anatomical vocal membrane – a small muscle just above the vocal cords – as well as balloon-like laryngeal structures called air sacs which apes and monkeys use to produce the loud calls and screams we’re not quite capable of.

According to the researchers, humans have lost this extra vocal tissue over time, somehow simplifying and stabilising the sounds coming out of our throat, and allowing us, in time, to develop the ability to speak – and eventually develop very complex sophisticated languages.

Monkeys and apes, on the other hand, maintained these vocal lips which don’t really allow them to control the inflection and register of their voice and produce stable, clear vocal fold vibrations.

“Paradoxically, the increased complexity of human spoken language thus followed simplification of our laryngeal anatomy,” says the study.

Communication through sign language

It’s unclear when humans lost these extra tissues still present in apes and monkeys and became able to speak, as the soft tissues in the larynx are not preserved in fossils, and researchers could only study living species.

We know that it must have happened sometime after the Homo Sapiens lineage split from the other primates, some 6-7 million years ago.

The fact that apes and monkeys haven’t developed the ability to speak like humans doesn’t mean that they are not able to clearly communicate with each other.

Though their vocal anatomy doesn’t allow them to form vowel sounds and proper words, non-human primates have a complex communication system based primarily on body language rather than oral sounds.

But monkeys and apes have also proven to be able to communicate with humans.

In the not-often-happy history of the interaction between non-human primates and humans, researchers have been able to teach apes and monkeys to communicate with people.

Koko the gorilla, for example, became famous for being able to use over 1,000 hand signs in sign language, while the bonobo Kanzi was reportedly able to communicate using a keyboard.

But when it comes to having a chat, monkeys and humans might never be able to share one.

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When Summer 'Supermoons' Hit Your Eye: Spectacular Photos – Forbes

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When the moon takes the celestial stage during the summer, the spectacle is simply amazing: Currently topping the program is the Sturgeon Supermoon, shining in all its splendor.

In July, it was the Buck Supermoon, the biggest and shiniest of the year. That one followed the Strawberry Supermoon that delighted sky watchers in June.

They have other stage names. This Sturgeon Moon, which derives its principal name from the giant sturgeon fish season in the Great Lakes, is known also as Thunder Moon, Mead Moon and Hay Moon, among others, and is the last supermoon of the year.

July’s Buck Moon, which drew that name because the antlers of male deer — bucks — are in full-growth mode at the time, is also called Salmon Moon and Berry Moon.

The Strawberry supermoon of June gets its name from fruit harvest seasons. It’s also known as Blooming Moon, Honey Moon and the Mead Moon.

The full moon names collected by the iconic Old Farmer’s Almanac come mainly from Native American tribes, Colonial American, and European sources.

“A full moon doubles as a supermoon when it’s near perigee, or the point in the moon’s orbit that is closest to Earth,” the Almanac explains, making it larger and brighter.

August’s Sturgeon Moon is the fourth and final supermoon of the year and it happens to coincide with the Perseid meteor shower, considered by many as “the best meteor shower of the year,” according to NASA. It will peak on August 13 and will remain active through August 24.

And if you happen to notice a bright-looking “star” near the moon, you’re looking at Saturn.

Lunar lovers and star seekers have been enjoying the summer’s stunning celestial performances and here are some of the best photos taken around the globe:

July’s Buck Supermoon

June’s Strawberry Supermoon of June

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