in

First black hole ever photographed 'appears to be wobbling'

The M87* black hole that was famously photographed by astronomers last year appears to be wobbling, a new study claims.

As it rotates, ‘turbulence’ in the flow of matter being sucked in to the dark central void alters the brightest spot of its surrounding orange ring over time,  giving the illusion that it’s wobbling or ‘glittering’.

M87* resides in the Messier 87 galaxy 54 million light-years away from Earth, in the constellation Virgo. 

It was the subject of the first ever image of a black hole, published in 2019, depicted as a fiery ring of gas and dust around a dark central region – the black hole itself. 

The photo was obtained by a network of eight telescopes at high altitudes around the world,  as part of a project called the Event Horizon Telescope (EHT). 

Scroll down for video 

Snapshots of the M87* black hole obtained through imaging/geometric modelling, and the EHT array of telescopes in 2009 - 2017. The diameter of all rings is similar, but the location of the bright side varies. The variation of the thickness of the ring is most likely not real and results from the limited number of participating observatories in earlier experiments

Snapshots of the M87* black hole obtained through imaging/geometric modelling, and the EHT array of telescopes in 2009 – 2017. The diameter of all rings is similar, but the location of the bright side varies. The variation of the thickness of the ring is most likely not real and results from the limited number of participating observatories in earlier experiments

Now, EHT researchers have analysed previously unpublished data from observations of M87* between 2009 and 2013.

The bright orange ring around the central black void has rotated significantly over the past 10 years of observation, they say. 

While the ring is always present, the brightest part is seen to change its orientation and brightness distribution. 

‘In 2019, we saw the shadow of a black hole for the first time, but we only saw images observed during a one-week window, which is too short to see a lot of changes,’ said study author Maciek Wielgus at Harvard–Smithsonian Center for Astrophysics. 

‘Because the flow of matter falling onto a black hole is turbulent, we can see that the ring wobbles with time.’     

Black holes are unseeable in nature, as no light can escape from them due to their intense gravitational pull. 

However, swirling ultra-hot material forms a ring around the perimeter that reveals the black hole itself. 

The boundary separating this ring of swirling gas and dust from the black hole itself, from which not even light can escape, is called the event horizon. 

Gas falling onto a black hole heats up to billions of degrees, ionizes and becomes turbulent in the presence of magnetic fields. 

This ‘turbulence’ causes the appearance of the black hole to vary over time, the team say.   

‘The data analysis suggests that the orientation and fine structure of the ring varies with time,’ said study author Thomas Krichbaum, astronomer at the Max Planck Institute for Radio Astronomy.

Scientists lifted the veil on the first images ever captured of a black hole's last April. The glowing orange ring shows the event horizon of M87, in the Virgo galaxy cluster

Scientists lifted the veil on the first images ever captured of a black hole’s last April. The glowing orange ring shows the event horizon of M87, in the Virgo galaxy cluster

WHAT IS AN EVENT HORIZON?

The event horizon is theoretical boundary around a black hole where not light or other radiation can escape.

When any of that material gets too close to the edge of the hole, known as the event horizon, its atoms are ripped apart.

The nuclei disappear below the horizon, the much lighter electrons get caught up in the black hole’s intense magnetic field and tosses them around at high speed.

This twisting motion causes them to release photons, which is the main source of emission from matter close to the black hole.

The study gives a first impression on the dynamical structure of the accretion flow – the rate at which material is pulled within it – which affects its appearance.  

‘The accretion flow contains matter than gets close enough to the black hole to allow us to observe the effects of strong gravity,’ Wielgus said.         

The combined data also revealed that M87* adheres to theoretical predictions from general relativity.

The shape of the black hole’s shadow has remained consistent, and its diameter remains in agreement with Einstein’s theory of general relativity for a black hole of such an incredible mass. 

M87* has a mass that’s 6.5 billion times that of our Sun.

‘In this study, we show that the general morphology, or presence of an asymmetric ring, most likely persists on timescales of several years,’ said Kazu Akiyama, a scientist at the MIT Haystack Observatory and a participant on the project. 

‘This is an important confirmation of theoretical expectations as the consistency throughout multiple observational epochs gives us more confidence than ever about the nature of M87* and the origin of the shadow.’            

The analysis has been published in The Astrophysical Journal.  

Developing the technology to capture the image in the first place was a ‘Herculean task’, the researchers said last year, as no single telescope is powerful enough to image a black hole in such detail on its own. 

So, EHT built a ‘virtual telescope’, allowing them to peer into Messier 87.

EHT consists of a network of eight telescopes at high altitudes around the world, in California, Hawaii, Mexico, Arizona, Sierra Nevada, the French Alps, the Chilean Atacama Desert and Antarctica. 

Together they form an Earth-sized virtual telescope with an angular resolution of 20 micro-arcseconds – enough power to read a newspaper in New York from a Paris street.  

The data required more than ‘half a ton of hard drives,’ said Dan Marrone, associate professor of astronomy at the University of Arizona.  

The eight telescopes collected five petabytes of data – or the equivalent of 5,000 years of mp3s, or ‘a lifetime of selfies for 40,000 people’. 

Katie Bouman was instrumental in capturing the very first image of a black hole. Here, she shared her achievement on Facebook

Katie Bouman was instrumental in capturing the very first image of a black hole. Here, she shared her achievement on Facebook

Each telescope produced around 350 terabytes of data per day, which was stored on high-performance helium-filled hard drives and flown to supercomputers in Massachusetts and Bonn, Germany. 

MIT graduate Dr Katie Bouman created an algorithm that collected the data from telescopes to stitch together a photograph of the phenomenon. 

Sharing her achievement on Facebook, Bouman wrote: ‘Watching in disbelief as the first image I ever made of a black hole was in the process of being reconstructed.’ 

The image was named 2019’s most exceptional scientific achievement by the journal Science last December. 

The breakthrough in April 2019 was announced in a series of six papers published in The Astrophysical Journal Letters

BLACK HOLES HAVE A GRAVITATIONAL PULL SO STRONG NOT EVEN LIGHT CAN ESCAPE

Black holes are so dense and their gravitational pull is so strong that no form of radiation can escape them – not even light.

They act as intense sources of gravity which hoover up dust and gas around them. Their intense gravitational pull is thought to be what stars in galaxies orbit around.

How they are formed is still poorly understood. Astronomers believe they may form when a large cloud of gas up to 100,000 times bigger than the sun, collapses into a black hole.

Many of these black hole seeds then merge to form much larger supermassive black holes, which are found at the centre of every known massive galaxy.

Alternatively, a supermassive black hole seed could come from a giant star, about 100 times the sun’s mass, that ultimately forms into a black hole after it runs out of fuel and collapses.

When these giant stars die, they also go ‘supernova’, a huge explosion that expels the matter from the outer layers of the star into deep space. 

Source link

LeBron James’ Lakers and these 3-1 deficits are teaching the young Nuggets a bitter lesson on how to win

Virginia Governor Ralph Northam becomes the third governor to test positive for COVID-19