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Take a 360 degree tour of the centre of the Milky Way

Budding astronauts can take a virtual space flight to the deepest depths of our galaxy, thanks to a stunning new interactive graphic produced by Nasa.

The immersive 360° visualisation depicts the heart of the Milky Way, roughly 26,000 light years (150,000 trillion miles) away from Earth.

It was created using data taken by satellites, which capture light that has managed to escape the monster black hole that lies in the middle of our spiral galaxy.

 

Powerful winds of gas streaming from the surface of these stars are carrying some of their outer layers into interstellar space. When the outflowing gas collides with emissions from other stars they produce shock waves, similar to sonic booms, which permeate the area 

WHAT THE VISUALISATION SHOWS 

The Galactic Centre visualisation is a 360° movie that immerses a viewer into a simulation of the centre of our galaxy.

The footage shows the complex web of interactions between the supermassive black hole known as Sagittarius A* (Sgr A*) and the surrounding Wolf-Rayet stars.

The viewer is placed at the location of Sgr A* and is able to see about 20 of the giant stellar objects.

These appear as white, twinkling objects, orbiting around the viewer. 

They continuously eject stellar winds, which are shown in a black to red to yellow colour scale.

These winds collide with each other, and then some of this material spirals towards Sgr A*.

The visualisation shows two scenarios, both of which start 350 years in the past and span 500 years.

The first simulation shows Sgr A* in a calm state, while the second contains a more violent Sgr A* that is expelling its own material.

This negates the build up of clumped material, depicted as yellow blobs, that is so prominent in the first portion.

The project, made using data from Nasa’s Chandra X-ray Observatory, lets viewers control their own exploration of the fascinating environment of volatile giant stars and powerful gravity around the huge black hole.

While humans cannot physically travel there, scientists have been able to study this region by using X-ray, infrared and other observation methods.

The visualisation also uses infrared data from the European Southern Observatory’s Very Large Telescope that found 30 massive stellar giants, called Wolf-Rayet stars, which orbit within about 1.5 light years (8.8 trillion miles) of the galactic centre.

Powerful winds of gas streaming from the surface of these stars are carrying some of their outer layers into interstellar space. 

When the outflowing gas collides with emissions from other stars they produce shock waves, similar to sonic booms, which permeate the area.

These shock waves heat the gas to millions of degrees, which causes it to glow in X-ray images. 

Extensive observations with Chandra have provided critical data about the temperature and distribution of this gas.

Astronomers are interested in better understanding what role these Wolf-Rayet stars play in the cosmic neighbourhood at the Milky Way’s centre. 

In particular, they would like to know how the stars interact with the supermassive black hole known as Sagittarius A* (Sgr A*).

Pre-eminent yet invisible, Sgr A* has the mass equivalent to some four million suns. 

In the new visualisation, the viewer is at the location of Sgr A* and is able to see about 20 Wolf-Rayet stars, which appear as white, twinkling objects, orbiting Sgr A* as they continuously eject stellar winds, which are shown in a black to red to yellow colour scale.

These winds collide with each other, and then some of this material spirals towards Sgr A*. 

The footage, which starts 350 years in the past, spans 500 years.

In the new visualisation, the viewer is at the location of SA* and is able to see about 20 Wolf-Rayet stars, which appear as white, twinkling objects, orbiting Sgr A* as they continuously eject stellar winds, which are shown in a black to red to yellow colour scale

In the new visualisation, the viewer is at the location of Sagittarius A*  (Sgr A*) and is able to see about 20 Wolf-Rayet stars, which appear as white, twinkling objects, orbiting Sgr A* as they continuously eject stellar winds, which are shown in a black to red to yellow colour scale

Budding astronauts can take a virtual space flight to the deepest darkest depths of our galaxy, thanks to the stunning new graphic produced by Nasa. The immersive 360° visualisation depicts the centre of the Milky Way, roughly 26,000 light years (150,000 trillion miles) away from Earth

Budding astronauts can take a virtual space flight to the deepest darkest depths of our galaxy, thanks to the stunning new graphic produced by Nasa. The immersive 360° visualisation depicts the centre of the Milky Way, roughly 26,000 light years (150,000 trillion miles) away from Earth

The footage was created using data taken by satellites, which capture light that has managed to escape the monster black hole that lies at the heart of our spiral galaxy

The footage was created using data taken by satellites, which capture light that has managed to escape the monster black hole that lies at the heart of our spiral galaxy

WHAT IS CHANDRA? 

Launched on on July 23, 1999, Nasa’s Chandra X-ray Observatory is a telescope specially designed to detect X-ray emission from very hot regions of the Universe.

This includes exploded stars, clusters of galaxies, and matter around black holes. 

Because X-rays are absorbed by Earth’s atmosphere, Chandra must orbit above it, up to an altitude of 86,500 miles (139,000 km) in space.

The Smithsonian’s Astrophysical Observatory in Cambridge, Massachusetts, hosts the Chandra X-ray Center.

This operates the satellite, processes the data, and distributes it to scientists around the world for analysis. 

The Center maintains an extensive public web site about the science results and an education program.

This visualisation builds on infrared data from the European Southern Observatory¿s Very Large Telescope of 30 massive stellar giants called Wolf-Rayet stars that orbit within about 1.5 light years (8.8 trillion miles) of the centre of our galaxy

This visualisation builds on infrared data from the European Southern Observatory’s Very Large Telescope of 30 massive stellar giants called Wolf-Rayet stars that orbit within about 1.5 light years (8.8 trillion miles) of the centre of our galaxy

As the strong gravity of Sgr A* pulls clumps of material inwards, tidal forces stretch them as they get closer to the black hole.

Sgr A* also impacts its surroundings through occasional outbursts that result in the expulsion of material away from the giant black hole.

These outbursts can have the effect of clearing away some of the gas produced by the Wolf-Rayet winds. 

Evidence of a black hole at the centre of our galaxy was first presented by physicist Karl Jansky in 1931, when he discovered radio waves coming from the region.

If scientists are able to successfully image Sgr A*, the breakthrough would serve as a key test for Einstein’s theory of gravity and could cause us to rewrite our understanding of basic physics.

SAGITTARIUS A AND WOLF-RAYET STARS

Astronomers are interested in better understanding what role Wolf-Rayet stars, stellar giants that orbit within about 1.5 light years (8.8 trillion miles) of the centre of our galaxy, play in the cosmic neighbourhood at the Milky Way’s centre.

In particular, they would like to know how the stars interact with the Galactic centre’s most dominant resident, the supermassive black hole known as Sagittarius A* (Sgr A*). 

Evidence of a black hole at the centre of our galaxy was first presented by physicist Karl Jansky in 1931, when he discovered radio waves coming from the region. 

Pre-eminent yet invisible, Sgr A* has the mass equivalent to some four million suns. 

Scientists have used the new visualisation to examine the effects Sgr A* has on its stellar neighbours. 

Powerful winds of gas streaming from the surface of these Wolf-Rayet stars stars are carrying some of their outer layers into interstellar space. 

When the outflowing gas collides with emissions from other stars they produce shock waves, similar to sonic booms, which permeate the area.

As the strong gravity of Sgr A* pulls clumps of material inwards, tidal forces stretch the clumps as they get closer to the black hole. 

Sgr A* also impacts its surroundings through occasional outbursts from its vicinity that result in the expulsion of material away from the giant black hole. 

These outbursts can have the effect of clearing away some of the gas produced by the Wolf-Rayet winds.  

According to Einstein’s equations, light would be caused by gas and dust accelerating at high speed and being torn apart.

This means the black hole might look like a series of gold rings.

‘As I’ve said before, it’s never a good idea to bet against Einstein, but if we did see something that was very different from what we expect we would have to reassess the theory of gravity’, project leader Sheperd Doeleman from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts told the BBC .

‘I don’t expect that is going to happen, but anything could happen and that’s the beauty of it.’

Researchers, led by Christopher Russell of the Pontifical Catholic University of Chile, used the new visualisation to understand the presence of previously-detected X-rays in the shape of a disk that extend about 0.6 light years (3.5 trillion miles) outward from Sgr A*.

Astronomers are interested in better understanding what role these Wolf-Rayet stars play in the cosmic neighbourhood at the Milky Way¿s centre

Astronomers are interested in better understanding what role these Wolf-Rayet stars play in the cosmic neighbourhood at the Milky Way’s centre

In particular, they would like to know how the stars interact with the Galactic centre's most dominant resident, the supermassive black hole known as Sgr A

In particular, they would like to know how the stars interact with the Galactic centre’s most dominant resident, the supermassive black hole known as Sgr A* (artist’s impression)

The project, made using data from Nasa¿s Chandra X-ray Observatory (artist's impression) and other telescopes, lets viewers control their own exploration of the fascinating environment of volatile giant stars and powerful gravity around the huge black hole

The project, made using data from Nasa’s Chandra X-ray Observatory (artist’s impression) and other telescopes, lets viewers control their own exploration of the fascinating environment of volatile giant stars and powerful gravity around the huge black hole

SUPERMASSIVE BLACK HOLES

Supermassive black holes are incredibly dense areas in the centre of galaxies with masses that can be billions of times that of the sun.

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.

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. 

Their work shows that the amount of X-rays generated by these colliding winds depends on the strength of outbursts powered by Sgr A*, and also the amount of time that has elapsed since an eruption occurred.

Stronger and more recent outbursts result in weaker X-ray emission.

The information provided by the visualisation and the theoretical modelling led Dr Russell and his colleagues to determine that Sgr A* had a relatively powerful outburst that started within the last few centuries. 

Moreover, their findings suggest the outburst from the supermassive black hole is still affecting the region around Sgr A* even though it ended about one hundred years ago. 

The X-ray emission is fainter than predicted by the models, for times when the effects of any past outbursts have completely subsided.



Read more at DailyMail.co.uk


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