•   
  •   

Tech & Science Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way

13:31  20 january  2020
13:31  20 january  2020 Source:   sciencealert.com

Young stars at the edge of the Milky Way appear to have come from 2 nearby galaxies. That means a galactic collision could happen sooner than predicted.

  Young stars at the edge of the Milky Way appear to have come from 2 nearby galaxies. That means a galactic collision could happen sooner than predicted. Astronomers discovered a cluster of thousands of young stars appearing in the most ancient reaches of the Milky Way. The new stars seem to come from two nearby galaxies, the Large and Small Magellanic Clouds, which are on track to crash into our galaxy in 2 or 3 billion years. The discovery indicates that this galactic collision could happen sooner than scientists expected. Visit Business Insider's homepage for more stories. A future galactic collision is already causing new stars to form at the edge of the Milky Way, astronomers say. The farthest reaches of our galaxy contain its oldest stars.

Theres something really weird in the centre of the Milky Way . The vicinity of a supermassive black hole is a pretty weird place to start with, but astronomers have found Ghez and her colleagues have been studying the galactic centre for over 20 years. Now, based on that data, a team of astronomers

Three supermassive black holes found at center of unusual, smashed galaxy . Huge, spiral galaxies like our home galaxy -- the Milky Way -- look like beautiful, starry pinwheels, but not all galaxies are formed with such artistic sensibilities.

  Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way © Jack Ciurlo/UCLA

There's something really weird in the centre of the Milky Way.

The vicinity of a supermassive black hole is a pretty weird place to start with, but astronomers have found six objects orbiting Sagittarius A* that are unlike anything in the galaxy. They are so peculiar that they have been assigned a brand-new class - what astronomers are calling G objects.

The original two objects - named G1 and G2 - first caught the eye of astronomers nearly two decades ago, with their orbits and odd natures gradually pieced together over subsequent years. They seemed to be giant gas clouds 100 astronomical units across, stretching out longer when they got close to the black hole, with gas and dust emission spectra.

New Observations From Hubble Could Confirm a Leading Theory on Dark Matter

  New Observations From Hubble Could Confirm a Leading Theory on Dark Matter A new technique using the Hubble Space Telescope and a feature of general relativity has revealed the smallest clumps of dark matter ever identified - up to 100,000 times less massive than the Milky Way galaxy's dark matter halo. And these (relatively) teeny tiny clumps of dark matter nicely agree with one of the leading dark matter theories - what astronomers call cold dark matter. "We made a very compelling observational test for the cold dark matter model and it passes with flying colours," said astrophysicist Tommaso Treu of the University of California, Los Angeles.We don't actually know what dark matter is. We can't directly detect it.

Strange Objects called G objects found at The Milkyway Galactic Centre . There's something really weird in the centre of the Milky Way . The vicinity of a supermassive black hole is a pretty weird place to start with, but astronomers have found six objects orbiting Sagittarius A* that are unlike

Breaking News: Astronomers found a mysterious and strange object near the milky way black supermassive hole of the galactic core and they think it could be

But G1 and G2 weren't behaving like gas clouds.

"These objects look like gas but behave like stars," said physicist and astronomer Andrea Ghez of the University of California, Los Angeles.

Ghez and her colleagues have been studying the galactic centre for over 20 years. Now, based on that data, a team of astronomers led by UCLA astronomer Anna Ciurlo have identified four more of these objects: G3, G4, G5 and G6.

  Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way © Anna Ciurlo/Tuan Do/UCLA Galactic Center Group

And they're on wildly different orbits from G1 and G2 (pictured above); all together, the G objects have orbital periods that range from 170 years to 1,600 years.

It's unclear exactly what they are, but G2's intact emergence from periapsis in 2014 - that is, the closest point in its orbit to the black hole - was, Ghez believes, a big clue.

Interstellar Stardust Found Inside Australian Meteorite Is A Staggering 7 Billion Years Old

  Interstellar Stardust Found Inside Australian Meteorite Is A Staggering 7 Billion Years Old A meteorite that crashed into Australia back in 1969 contains stardust dating back some 7 billion years, predating the formation of Earth by 2.5 billion years. The remarkable discovery offers a snapshot of the conditions that existed long before our solar system came into existence. Ancient grains found inside the Murchison meteorite have been dated to between 5 billion and 7 billion years old, according to new research published in Proceedings of the National Academy of Sciences. The new paper was led by astronomer Philipp Heck from the University of Chicago.

Astronomers have found six strange objects orbiting the Sagittarius A* supermassive black hole at the center of the Milky Way , which are unlike However, as the astronomers observed them over time, they realised that G1 and G2 weren't behaving like gas clouds at all, but actually more like stars, with

The Milky Way is the galaxy that contains the Solar System, with the name describing the galaxy 's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be

"At the time of closest approach, G2 had a really strange signature," she said.

"We had seen it before, but it didn't look too peculiar until it got close to the black hole and became elongated, and much of its gas was torn apart. It went from being a pretty innocuous object when it was far from the black hole to one that was really stretched out and distorted at its closest approach and lost its outer shell, and now it's getting more compact again."

Previously, it had been thought that G2 was a cloud of hydrogen gas, which was going to get torn apart and slurped up by by Sgr A*, producing some supermassive black hole accretion fireworks. The fact that nothing happened was later referred to as a "cosmic fizzle".

The astronomers believe that the answer lies in massive binary stars. Most of the time, these twin stars, locked in a mutual orbit, hang out just doing their buddy star thing. But sometimes - just like colliding binary black holes - they can smoosh into each other, forming one big star.

Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way

  Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way There's something really weird in the centre of the Milky Way. The vicinity of a supermassive black hole is a pretty weird place to start with, but astronomers have found six objects orbiting Sagittarius A* that are unlike anything in the galaxy. They are so peculiar that they have been assigned a brand-new class - what astronomers are calling G objects. The original two objects - named G1 and G2 - first caught the eye of astronomers nearly two decades ago, with their orbits and odd natures gradually pieced together over subsequent years.

Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way . There's something really weird in the centre of the Milky Way . The vicinity of a supermassive black hole is a pretty weird place to start with

Strange Objects Found at The Galactic Centre Are Like Nothing Else in The Milky Way .

When this happens, they produce a vast cloud of dust and gas that surrounds the new star for about a million years after the collision.

"Something must have kept [G2] compact and enabled it to survive its encounter with the black hole," Ciurlo added. "This is evidence for a stellar object inside G2."

So what of the other five? Well, they could be binary star mergers too. Most of the stars in the galactic centre are very massive, and most of them are binaries. And the extreme gravitational forces at play around Sgr A* could be enough to destabilise their binary orbits with relative frequency.

"Mergers of stars may be happening in the Universe more often than we thought, and likely are quite common," Ghez said.

"Black holes may be driving binary stars to merge. It's possible that many of the stars we've been watching and not understanding may be the end product of mergers that are calm now. We are learning how galaxies and black holes evolve. The way binary stars interact with each other and with the black hole is very different from how single stars interact with other single stars and with the black hole."

It does seem like the G objects have a lot in common, whatever they are, and expanding the dataset can only provide more information to tease out the puzzle. There is, however, still a lot to figure out. Like some mysterious fireworks spotted flaring out of Sgr A* last year.

Was that a delayed reaction from G2's periapsis? Was the cosmic fizzle not so fizzly after all? We might just have to keep watching this weird little supermassive black hole corner of space to see what happens next...

The research has been published in Nature.

The Afterlife of Broken Spacecraft .
After spacecraft retire, they can still spend hundreds, even millions, of years trailing the Earth.The growing expanse, now hundreds of millions of miles wide, has made it trickier for engineers to operate Spitzer and point it at the right places—the sun, to charge itself; Earth, to transmit data; and the dusky universe beyond, to collect even more. So, they’ve decided to junk it.

—   Share news in the SOC. Networks

Topical videos:

usr: 1
This is interesting!