Discovered: Fast-growing galaxies from early universe

Discovered: Fast-growing galaxies from early universe
Artist's impression of a quasar and neighboring merging galaxy. The galaxies observed by the team are so distant that no detailed images are possible at present. This combination of images of nearby counterparts gives an impression of how they might look in more detail. Credit: The image was created by the Max Planck Institute for Astronomy using material from the NASA/ESA Hubble Space Telescope.

A team of astronomers including Carnegie's Eduardo Bañados and led by Roberto Decarli of the Max Planck Institute for Astronomy has discovered a new kind of galaxy which, although extremely old—formed less than a billion years after the Big Bang—creates stars more than a hundred times faster than our own Milky Way.

Their findings are published by Nature.

The team's discovery could help solve a cosmic puzzle—a mysterious population of surprisingly massive from when the universe was only about 10 percent of its current age.

After first observing these galaxies a few years ago, astronomers proposed that they must have been created from hyper-productive precursor galaxies, which is the only way so many could have formed so quickly. But astronomers had never seen anything that fit the bill for these precursors until now.

This newly discovered population could solve the mystery of how these extremely large galaxies came to have hundreds of billions of stars in them when they formed only 1.5 billion years after the Big Bang, requiring very rapid .

The team made this discovery by accident when investigating quasars, which are that sit at the center of enormous galaxies, accreting matter. They were trying to study star formation in the galaxies that host these quasars.

"But what we found, in four separate cases, were neighboring galaxies that were forming stars at a furious pace, producing a hundred solar masses' worth of new stars per year," Decarli explained.

"Very likely it is not a coincidence to find these productive galaxies close to bright quasars. Quasars are thought to form in regions of the universe where the large-scale density of matter is much higher than average. Those same conditions should also be conducive to galaxies forming new stars at a greatly increased rate," added Fabian Walter, also of Max Planck.

"Whether or not the fast-growing galaxies we discovered are indeed precursors of the massive galaxies first seen a few years back will require more work to see how common they actually are," Bañados explained.

Decarli's team already has follow-up investigations planned to explore this question.

The team also found what appears to be the earliest known example of two galaxies undergoing a merger, which is another major mechanism of galaxy growth. The new observations provide the first direct evidence that such mergers have been taking place even at the earliest stages of galaxy evolution, less than a billion years after the Big Bang.


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More information: Rapidly star-forming galaxies adjacent to quasars at redshifts exceeding 6, Nature (2017). nature.com/articles/doi:10.1038/nature22358
Journal information: Nature

Citation: Discovered: Fast-growing galaxies from early universe (2017, May 24) retrieved 19 October 2019 from https://phys.org/news/2017-05-fast-growing-galaxies-early-universe.html
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May 24, 2017
LOL. Merger maniacs desperate to hold fast to their Huge Bang Fantasy.

"Very likely it is not a coincidence to find these productive galaxies close to bright quasars.

Indeed, since super-duper massive quasars make the galaxy appear extremely distant due to tired light climbing out of a deep gravity well. Very likely, some of these galaxies are instead not so distant as assumed.

The team also found what appears to be the earliest known example of two galaxies undergoing a merger, which is another major mechanism of galaxy growth.

Again, a merger maniac assumption. More likely they are diverging, rather than merging. Bright very active cores in observable galaxies at that distance are much more likely to spawn daughter galaxies diverging therefrom. Perhaps the authors should have reviewed my comments in this story for an explanation.

https://phys.org/...ole.html

May 24, 2017
What a mess they find themselves in. And yet, they keep pushing forward.

It really does seem that we've set up a system with the graduate programs which absolutely precludes the sort of courageous response required to extricate the domain from this quagmire.

May 25, 2017
@Tuxford
This is not a criticism, just a genuine question. (I'm aware of the often heated flaming in these fora on this and other topics so wanted to preface with that note.)

I assume (but correct me if I'm wrong) that by "tired light" you mean redshifted by the putative gravity gradient you speak of?
Very likely, some of these galaxies are instead not so distant as assumed.

I'm curious to know, how would you go about proving that this (your quote above) is the case, versus the overt reasoning in this article (i.e. that it is a factor of distance and intervening matter)? This seems, on the face of it anyway, a difficult problem to resolve?

May 25, 2017
I'm curious to know, how would you go about proving that this?

You guys don't trust your intellectual insight? So you always need proof. I prefer to follow the preponderance of evidence, which seems to point to 'tired light' and LaViolette's Continuous Creation model.

http://starburstf...smology/

For more than five years now, I have yet to find an observation that cannot be easily fit within his SQK model of physics and cosmology. No doubt some of his work is wrong, as it is still incomplete. But this is a complicated subject! Help is needed, instead of constant derision. But the community is committed now to Fantasy. So help will not soon come.

Anyway, you follow my comments regarding the Pioneer Anomaly (to follow), which I found as compelling evidence to consider. Finally, as an old servo engineer, I understand reactive systems a bit more than your average simple-minded cosmologist, who I know can never quite grasp the fundamentals of SQK.


May 27, 2017
I think you scared @malapropism off, @Tuxford, but not by being right, but by being a nutjob.

Yay! <- sarcasm, idiot

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