#early galaxies

[zespaceblog]

The First Galaxies

JWST has already been tearing through the old assumptions about early galaxies, finding Milky Way sized galaxies literally a few 100 million years into the Universe has been one of the major findings of JWST data so far, but a team of Astronomers from the Cosmic Dawn Center based in Denmark suspect, these galaxies may even be larger than we expect, in some cases MUCH larger.

The SMC (sometimes referred to as ΛCDM Model) expected stars and galaxies to start forming around the 400 million years after the Big Bang, with small galaxies appearing after this, and much larger complex galaxies like our Milky Way further along.

JWST has challenged this, showing galaxies a few hundred million later already being as large as the Milky Way, but assessing the mass of a galaxy that's a red shifted smudge in the background of an image has it's challenges too.

Previous attempts would take the light output from the entire galactic blob, and infer a mass size from this, however the team believe a better and more accurate approach would be to take the image and assess the mass pixel by pixel, and when they did so, they found the galaxies were considerably larger than had previously been expected.

The reason for this is evident above in the image of NGC 1376, when you view a galaxy, the largest and often new born blue stars stand out far more than the smaller but way more numerous stars. It's easy to assume that the galaxy above has only blue giants in the arms, and the more yellow colour towards the centre represents more mix, but the simple reason for this is, the blue stars die long before they make it to the centre, leaving the longer lived stars to be significantly more prominent, they are just as abundant elsewhere, but drowned out in the diamond like clusters of new stars.

This of course is a rough estimate, and far more evidence is needed to be sure that what is being assumed to be seen, is really what is there, and techniques like this may also turn out to have their very own errors and over estimations.

It was maybe comfortable to have a neat little theory of the SMC, with little or no data to challenge it, now comes the evidence by which theories adapt. It's an exciting time thanks to JWST.

[zespaceblog]

12 Billion Year Old Einstein Ring

JWST has been busy scanning the Universe around us, in this image said to have been taken from data captured earlier and recently processed, the galaxy SPT-S J041839-4751.8 can be seen as a blue object with a yellow ring around it.

The blue object is a very heavy mass object in front of a galaxy whose light is then lensed around it, making the Einstein ring. Not only does the light bend, it can act like a magnifying glass, making details of the galaxy visible that would otherwise not be.

The object is thought to have spent the last 12 billion years travelling towards us, making it within the first 1 billion years of the Universe. Due to the expansion of the universe, it will be MUCH further away now, but what we are seeing here is a snapshot of it's earlier self.

The light around the object is twisted and repeats itself, making it hard to discern what it may look like, but scientists have been able to untangle these rings before.

Earlier readings of this galaxy from ALMA had been used to remove the central galaxy, leaving only the ring, then to unwrap it to find out what the galaxy behind looked like.

To their surprise, what they found was a galaxy not too unlike our own Milky Way, meaning that galaxies back at the start of the universe, were quickly assembled and looked not too dissimilar to the ones we see around us today. JWST has certainly brought that fact to the fore, with galaxies now being spotted right back to 150 million years after the big bang, albeit smaller and more globular in shape (so far).

Caution should always be taken with using this kind of data to prove or disprove theories, often we see only what the tools we have can show us, and it's part of a picture from a very specific view. I'm also always rather cautious of "some guy on Reddit says" ... Like our recent Sausage image of Proxima Centauri as a perfect example. So here's the sources for all interested to make your own mind up.

Source :

Webb Has Snapped an Almost Perfect Einstein Ring In Distant Space

Since the first James Webb Space Telescope images were released in July, our feeds have been flooded with mind-bogglingly gorgeous photos of

Spaceguy44 (u/Spaceguy44) - Reddit

u/Spaceguy44: Astronomy grad student who also really likes classical music and music composition

ALMA Finds Young Milky Way-Like Galaxy in Early Universe | Astronomy | Sci-News.com

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered an extremely distant galaxy that looks surprisingl

[trwtitles]

JWST Confirms the Oldest Galaxy Ever Observed—JADES-GS-z13-0

JWST Confirms Oldest Galaxy Yet—JADES-GS-z13-0 Reshapes Early Universe Models The James Webb Space Telescope has once again redefined the edge of the observable universe. In a historic breakthrough, scientists working with the JWST Advanced Deep Extragalactic Survey (JADES) have confirmed the oldest galaxy ever observed—JADES-GS-z13-0—clocking in at a redshift of z ≈ 13.2. That puts this galaxy…

JWST Confirms the Oldest Galaxy Ever Observed—JADES-GS-z13-0

[naonicblog2]

Webb might have found something the universe no longer makes — Mashable

Astronomers are baffled.

[tncwrapup]

Mysterious Dark Matter Is Missing In Ancient Galaxies

Mysterious Dark Matter Is Missing In Ancient Galaxies

Mysterious Dark Matter Is Missing In Ancient Galaxies By Judith E Braffman-Miller The Universe keeps its secrets well. Long before there was anything around with eyes to see, the galaxies formed, and the myriad of sparkling, brilliant stars were born–lighting up what had previously been a barren swath of featureless darkness. The most widely accepted theory of how the galaxies were born proposes…

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[astro-grafica]

Milky Way-like galaxies may have existed in the early universe

Carnegie Mellon University’s current simulation, called BlueTides, is 100 times larger than previous simulations.

A new, large-scale computer simulation has shown for the first time that large disk galaxies, much like our own Milky Way, may have existed in the early days of the universe.

The simulation, created by physicists at Carnegie Mellon University’s McWilliams Center for Cosmology and the University of California Berkeley, shows that the early universe — 500 million years after the Big Bang — might have had more order and structure than previously thought.

Their findings will help researchers using next-generation telescopes like the Wide Field Infrared Survey Telescope (WFIRST) and the James Webb Space Telescope (JWST) as they search the sky for evidence of the first galaxies.

“It’s awe inspiring to think that galaxies much like our own existed when the universe was so young,” said Tiziana Di Matteo, professor of physics at Carnegie Mellon. “The deepest Hubble Space Telescope observations have thus only covered small volumes of space and have found very irregular, clumpy galaxies at these early epochs. It is not surprising that in these small volumes some of the small galaxies do not have regular morphologies like large disk galaxies. Similarly, numerical simulations have been limited in size so they have only made predictions for the smaller, clumpier galaxies at these early times.” Di Matteo and fellow CMU Physics Professor Rupert Croft have long been at the forefront of simulation cosmology, completing some of the largest simulations ever created. Their current simulation, called BlueTides, is 100 times larger than previous simulations. It was so large that it monopolized all of the National Science Foundation (NSF) supercomputer BlueWater’s memory and almost 1 million CPUs in order to complete the simulation.

Di Matteo, Croft and their former graduate student Yu Feng, now a post-doctoral researcher at UC Berkeley, began by seeding their simulation with constraints provided by the cold dark matter theory, the prevailing theory that explains what may have happened in the universe after the Big Bang.

After the simulation was completed, the researchers looked at their data to see what they could find, much like observational cosmologists would do with data gathered using a telescope. They were surprised to find a number of disk galaxies in the universe at 500 million years post-Big Bang. Since disk galaxies are so large and complex, most researchers assumed that they would take a very long time to form and would be rare, if they existed at all, in the early universe.

“Theoretically we thought that when the universe was only 5 percent of its present age, it would be a place full of chaos and disorder,” Croft said. “Our simulation showed that the early universe might be far from being just this. It might contain beautiful symmetrical galaxies, like the Milky Way.”

From their simulation, the researchers were able to make predictions about the galaxies’ luminosities, angular sizes, morphologies, colors and expected number. When telescopes like WFIRST and JWST come online, they will be able to search for galaxies that fit the descriptions developed by the BlueTides simulation. If simulation and observational results match, it could be a strong proof of the cold dark matter theory.

“Right now, we’re converging on an exciting time in cosmology. Previously, we couldn’t study disk galaxies in the early universe using telescopes because the galaxies were so faint and rare. We couldn’t study them in a computer because no computers were large enough to cope,” Di Matteo said. “The technology has caught up, and we can complete the simulations using today’s large supercomputers, and we will be able to use telescopes like WFIRST to make the observations.”

[customstoday]

Supernovas creates dust in early universe

Supernovas creates dust in early universe

HONG KONG: Cosmic dust consisting of iron, carbon, and oxygen are an important part of solar system formation. Early galaxies consisted only of gas, and scientists have been trying to figure out where the dust came from for a long time. Now, astronomers have published a paper in Science, showing that they have identified cosmic dust that appears to have survived the massive explosion of a…

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