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Mysterious ancient galaxy becomes most distant object ever seen

Mysterious ancient galaxy beco...
The newly discovered distant galaxy HD1 is highlighted in the zoomed in box
The newly discovered distant galaxy HD1 is highlighted in the zoomed in box
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The newly discovered distant galaxy HD1 is highlighted in the zoomed in box
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The newly discovered distant galaxy HD1 is highlighted in the zoomed in box
A timeline looking back from the present to HD1
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A timeline looking back from the present to HD1

Astronomers have discovered the most distant object ever seen – a strange galaxy some 13.5 billion light-years away. Known as HD1, the galaxy may house a never-before-seen population of stars, or a supermassive black hole mysteriously ahead of its time.

HD1 and a slightly closer galaxy called HD2 were discovered using the Spitzer, Subaru, VISTA and UK Infrared telescopes, before the incredible distance was confirmed using ALMA. At 13.5 billion light-years away, HD1 is not just the most distant galaxy detected, but the most distant object of any kind ever seen. It pips the previous record holder, a galaxy called GN-z11, by more than 100 million light-years. Recently, astronomers discovered the most distant individual star ever found – Earendel, which lies 12.9 billion light-years away.

To look deep into space is to look back in time, and so that means we’re seeing HD1 as it was 13.5 billion years ago, which was just 300 million years after the Big Bang. As such, the galaxy could provide astronomers with a fascinating new glimpse into the early history of the universe – and it’s already revealing some strange insights.

A timeline looking back from the present to HD1
A timeline looking back from the present to HD1

It turns out that HD1 is extremely bright in ultraviolet wavelengths, which would suggest that some very energetic processes are occurring in the galaxy. The astronomers have two leading hypotheses about what could be going on there.

The first is that HD1 is busily forming new stars. But to produce that much light, not only would the galaxy need to be birthing stars far more quickly than expected, but they would be of a hypothetical type known as Population III stars. If confirmed, this would be the first direct detection of these early stars.

"The very first population of stars that formed in the universe were more massive, more luminous and hotter than modern stars," said Fabio Pacucci, lead author of the study. "If we assume the stars produced in HD1 are these first, or Population III, stars, then its properties could be explained more easily. In fact, Population III stars are capable of producing more UV light than normal stars, which could clarify the extreme ultraviolet luminosity of HD1."

The second possibility is that a supermassive black hole with a mass about 100 million times that of the Sun, lurks at the heart of HD1, and the excess UV light is produced as it chows down on dust and gas. But that would make it the earliest known supermassive black hole by quite a margin, which would raise questions about how such a monster grew so big so quickly.

Whatever’s going on in HD1, the team plans to investigate using the recently launched James Webb Space Telescope. This infrared instrument is specifically designed to probe farther back in space and time than any telescope before it, and is perfectly suited to solving mysteries like this.

Two papers on the discovery have been accepted for publication, one in The Astrophysical Journal and another in the Monthly Notices of the Royal Astronomical Society Letters.

Source: Harvard & Smithsonian Center for Astrophysics

5 comments
5 comments
Expanded Viewpoint
All of this talk about a "Big bang" occurring, it has been going on for several decades now, and nobody yet can explain just where all of the matter and energy of the physical universe came from in the first place to have a big bang!! A fire cracker that goes "bang" when lit was made by someone, right?? So where did all of the stuff that makes up the physical universe come from? Who or what created it? Some say it all began as a "singularity", but where did it come from and how? I want to see some logic and facts to back up these totally fantastic claims being made!! Why did it start out as one big glob of something, and why did it suddenly get released? WHO LIT THAT FUSE?!?! The Big bang theory was totally obliterated in the early 1970s in Alvin Toffler's book Future Shock. If all of the stars came from a homogenous singularity exploding, then we should see many stars with the same spectrographic profile, but they are all as different as snowflakes!! A twenty year long study of stellar spectra, couldn't find a single match in many thousands of recordings!! Why is such a thoroughly discredited theory still getting any press coverage??
Username
It seems strange to refer to a galaxy as an object.
Nobody
Since all of the heavier elements supposedly were created and distributed by early supernovae, where are the Hubble photos of galaxies full of them billions of light years away and closer to the presumed time of the big bang? Supernovae should be popping all over in the early universe. The early universe should look like a fireworks show unless current theory is totally wrong which I think it is. I think the universe is much, much older than 13.7 billion years. 50 to 100 billion years would better explain expansion, multiple generations of stars, the mass distribution of heavier elements and the dark matter of generations of burnt out stars that were too small to go nova that are now cold and invisible cinders only detectable by the gravity they produce.
lon4
A distance from Earth of 13.5 billion lightyears. So, let's assume the universe expands away from a central point. We must then be looking past the center of the universe at these old stars and galaxies. If the universe is in fact close to 14 Billion yers old. But what if the shape of the first formation of matter was flat like a sheet, not a ball-like cluster?
christopher
@Expanded Viewpoint: What do you get when you add +1 with -1 ?
How is it so hard to comprehend the other direction? You can just as easily split "nothing" into a "something" and an "anti something".
If you want to understand science, you need to stop reading Tossers techno-phobic fiction, understand that a Man with no education is incapable of understanding modern reality, and concentrate on actual science, instead of nostalgic social mumbojumo. You know - LEARN science, instead of fighting it with other-peoples ignorance.