Key Takeaways
- Astronomers may have found a starless “primordial galaxy,” a vast cloud of hydrogen gas in today’s universe.
- The galaxy-sized mass, named J0613+52, spans around 270 million light-years from Earth.
- Discovered accidentally, this potential “dark galaxy” was first noticed through a mistyped coordinate error.
- Observations reveal no stars, suggesting the gas is spread too thinly for gravitational collapse.
- Follow-up studies aim to confirm this rare object by detecting its faint, possibly invisible light signature.
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Primordial galaxy J0613+52, about 270 million light-years away, lacks any star formation.
A Hidden Galaxy of Pure Gas Discovered
Astronomers believe they’ve found a galaxy frozen in time, revealing a rare glimpse into early galactic evolution. During a coordinated study involving the Green Bank Telescope (GBT) in West Virginia and the Nançay Radio Telescope in France, researchers noticed an unusual discrepancy between the two sets of data. GBT detected something that the Nançay Telescope could not observe, sparking curiosity and deeper investigation. As it turns out, an unnoticed error in the catalog coordinates led researchers to find J0613+52—a potentially dark, primordial galaxy existing as a massive cloud of cold hydrogen gas, free of stars.
Study leader Karen O’Neil, an astronomer from Green Bank Observatory, described this finding as a longstanding goal in galactic research. She and her team announced the discovery at the American Astronomical Society (AAS) winter meeting. Although further confirmation is needed, O’Neil and her team are excited about this potential look at the early universe, as primordial galaxies have long been theorized but are rarely observed in the modern universe. For the galaxy to be confirmed as primordial, it must show no signs of having initiated star formation, meaning its gas is not clumped enough for gravity to ignite any stars.
Detecting an Enormous Galaxy Without Stars
GBT’s radio signals showed a surprising feature: a galaxy-sized cloud of hydrogen with a mass comparable to billions of Suns, rotating at a speed similar to the Milky Way’s. But when researchers checked in visible light, the area seemed empty. J0613+52, located roughly 270 million light-years from Earth, appears to lack any gravitational disturbances from nearby galaxies, a factor that may contribute to its starless state. O’Neil explained that it’s likely a primordial galaxy, never forming stars due to its gas cloud’s isolation and undisturbed nature.
Confirming this rare discovery would provide insights into early galactic structure and star formation. Most galaxies form stars as gravity draws gas clouds together. However, this galaxy appears spread out, leaving it stable enough to avoid this process. Primordial galaxies were expected to be difficult to find in the nearby universe, as O’Neil noted, because previous hydrogen surveys, such as those conducted by the Arecibo Observatory in Puerto Rico, have found no such candidates until now. If confirmed, J0613+52 could change how scientists understand the timeline and triggers of star formation in galaxies.
Next Steps for Confirmation
The research team now hopes to secure time on a large optical telescope to make the final confirmation. Paradoxically, astronomers will be looking to see nothing in the visible spectrum—another sign that J0613+52 is made only of gas and is undetectable in optical light. Regardless of the results, finding no stars in such a massive galaxy would confirm this as a primordial galaxy and open a new avenue in galactic evolution research. If optical observations fail to reveal anything significant, it will provide further evidence for the object’s primordial nature, likely offering a unique window into what the earliest galaxies in the universe may have looked like.
Karen O’Neil expressed cautious optimism, acknowledging that decades of searching might have finally paid off. While the possibility of confirming a primordial galaxy is thrilling, she remains careful, saying, “Is this really it this time? Did we do it?” This possible discovery could provide astronomers with unprecedented insights into how galaxies began evolving billions of years ago and may be the first evidence of a starless galaxy in our universe.
You miss 100% of the shots you don’t take – Invisible Galaxy
So… not a galaxy, just a molecular cloud that may someday form a galaxy.
Interesting story, but hard to know precisely what is going on because I don’t think this result is published yet. From reading this over, it sounds like a result announced at the annual meeting of the American Astronomical Society back in January, and they’re still doing some follow-up to try and confirm the true nature of this object.
All stars are born in dusty clouds of hydrogen gas called nebulae, and studying the star formation rate of different galaxies in order to learn how they form is a very active area of astronomical research. For this to happen you need a few things, but one is the gas has to be dense enough to then collapse into stars. Hydrogen gas in itself doesn’t give off visible light if there’s no stars in it- instead, the best way to study the amount of hydrogen gas is in radio, specifically at the hydrogen line at 1.42 GHz (where neutral hydrogen emits).
Now, through pure chance this group stumbled upon a galaxy, named J0613+52, and about 270 million light years away, that appears to have a lot of hydrogen emission, indicating a lot of gas… but if you look with optical telescopes, there is no galaxy there! That’s very strange for sure! I suspect the results are still not in a journal because they said they’re now doing follow-up with more time on optical telescopes to do due diligence, but even if they find something it’s pretty clear this is a very low surface brightness galaxy. Most likely the density in this galaxy just isn’t high enough to host a lot of star formation- that is, just a blob of gas the size of a galaxy, hanging out since the dawn of the universe, because it’s unable to collapse into stars.
So that’s a cool find for sure! Don’t think I’ve ever stumbled upon anything interesting in my mistakes on coordinate input except for a fresh source of embarrassment. 🙂
I wonder if a hypothetical near-light-speed craft would be able to travel through this area of space, or if there would be too much friction from the diffuse gas. Just a silly thought since my near-light-speed craft still needs some work.
I love how much we don’t know about the universe. Don’t get me wrong, it’s fucking terrifying. But it’s amazing how much amazing stuff is just out there, undiscovered, waiting to be found.
Since 95% of the stars that will ever exist have already been born, doesn’t that mean we assume this “galaxy” will never birth any stars? Otherwise that implies there could be infinite empty galaxies out there waiting to birth stars and the 95% number would be meaningless and impossible to know.
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