These are the massive black holes that lurk at the core of most galaxies. Like the one at the center of our own milkyway galaxy. The question remains do they form at the center of baby galaxies or are they the seed which triggers a galaxy to develop and they just grow even larger over time. If early galaxies had massive black holes for their galaxy size, that suggests the last option. Primordial black holes that is ones that were formed in the big bang have been a possibility for a long time. They have been talked about by astronomers since the 1970s. It great that so much is being discovered now. Lots of surprises still coming I suspect. More info on primeval black holes here. https://physicsworld.com/a/concerning-primordial-black-holes/
“Ok boys, we need ideas. We’re fucking the planet up irreparably in a way that will cost many, many millions of lives… but I feel like we could be doing it a lot faster. Get off your ass and invent a way for rich assholes to screw us even more than they already are”
given the age of the Universe and the relatively short time it would take for an advanced civilization to spread across the Milky Way Galaxy (650,000 years, by Hart’s estimate), Earth should have been visited by an extraterrestrial civilization (ETC) by now.
It took humans 30,000 years to cross the Atlantic. Using modem propolsion systems, it takes us two years to get to Mars and 40 to reach the edge of the solar system. This seems like an extremely generous estimate considering the Milky Way has a 50,000 light year radius.
I’m as bullish about extraterrestrial life as anyone, and I think a fuller survey of even just the current Solar System has potential. But I have no idea how you get a full galactic survey in so short a time, given what we know about the soft limits on speed of travel and communication.
By Tipler’s refined estimate, an ETC would be able to explore the entire galaxy in “less than 300 million years.”
That definitely feels like it’s more in the ballpark. But, again, it presumes a certain amount of steady cartography by the hypothetical fleet of Von Neuman probes.
There’s a Sci-fi series called The Bobverse that explores the idea of a sentiment fleet of Von Neumans exploring the galaxy, and the various trial and tribulations involved. One point it discusses is that even with a saturation of probes, you don’t get real time communication. So even in a hypothetical universe where alien life did exist and survey earth, what are they odds they’d be watching us at the moment of our development. What would an alien AI be looking for and what would it do when it was discovered?
We could still be too primitive to bare noticing. Or we could be living in between blinks of an alien camera that only reports back every 1000 years.
As we look out at the cosmos, we could be looking at things we don’t understand. After all, what does a star surrounded by a Dyson Sphere look like to a telescope that is searching for glimmers of light, heat, and gravity? SETI is operating purely on conjecture. That’s assuming alien civilizations are even capable of creating these hypothetical superstructures. Or that the structures would function as we intuit.
At some level, I have to question if we know what we’re looking for. Because so much of this feels like we’re searching for humans deep in space. Perhaps the reason we can’t find aliens is that they are simply… too alien.
In case anyone wasn't aware, nearly all space photos that you've ever seen have had their colours tweaked. It's standard practice in space photography. Nebulae and galaxies and planets aren't as colourful as they appear in photos. They do it either to make the features more obvious for study, or just to make them pop more to drum up interest in space exploration. Nothing wrong with it, just be aware that what you see isn't reality but an interpretation.
Super cool photo, but does this technically count as astronomy? Isn’t astronomy “a camera on (usually) on earth, pointed up into space”, not the other way around?
The science which treats of the celestial bodies, of their magnitudes, motions, distances, periods of revolution, eclipses, constitution, physical condition, and of the causes of their various phenomena.
A treatise on, or text-book of, the science.
From the GNU version of the Collaborative International Dictionary of English.
astronomy
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