As Universe Today explored in a previous post, it would take between 19,000 and 81,000 years for a spacecraft to reach Proxima Centauri using conventional propulsion (or those that are feasible using current technology)
Acceleration is a bitch. A manned flight would take longer as it would have to cap it’s thrust to 1-1.5G or risk long term effects. Not to mention having to cancel ALLL of that thrust starting at the halfway point.
Biology is frustrating. We’re built for everything except leaving the immediate area around the sea we crawled out of. Anything beyond that and our bones melt into cancer.
The leading hypothesis is that the moon was formed when a massive asteroid smashed into the earth and blasted a huge chunk of the earth into space, and that became the moon. If true then the moon's birth and younger existence was wildly cataclysmic
They mention this in the article, but the physiology would suggest this is related to CSF/blood pooling in low G.
Taking it a step further, I bet this has a similar mechanism to IIH or the high pressure headaches you get with obstructive hydrocephalus. CSF is supposed to drain down via a relatively passive system. Without G to regulate this I can envision that you’d essentially develop the same physiology as someone with IIH (too much CSF).
Really interesting. A good example of how we have no idea what insane health things we are going to experience with space travel, but also how space travel may shed insight on treatments for other conditions with similar mechanisms we experience in a gravity well.
Haven’t this is interesting because I’ve always wondered how evolution would happen when we finally colonize in low g environs. Maybe char was on to something when he said our souls are weighed down by gravity.
How long until the young earth dipshits jump on this as “evidence” to claim that if there’s room to question whether the universe is 13.8 billion or 26.7 billion years old, that means it must actually be 6000?
The whole “dark matter” thing has never sat right with me. It always seemed like a desperate attempt to explain what we see. I’m not saying I know enough to have an informed opinion, but it has always seemed wrong. It is matter we can’t detect in any way except for gravity? Nah. The forces of nature changing due to expansion? Fits better somehow. Anyway, what do I know? I entertained the idea that it was time that was changing due to the expansion, but I couldn’t get it to fit. This seems more plausible.
I too don’t really know enough to have an informed opinion, but I don’t think “plausible” has much meaning in physics. It’s more a question of whether the mathematics supports the theory and/or if it can be proved somehow.
There are plenty of things that the mathematics predicted that seemed completely implausible, but were later verified to be true. “Quantum Entanglement” jumps to mind as something Einstein dismissed as “spooky action at a distance”, but it has since been confirmed.
I think you could consider all of physics or even all of science to be made up of placeholders meant to keep things moving until a better explanation comes along.
I think you could consider all of physics or even all of science to be made up of placeholders meant to keep things moving until a better explanation comes along.
I agree. I would add that intuition, common sense, and ideologies are also just placeholders in our journey to a better world.
When we discover someone we don’t understand we often make a simplistic metaphor to fit the data until we have better understanding. Like the Bohr model of the atom, or Newton’s theory of gravity. Dark matter plugs the hole right now and does it with a minimum of contrivance (Occam and whatnot)
Or the aether or the flat earth model. I know all this, but I still believe it is a bad and lazy model that stopped a lot of people from trying to find something else that could explain what we’re seeing, or not seeing actually. There is too much gravity, yes. What could produce that effect? Shit we aren’t seeing, dark matter, sure. But what if there’s no ‘extra’ matter? What other thing could produce the appearance of too much matter? Is time changing in some way we don’t know? Is light slowing down/going faster due to the expansion? Is there something else that we thinks is constant that is actually changing over time? Should I really smoke this much? I don’t know any of this obviously but I have a distinct feeling we are missing something with ‘dark matter’ as a model. I get why we use it, but I don’t like it. When we create a model, we fix it in our minds and it is very hard to break free from that mindset. Look what it took before we accepted that time is relative. What else is relative? What, besides mass, aren’t we seeing?
Of course I’m not the first to think about it and of course I’m not as smart as many, or most of those guys. But if you put up a grand model that’s largely unsubstantiated too early and everyone and their dog runs with it, you create a bias to try and prove it and more resources will be added to that than to find alternative explanations that night also fit the data. That is basically my gripe with dark matter as a name for the discrepancy between observable matter and “invisible” matter. It is too ad hoc, mostly added to try and save as much as possible of present understanding of how shit works. Must’ve stepped on a toe there, chief.
I really shouldn’t feed the trolls, but I have to ask - is she hot or is she a used up tramp like your mum?
That’s exactly what Dark Matter is. Scientists saw that galaxies were spinning faster than expected, did some math, and figured out that based on current, known physics, they wouldn’t be able to stay together.
So they said “huh, must be additional matter that we can’t account for, let’s call it Dark Matter for the time being, cause we can’t see it.” It might be one big type of thing, it might be a thousand smaller types of things that all add up to this collective Dark Matter, but whatever it is, it doesn’t behave the same way we expect normal, everyday matter behaves.
Other scientists said that we must not understand something about physics and gravity at larger scales.
Other scientists said that light must not act the way we expect, and it’s throwing off our measurements.
Based on follow up research, there is more evidence for unaccounted for matter, than the other options.
It’s entirely possible that none of those options are correct, but most of the data we have right now points to Dark Matter is the best fit for the evidence we have.
I’m aware we’ll never find the bottom truth, whatever that may be, it’s only better and better models. Sometimes though, the model chosen by the scientific community isn’t really a good one, despite fitting most of the data. I think dark matter, like the aether(spelling?), is one of those models. Again, I base this solely on the clunky, ad hoc feeling of the dark matter model and not of anything more substantial than that. If I’m wrong and they manage to find a chunk of dark matter I’m fine with that. The chunk part was a joke, btw, I’ll settle for detection or proof of existence.
The way I see it, Dark Matter is just a psuedonym for “Whatever is causing gravity to work differently at a galaxy scale than at a solar system scale”. And further, Dark Energy is just a term for “Whatever is causing gravity to work differently at an inter-galactic scale than at a intra-galactic scale or solar system scale”.
But, if we want to entertain the technical aspects of the thought, there’s nothing in the definition of Matter that says it interacts with anything besides gravity (light, magnetism, etc) on its own. Just that it has mass (ie generates gravity) and cant occupy the same space as other mass. We already know via colliders that the higs bosson is the sub-particle solely responsible for Mass, way smaller than the scale of an atom. And we also know that magnetism, electric charge, and by extension light rely on electrons, which exist only at the atomic scale. So its not implausible to think that mass can exist separate from any of the things that we can detect with our other favorite methods (pretty much just different wavelengths of light) besides just the gravity they generate. In this case, gravity IS the thing we’re using to detect it.
A few things not quite right here. Particles are given mass through interacting directly with the Higgs field itself. They don’t need the boson to be involved. Due to the way the math works out, the Higgs field has a non-zero value everywhere, so everything that interacts with that field is given mass by that.
Also, we know of weakly interacting matter such as neutrinos that can pass directly through other matter most of the time already. Things can be in the same place as long as the fields they’re part of don’t interact in a way that stops it.
Magnetism, electric charge, and light rely on photons, not electrons. Photons are the bosons of the electromagnetic field. Bosons are called force carriers. They get exchanged any time an electromagnetic force acts on anything. Electrons are a particle and made from the electron field. They are involved in a lot of electromagnetic interactions via photons, but not all of them.
“Whatever is causing gravity to work differently at a galaxy scale than at a solar system scale”.
Nothing is. Gravity works the same. We don’t just infer dark matter from gravity fields. We can detect and map the exact locations of dark matter thru gravitational lensing.
Cue the flat-earthers who are going to jump on this while completely ignoring all other aspects including the gravity required to make this happen, and somehow claim this is scientific proof that they were right.
Intriguingly, the two structures are at the same distance from Earth, near the constellations of Boötes the Herdsman, raising the possibility that they are part of a connected cosmological system.
Not only that, but they look suspiciously concentric when plotted out on the sky. I know that's jumping pretty far out there into speculation land, but it'd really blow our theories a new one if there are patterns in the cosmos this large. Neat stuff.
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