After more than a century of speculation, data seem to confirm that Betelgeuse (the brightest star in the Orion constellation, shown here) has a much smaller star as an orbital companion.
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Two independent studies found evidence of a star about the same mass as the sun, orbiting Betelgeuse about once every 2,100 days.
If dark matter is fully explained by such black holes, their most likely mass, according to some theories, would range from 10^17^ to 10^23^ grams—or about that of a large asteroid.
In case this doesn’t tell you a lot, 10^17^g is half the weight of Mount Everest, and 10^23^g is 4x the weight of the Antarctic ice shield.
The earth is estimated to “weigh” 13,170,000,000,000,000,000,000,000 pounds. (That is weird when you think about it. The weight of the earth being based on what something weighs on earth, I mean.)
Mt. Everest is only about 357,000,000,000,000 pounds and is just a tiny fraction of the mass of the earth.
So. My point is that we need a better way to portray scale of things in the universe. AUs work to a point but then we have to quickly move to parsecs. Parsecs quickly give way to light years. (Or vice-versa, depending on how you visualize things better.) Light years kinda work, but only for between 14-26 billion years. Even after all of that, I can hardly still fathom the size of Mt. Everest. (This was a rant, but not an angry rant.)
Weight in pounds isn’t the right unit here. Weight varies depending on the strength of the gravitational field you’re in, whereas mass does not. A kilogram here on earth weighs 2.2lbs but on the moon it only weighs 0.36lbs.
In the English Engineering System, the unit of mass is 1 pound mass (lbm), and is equivalent to the amount of matter that weighs 1lb at 1G. I won’t argue that EES is a good system, but it does at least have a kludged unit for mass. It has an equally kludged unit for force, too, called pounds force (lbf).
I cannot fathom the size of anything on an astronomical scale. I have seen the videos that zoom out and show Earth at scale with the Sun and then the Sun at scale with other stars. No matter how many times I view the facts it will be incomprehensibly large.
What if dark matter is some form of black hole or exotic ultra dense material made entirely out of the missing antimatter, which for whatever reason doesn’t otherwise interact with electromagnetism? 2 birds, 1 stone.
You don’t need the event horizon, you just need local gravity around 1G. For the masses described in the article, that radius is from hundreds of meters to 10s of kilometers.
Which still wouldn't do what you suggest. The mass is the same, so it has the same effect from a distance. Unless by "eat earth" you meant it would take in dirt until it suck to the core, still about the same mass.
Yes, it would just be surprising because, gravity should make them not be evenly distributed.
The whole thing with dark matter is that it’s this magic stuff that causes gravity but isn’t affected by it, which… is not how gravity normally works.
Though there is still room for it, we just need a better framework other than “I added 3 and 5 and got 12, so obviously I must mean to add 3 and 5 and 4 too”.
Then it should also coelescce, particularly since it doesn’t have the em force to keep it repelled, the universe should be dominated by massive dark matter black holes.
Yes, there’s math that explains part of the distribution, but also there is 0 force opposing any collapse we’d have a lot more neutron stars and other degenerate matter catalyzed by dark matter.
We have hypotheses like this when our observations don’t make sense and we need to explain them, it’s definitely a possibility but we still have room to understand the large scale physics at play.
You don’t need a force to prevent collapse if there’s no drag force to slow things down. It would actually be almost impossible for a cloud of dark matter to collapse since any individual particle has momentum and no way to slow down, so they’ll all be in some sort of mutual orbit
I’m guessing you’ve seen as many lorentz attractor simulations as I have, what always happens is something like tidal effects or angular momentum means 90% slow down while a few particles get shot out of hell at ludicrous speed.
The effect is similar to drag, and is basically how we get entropy even without em effects.
Would a regular asteroid be able to wobble the earth as described in this article? Or is it just black holes that should do so?
I seem to remember reading that primordial black holes weren’t yet a proven phenomenon and I have trouble imagining them myself. Wouldn’t they have hawking radiation too which we would be able to detect?
As someone that uses Starlink due to nothing else being in my area, I hate everything about this. Sure the convenience of having internet wherever I want is nice, but this still sucks. Especially since I’m a huge space nerd so this shit just hurts my soul.
My favorite part is that bout 5 miles down the highway they have fibre optic. They’ve been “installing” it for about 4 or 5 years now. They’ve had the spool just sitting outside for half that time.
But people are still shilling for starlink. I was always downvoted for mentioning the kessler syndrome or light pollution. All for progress, I guess we really need that fast internet in the middle of the atlantic.
People down voting you for bringing up Kessler syndrome were correct to do so. It’s a complete non-issue for starlink-sized objects at that altitude.
Light pollution is a more reasonable objection, and the effects on the upper atmosphere of all those satellites burning up would be as well, but not Kessler syndrome
It’s a complete non-issue for starlink-sized objects at that altitude.
Yeah. The mass and altitude are too low.
The thing with Kessler Syndrome is that collisions create debris, which cascades with more collisions, until there’s too much debris. But each collision actually results in the loss of kinetic energy or gravitational potential energy overall, so that the subsequent pieces are less energetic and/or less massive. Start with enough mass and enough altitude, and you’ve got a real problem where it can cascade many, many times. But with smaller objects at low altitude, and there’s just not enough energy to cause a runaway reaction.
Fellow dark sky supporter. Between all the led billboards, sprawl, and all the attempts at education failing… I doubt our children will have any view of the stars at all.
Unless there’s a hurricane that’s wipes out power… Stargazing was excellent for a few nights then.
If it can be infinitely dense inside a black hole, doesn’t that mean the scale doesn’t matter and that the ‘inside’ is pretty much it’s own whole universe with different physics rules?
Mathematically, it’s possible, but scientists are still skeptical about whether or not they are real. They’re called white holes and you can actually create a model of one in your kitchen sink. If you let the water just hit the bottom and spread out evenly in all directions, you can kind of visualize the way it’s supposed to work. Action Lab on YouTube actually has a pretty good video about it which I suggest watching if you’re interested. youtu.be/p3P4iKb24Ng?si=b3_RHuj0J3F_7DC1
Tangent, but you don’t need to include the question mark or anything after in most urls. Definitely not YouTube links. It’s just YouTube telling itself who shared the info (you) and they use that to track shit. But the link works just as well without it, and you’re not voluntary spying on yourself.
It’s not the only problem with them, and potentially not the biggest either - there is no plan to remove or maintain them when they die other than de-orbiting them into the upper atmosphere. A recent study suggests that this will critically harm the ozone layer, and that adding metallic particles in the quantities implied by the number of starlink satellites that Elmo plans to launch could do far more damage to the ozone layer than our previous attempts to screw it up!
Any chance the Starlink satellites could be built to double as a sort of large-array telescope themselves, to compensate for the ground-based interference?
What’s more likely to happen is Starship’s will be launched where the entire ship becomes the telescope, and then we’ll have arrays of these much further away.
Not sure if it’s the same for radio, but for optical that means we can get a 9 meter mirror up there without any expensive folding mechanism, and who knows how big if we fold them as the fairing is not only wider but also longer.
Cost would go from billions to hundreds of millions or less. James Webb cost 10b.
The James Webb folding mirror is 6.5m and was folded into a 4.5m fairing…
From my brief look into the topic, interferometry tech is not quite there yet, but might be in the next few decades. Interferometry is more difficult with shorter wavelengths.
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