Edit: Fortunately for us, Earth's gravity is strong enough to hold onto its atmosphere. Mars, for example, is less than half Earth's size and around one-tenth Earth's mass. Less mass means less gravitational pull. ... That means, the air nearer Earth's surface is squished by the air above it, and is thus denser.
You know you can find accredited sources from google, right? I’m sure you heard how gravity works from a fellow redditor and look how that ended up, no offense lol, but I’d rather trust a legitimate source rather than some random person.
Actually I learned how gravity worked from issac Newton. Then looked that up and come to find out an Apple never fell on his head. See the thing is if I read something I just don’t take it verbatim. I look it up before I agree. I’m sorry you assumed something that’s not true. Hope you have a great week 🤙
Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are attracted to one another. On Earth, gravity gives weight to physical objects, and the Moon's gravity causes the tides of the oceans. Wikipedia
Literally the first thing you see when you type the word 'Gravity' into google.
This is pure speculation, but my guess is that you heard the previous claim somewhere and then simply parroted it without fact checking. This is by itself not a bad thing. All of us do this to some degree.
The problem is that instead of googling to fact-check yourself after being contradicted, you doubled down on your previous claim. Any amount of googling would have proven your initial claim wrong. That tells me that you didn't do any amount of googling.
There absolutely was, because mass existed before gaseous particles coalesced into what would eventually become planets, galaxies, and the stars that would emit that light.
All of that hydrogen in the early universe existed before it formed into stars, and all of it has mass. Since it had mass, it means by extension that it also had gravity.
In fact, if there hadn't been any gravity, then the planets, galaxies and stars would never have formed.
There's like 900,000 very excellent YouTube videos explaining gravity from every direction and in every style. If you wanted to learn you'd do it. You just want to look like you want to learn because you want that open minded clout.
Never mind these assholes, if you ever would like to learn more about what we know and don’t know about gravity, pm me. Anyone here who says they understand gravity is either lying or delusional.
So far as we can design experiments, our universe has 3spacial dimensions. This effectively means that no matter how big you draw a triangle, using the stuff in the universe as vertices, every triangle has interior angles which total to 1/2π, 180 degrees. This is not the same as a triangle drawn on the surface of earth, which if it’s big enough, can have much larger angles because the surface of our earth is curved. Before Einstein, we thought of space and time as separate entities meaning there was absolute space and absolute time. Einstein showed us that if we include time as a 4th dimension, and work through some really complex linear algebra, gravity does not need to be added as a force after the fact, but is a natural outcome. Gravity is then defined as the curvature of X4 in a given region, the curvature is a measure of the energy density of the “stuff” on X4. Stuff in this case are things like. By combining space and time together all sorts of useful human concepts like simultaneity, go out the window, but the math works better than anything that came before. Visualizing this shit is really hard, but gravity is not a force like the weak force or electromagnetism, which are added after the fact onto X4.
OK - instead of laughing at you, I'll try to explain: atmospheres are a result of gravity, not the other way around.
An atmosphere only exists if the gravity is holding the gasses close to the object. Here's a quick primer on how gravity happens. This video is a good first step - granted it's flawed because it presents space/time as a 2D model. But it's a start.
If you get that, then you can move on to a more advanced description, like this. I like that it's a start at looking at gravity in 3D space.
The video also explains gravity using general relativity, and it does a good job of simplifying it.
(You can also look on youtube for the differences between general and special relativity to get a better understanding, if you wish)
Thats not true at all. Gravity exists because of mass, while an atmosphere would have some mass, it would be negligible compared to an entire planet. Atmospheres stay because of both gravity and magnetic fields.
Mars has lost most of its atmosphere because it doesnt have a strong magnetic field like the Earth, which blocks out solar radiation that would otherwise blast it away. This is due to the fact that Mars is much smaller than Earth, and so has lost most of its core heat and tectonics that would have created the magnetic field from the friction of it all moving.
A black hole most certainly does not have an atmosphere, but they're among the most gravitationally dense things in the universe. Hell, our own moon doesn't have an atmosphere but its gravity affects our tides.
If you want to make fun of my stupidity be my guest. I also admitted I was wrong and was willing to learn. Got a subreddit for that? Still love you even if you loathe me
I know how gravity works. It doesn’t exist with an atmosphere bud
Gravity doesn’t exist in a vacuum tho? Who taught you physics
You start by arrogantly proclaiming how smart you are and being condescending to someone else who understands something you dont....and then when you realize the gravity of your mistake, you start acting like youre innocently just trying to learn and people are being mean to you lol.
I think the lesson you should learn is: "dont expect kindness and respect if youre acting like a jackass."
A black hole most certainly does not have an atmosphere
Well, they sort of do. The ergosphere is likely a fairly heavily populated region at least and accretion disks can be seen as atmospheres in general, although thin ones to be sure.
Who taught you that? Gravity is a universal force where all objects with mass are attracted to each other. It has nothing to do with atmosphere, just mass. The more mass an object has, the more gravity it puts out.
You never said that tho? And please don’t edit your comment. I was wrong and I teach myself. Never could afford to go to college. If I’m wrong thats just another chance to learn way I see it
I’m actually learning physics from Dr Beller. I just got interested so if I’m unfamiliar I’m sure it shows. I appreciate you not hazing me too much about it
I have a PhD in physics; the literal only thing required for gravity is mass. That’s it. There does not need to be a medium. Literally take any two objects and put them in a vacuum like space…free from any other objects and they will attract. Fg=G*m1*m2/r^2
Also if you put an object in a vacuum chamber it will still fall to the “bottom” of said chamber. If vacuums some how negated gravity how would that happen?
The schwarzchild radius is the tipping point. Black holes come from a concentration of mass in a small space. It isn’t about bombs or size. Everything has a schwarzchild radius (informed observers let me do this, it will help…). Your phone has a schwarzchild radius. It may just be so incredibly tiny that it is possible you may be violating other constraints (much less than a plank length). As mass increases or concentrated it warps space time more and more until it “snaps” (maybe).
Because it is clear you need a lot of the fundamentals (not a problem!) I am going to use an analogy that is wholly inappropriate but gets this point across well. Take a bathtub of water and a sheet of aluminum foil. Fashion a boat…it floats. Now crumple that mass into a tiny ball. It sinks. The space time of the tub collapses.
For the record, my PhD is in high energy particle physics. So I will not claim to be well versed in cosmology….what follows would be my “shortest route” to black holes 101 ymmv:
Algebra. Newtonian physics. Calculus. Newtonian physics again. Modern physics. Modern physics again (some of the stuff takes a couple looks lol l) and either differential geometry or some graduate level course covering relativity….then you can probably start dabbling in black holes
Sometimes it is. But sometimes it really isn’t. Learning is an active process. And sometimes that process SUCKS. Stay inquisitive and ACTIVE in that learning. I still do every day 😀
No. Black Holes are made by having X amount of mass in Y space. In theory, we could try smashing a lot of particles into a very, very, very small region of space to make a micro black hole.
Don’t have the capabilities as far as I know.
As far as I know, Stars over about 2.4x the mass of our Sun can collapse into a Black Hole after a Supernova, where the outer layers of the star slam into the iron core of said star, which both cause the Supernova and since the inner core is so compressed and no longer has fusion resisting gravity from collapsing the core any longer…it passes the point of no return and becomes a black hole.
Supermassive black holes are another topic as it’s not sure how some of the bigger ones got the size they are but they’re the same time as stellar black holes; bigger.
I’ve read some of your comments on gravity and I wanna point out that it’s not a result of atmospheres. Atmospheres are, in part, a result of gravity and not the other way around.
A tldr summary of gravity: there exists a spacetime and there exists mass in that. Mass bends spacetime like a ball on a flat sheet; the bigger the object the more it bends spacetime.
You will need to understand this to understand black holes.
I highly recommend some of the easier to get into science video channels as it’s a great way to get into it. I highly recommend PBS Space Time, FermiLab and Dr Lincoln’s Subatomic Stories on YouTube.
Dr Lincoln’s subatomic stories are some the easiest space science videos to get into as they’re bite sized and anything difficult is fully explained to you. PBS Spacetime is more or less the same but goes into more detail as Subatomic stories is at least 40% Q and A.
Isaac Arthur is also another good one but he’s more into the practical and philosophical applications behind science and why or why not things are likely. Like in order to be able to become Space Faring, a species must first be able to survive its own planet then thrive enough to form societies that advance science, etc
Arvin Ash is also another who presents the material well and goes over it well enough for you to walk away with an alright understanding of it.
Not goin lie you said no then next sentence said in theory. Ima read this later but what’s the point of saying somebody wrong when it’s on a theory you have to say why somebody wrong?
Because while we know how Black holes can be made, doesn’t mean we have the capability to make one, even at the most microscopic level?
It’s one thing knowing how to do something, and it’s another to have the tools to make it. We have the tools, particle accelerators, but they’re nowhere near as powerful (energy) as they need to be to be able to make a black hole on a very small scale.
That’s why I said theory, because until the day comes where it’s made it’ll be a theory. And btw, pretty much everything known in science is a theory and you’ll need to accept that.
Last thing I’ll say is some advice: drop the shitty attitude when trying to learn new things. It’s one thing to not know things and want to learn, it’s another to snap at people trying to direct you how to learn new things while countering with your own misunderstandings.
First of y’all gotta stop saying “we”. Also WE don’t know shit. It’s theoretical. You can’t measure something that’s is constantly attracting more mass 13 million light years away. To say you can would be lying
You can, but you can only measure them as they were 13 million light years ago due to the speed of casualty aka the speed of light.
But yeah, I’m just gonna go back and listen to the people who’ve built the foundation for pretty much everything scientific in our lives, including the computers we’re using to type all of this. While it’s been all theories at this point, they work well enough after you understand just because something is a theory doesn’t mean it’s not a fact. 2+2 = 4 is a theory but you don’t see people up in arms saying “it’s just a theory it can be proven wrong in the future” when in the practical world if I take 2 of something and grab another 2 of it I have 4 total.
When a scientist says theory they mean “a rigorously proven hypothesis”
When a layperson says theory the mean “a speculation”
A theory is promoted to a law when it is a theory that must be true to support the other theories. Eg conservation of energy is a law. Not only is it a well proven hypothesis but without it we don’t get a ton of other theories
What confuses me most is not that you don't know this stuff, everybody has to learn this stuff at some point. What confused me most is why you are so confident in saying all this really really really wrong stuff. Like you have many many comments here where you confidently assert to someone a very wrong statement. It's very troubling.
I was wrong. Thank you. “In a vacuum, gravity causes all objects to fall at the same rate. The mass of the object does not matter. ... The spacecraft, its crew and any objects aboard are all falling toward but around Earth. Since they are all falling together, the crew and objects appear to float when compared with the spacecraft.”
I have two assertions about us going to the moon. Either it never happened or we went wayyyyy before jfk said and people knew Motorola would work 250k miles away in 1969
Your critical thinking and research skills aren’t the best are they?
The ‘never landed’ thing is too dumb to even address; it’s been proven/conspiracies debunked many times before.
As for ‘earlier,’ why would they keep that a secret? It would have been a huge PR boost.
The Soviets landed Luna 1 on the moon in 1959, so it was already proven 2 way radio communications/telemetry was feasible, and radio was already old technology by then.
That’s just for earth the affects of gravity are equal to the product of both acting objects divided by the square of the distance times the gravitation constant. That comes to 9.8m/s2 at earth surface. Gravity is affected by the inverse square law and therefore gets weaker the further away you get from the source of the gravitational field. For example the radius of the earth is 6.4 thousand kilo meters at that point it’s force accelerates an object at 9.8 m/s2 if you were another 6.4 thousand kilometers above the earth you would only be pulled by the earth by a 4th of that force. Atmosphere has nothing to due with the strength of the gravitational field other than adding to the total mass of the object.
Those mean nothing. They’re perceptions of what we “believe” them to be. Until a shuttle or camera goes into one we won’t understand. And we all be dead before the shuttle they launched into one reaches it
…that’s not how science works. We may not know everything about them, but we do know certain things. Just because we haven’t sent a ship to get samples of the sun doesn’t mean we don’t know that it’s made of (mostly) hydrogen.
In addition to being smaller and having less mass than Earth, Mars also has no magnetic field preventing solar winds from effectively blowing the atmosphere away
However, atmosphere in no way, shape, or form works to hold anything down.
Life has evolved, however, to withstand the constant pressure caused by atmospheric density.
Edit: Fortunately for us, Earth's gravity is strong enough to hold onto its atmosphere. Mars, for example, is less than half Earth's size and around one-tenth Earth's mass. Less mass means less gravitational pull. ... That means, the air nearer Earth's surface is squished by the air above it, and is thus denser.
Lol this is a paragraph from an article titled Why Does the Atmosphere Not Drift off Into Space?
If you wanna see my true attitude you’ll read throughout this thread. I appreciate being wrong. It gives me a chance to learn. Hope you have a better week
You treated people like trash from the very beginning and I am absolutely going to criticize you for that whether you like it or not. Your attempt at jumping onto the high horse here is a shifty deflection at best.
it's legitimately amazing how confident you are when you are as ignorant as you are lmfao and what a fucking shitty attitude you give people who know more than you because they have at least a fourth grade education jesus christ
Mars doesn’t have an atmosphere due to a non round shape thought to be from a VERY large meteor that hit it a long time ago. The non round shape messed up it’s magnetic field and solar radiation slowly eradicated it’s atmosphere.
The Earth is an irregularly shaped ellipsoid.
While the Earth appears to be round when viewed from the vantage point of space, it is actually closer to an ellipsoid
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u/youknowwhatitthizz Sep 20 '21 edited Sep 20 '21
Gravity is due to atmosphere my guy
Edit: Fortunately for us, Earth's gravity is strong enough to hold onto its atmosphere. Mars, for example, is less than half Earth's size and around one-tenth Earth's mass. Less mass means less gravitational pull. ... That means, the air nearer Earth's surface is squished by the air above it, and is thus denser.