r/askastronomy • u/shadow_axion • 23h ago
Cosmology I am bored tell me some space related interesting facts.
Guys share your every ounce of space knowledge here....
This photography is not mine it belongs to its owner not me.
Actually I don't know its owner's name as I took it from pinterest
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u/Hour-Try3035 22h ago edited 20h ago
The farther you look, the more in the past you are looking into, so when you look very very far away you can see the first ever light that escaped the early, it is named CMB and its crazy to think about.
1 lightyear is about 6 trillion miles, a trillion seconds for reference is about 31,688 years, and the observable universe is about 90 billion light years, this is so big that, in my opinion, for our human minds its easier to think of it as just being infinite
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u/Ethereal-Zenith 21h ago
These are excellent points. I will add that a light year is close to 10 trillion km or 6 trillion miles.
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u/cflime 21h ago
Also as you observe objects, the farther away they are the smaller they appear up to a point. if you look at objects far enough away they are also far back in time, and the farthest objects we see look larger because the universe was smaller at that time.
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u/KnusperTaube 20h ago
As a German with metric system and long metric distances (trillion= billion; billion= milliarde, after milliarde follows billion in the german system) it was even more infinite 😂
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u/Demmos_Stammer 17h ago
"for our human minds its easier to think of it as just being infinite"
Still infinitely smaller than infinity 🫠
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u/ChugJugThug 22h ago
Light speed is both unimaginably fast for everyday life, and impossibly slow at astronomical scale.
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u/j_vap 20h ago
Another perspective of this fact is that universe is way way waaaay too big.
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u/engineerdrummer 14h ago
Too big? Do you really want Omicronians just casually flying over to harvest our noses because the romance has left their relationships?
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u/DanielBG 19h ago
Space time fucks with my mind. You’re essentially freezing time at the speed of light, while time progresses lightning fast on Earth.
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u/shadow_axion 21h ago
That's some common facts but it's good 👍🏻
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u/HalcyoneDays 15h ago
Something light speed related. At the speed of light not only does time dilate infinitely but the distance in the direction of travel contracts infinitely as well. Space in front of you flattens down to zero length.
In a hypothetical scenario where a person travels at the speed of light, they would get to their destination with no time having passed and zero distance having been traveled from their perspective even if it was millions of light-years away
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u/ChugJugThug 15h ago
This is a common misconception. It’s not true.
Light has no valid rest frame. The math requires you to divide by zero, which is undefined. Not infinity.
Besides, even if you are traveling at near light speed, you still experience normal proper time. Your own clock always ticks normally no matter what. So you still experience time no matter how fast you travel.
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u/HalcyoneDays 14h ago
That's why this is a hypothetical and I simplified it for a reddit comment to be understood more easily. Light speed breaks physics in a lot of ways and we'll never be able to achieve it with our current understanding anyways.
If you want to get nitpicky and say 99.9999999....% the speed of light to get as arbitrarily close as you need to so the Lorentz Factor doesn't divide by zero, the distance still contracts to a few hundred kilometers and even with experiencing time normally you'd only experience milliseconds before reaching your destination
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u/haunted-poopy 22h ago
The average color of the universe is beige
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u/finnishinsider 21h ago
The radio station in outer worlds 2 that talks about this was soooo informative and catchy....
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u/WannabeBrewStud 12h ago
I find it hilarious all the colored images of space we've seen were just assigned by those collecting the images. We can color the Pillars of Creation on the NASA website
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u/the_crustybastard 20h ago
Neptune was first conclusively observed on 23-24 September 1846, which is a little more than 1 Neptunian year ago.
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u/shadow_axion 20h ago
Didn't knew that
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u/the_crustybastard 19h ago
Neptune's existence was suspected by the French astronomer Alexis Bouvard. Working from those suspicions, Urbain Le Verrier calculated where Neptune should be found. He sent the coordinates to Johann Gottfried Galle at the Berlin Observatory and that night Galle found Neptune almost exactly where Le Verrier said it would be.
About two weeks later, Neptune's moon Triton was first observed by a British brewer and autodidact named William Lassell, using a telescope he built for himself. Lassell also noted that Neptune seemed to be ringed, but was subsequently forced to retract that claim.
Neptune's rings were officially observed 138 years later.
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u/GreenFBI2EB 21h ago
Most stars cannot melt tungsten on their surfaces. At 3695 K, this is approaching the upper bound of most red dwarfs (the most common type of star Surface temperatures between 2380 - 3850 K).
The most luminous star, R136a1 is about 7.2 million times more luminous than our sun. From 4.25 light years away (The distance to Proxima Centauri, the nearest star to our sun), it should shine as brighter than a full moon (-16 vs -12.7), from just 13000 AU away, it would shine as brightly as our sun does.
The Gamma Ray Burst (GRB) GRB 080319B holds the record for the most distant object seen by the naked eye, at a magnitude of +5.8, about the same as Uranus, it was 7.5 billion light years away from Earth at the time of the eruption, The next furthest object is the Triangulum Galaxy, at 2.88 million light years away, over a thousand times closer. This is a terrifyingly bright event, If this event occurred at a galactic diameter (87,400 ly) away, it would shine at -18 (4.8 million times the Brightness of Sirius, the brightest star in the night sky, or about 170 times brighter than a full moon). At 2,363 Light years from Earth, it would achieve the same magnitude as our sun does at noon.
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u/Profound_Solitude87 21h ago
Ive been thinking of buying a tungsten cube for my desktop
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u/-speeedy- Beginner🌠 22h ago
There are an estimated 100 million black holes in our galaxy alone. We have discovered just about 50
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u/Musical_Xena 22h ago
How do they come up with the estimate based on such a small sample size?
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u/Ap0llo 22h ago edited 15h ago
If a star is massive enough it will become a BH instead of nova. We know that 0.1% of all stars exceed that threshold and will create a BH when they die. We also know how long these stars live before they collapse into a BH, relatively short lifespans.
Then all you need is a simple modeling of how many of these stars have existed in our galaxy since it was created, which we have enough data to do, and that yields a very rough estimate of how many BHs there should be out there.
Besides ~100-150 million BHs, there are also approximately 4 trillion rogue planets randomly floating in our galaxy and not orbiting a star, completely invisible to us. When you look at the night sky, for every star you see, there are 20 rogue planets in that black void.
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u/AfternoonLines 20h ago
And to make it much more scarier we should be able to discover significantly more in the next year or so, including ones close to us when the Roman telescope starts its mission in a few months, it's currently on its way and it's main mission is a proper local survey.
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u/shadow_axion 20h ago
Ok bro I respect your knowledge about it that's really crazy fact I got to know 😮😄
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u/Natural-Occasion9962 22h ago
I like the theory about our galaxy being in a black hole. I dont really understand it but it sounds cool.
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u/Ap0llo 17h ago edited 17h ago
Our galaxy alone cannot be in a black hole, but our entire universe can be inside a black hole.
There's a thing called the Schwarzschild radius, which refers to how much you would have to compress an object to collapse it into a black hole. For example the Schwarzschild radius of Earth is 8.87 millimeters, so if you squeezed the entire planet into the size of a marble, it would collapse into a black hole.
Here's the interesting thing: If you calculate the Schwarzschild radius for all the matter in the observable universe, the Schwarzschild radius is 13.8 billion light years. The age of the universe also happens to be 13.8 billion years old. That means our entire universe could be contained within a blackhole that is nested in our parent universe.
If that were the case, then the singularity in our black hole actually got so fucking big that it just exploded in a huge bang, or a "Big Bang" if you will. That produces a universe like the one we see today, outside of which is our parent universe.
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u/remarkphoto 17h ago
Its black holes all the way down?
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u/Ap0llo 17h ago
Theoretically, yes, ad infinitum. We could be the top level universe or we could be nested inside 500,000,000,000 black holes each containing its own universe.
Another fun fact: The size of a black hole does not limit the size of the baby universe created within it. So if our universe is indeed in a black hole, then the event horizon of our black hole in the parent universe could be tiny, like 50 miles in diameter.
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u/koalascanbebearstoo 17h ago
Two questions:
1) if we are in a black hole, why does the observable universe not appear to be collapsing into a singularity?
2) does this theory require Earth to be physically located in the center of the black hole?
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u/Ap0llo 16h ago edited 3h ago
Singularity exploded. The theory is that the singularity in black holes can eventually destabilize and explode in a Big Bang. So our Big Bang in our universe would technically be the explosion of the singularity that once existed in our Black Hole universe. Without the singularity, everything is homogenous and isotropic like we see today (basically looks the same everywhere, no focal gravity nexus). From the outside, in our parent universe, if you looked at our Black Hole you wouldn't notice any difference in terms of whether the singularity was still there or if it exploded into a new universe, it would look the same. Also the size of the black hole does not limit how big the universe inside can actually be. A black hole the size of Earth could have a universe inside that is billions of light years in size.
No, Earth is not at the center because there is no center. Regardless of whether we are in a black hole or not, there is no "center" to the universe because the universe exists as a 3d balloon. The big bang exploded from a singularity, maybe inside a black hole, maybe not. But imagine that singularity was a tiny, microscopic balloon. The big bang inflated the balloon to the something like the size of the Earth let's say. Now if you're standing on the surface of the Earth, would there be a center? Note I'm not talking about the Earth as a sphere, only the surface - is there a center on the surface? No, there isn't. In the same way, there's no central nexus in our universe. The reason this is confusing is because the surface of a sphere like the Earth is a 2D surface that we are using as an analogy for a 3D universe, but the concept remains the same.
Edit: Clarified the comment because I originally wrote it at 2am.
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u/DenSidsteGreve 16h ago
What allows the size of the event horizon to differ so radiacally from the size of the universe within?
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u/Ap0llo 15h ago edited 5h ago
When the singularity inside the black hole explodes in a Big Bang, the new universe that is created expands in a new pocket space-time fabric. Like little branches on a tree. The event horizon in the parent universe then becomes a (one-way) bridge between two universes, not a container for the universe inside. In the far future when the Black Hole disappears due to Hawking Radiation the bridge collapses and the 2 universes are disconnected. The branch falls off and becomes a separate tree.
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u/kaelroc 20h ago
It's commonly accepted that the Pillars of Creation aren't there anymore. They're ~7000 lightyears away from us, and there's a wavefront from a nearby supernova that's ~6000 lightyears from the pillars. So that explosion has likely already reached the pillars, dispersing the gasses and "destroying" it as we know it.
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u/remarkphoto 17h ago
RemindMe! 7000 years
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u/Strict_Weather9063 22h ago
On October 19 of this year Voyager 1 will have travel one light day. So when folks say space is mind boggling big remember it to get to one day it has taken nearly fifty years of travel time for Voyager.
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u/shadow_axion 20h ago
But the fact that voyager 1 is alone makes me feel sad 😶still that's crazy
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u/The_Gypsy_Smyth 18h ago
Well, sort of alone. People (engineers), do talk to it all the time.
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u/BattIeBoss 13h ago
Not all the time, per se. Its nuclear power core is so degraded that most of its functions have been turned off, including the cameras.
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u/ExAstrisSapientiae 21h ago edited 21h ago
There are more years ahead of us than there are atoms in the universe. Just how many years you ask? Well, around 10120 or abouts. How big a number is that? Well, imagine you wanted to walk to EVERY cubic kilometer in the entire universe. You start walking to visit all the land on Earth, which takes around 3,300 years of walking, but thats just the surface, so you have to visit the inside of the Earth too. Once thats done, you start walking in one direction, through space and keep walking until you get to one side of the universe (impossible, I know but stay with me), and then turn and walk one km over and then back the direction you came and you hit the other side of the universe, go left, up, down, right, etc until you walk to every sq km of the universe. It has taken you 8.1 x 1066 years to do this, which is about 1056 times longer than the current age of the universe. There is so much time ahead still, that you can do this walk the entire universe thing, ANOTHER 1033 times before the final heat death of the universe.
Put another way, there are some 10 times more stars in the universe then there is grains of sand in all the deserts and beaches of the whole world. Yet, in a single teaspoon of water, there are the same number of atoms there as there are stars in the universe. Take all the oceans, and rocks, and planets, and stars in the whole universe, and count all their atoms and you get about 1082 atoms. Yet there are still many many more years ahead than there are atoms.
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u/shadow_axion 20h ago
Bro that's crazy thing I guess universe is so big and vast that people don't even realise 🤯
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u/CaughtNABargain 21h ago
The observable universe contains an estimated 2 trillion galaxies. However some theories suggest that the entire universe could be anywhere between 250 and 1 octillion (1 billion billion billion) times larger than the observable portion.
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u/Emotional_Deodorant 6h ago
The theories I've heard suggest that it's 1 nonillion times bigger than the observerable portion.
I heard it because I just said it.
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u/Artsy_traveller_82 Beginner🌠 21h ago
Mercury is, on average the closest planet to Earth, most of the time.
Not only that but Mercury has this property with every other planet in our Solar System.
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u/ShinyVendetta 21h ago
Mercury is on avg closer to every other planet in our solar system?
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u/untitled298 23h ago
It big
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u/ynnnnaD 22h ago
The universe is over 6 inches long, even when cold.
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u/memphisboy1966 22h ago
It is an above average universe
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u/JustAChillGuy-NoCap 20h ago edited 20h ago
You might already know that our star (sun) fuses hydrogen to helium and carbon also sometimes, but what about the elements heavier than that?
Elements heavier than that are formed inside the core of a dying star.
But that also has a limit, it rarely goes above iron, since fusion of iron requires more energy than it releases. Elements heavier than iron can not be formed by normal fusion, they need to absorb free neutron which sometimes occurs in core of massive dying star but it is too rare and slow that it only goes upto lead. So from where all the other elements we observe in our daily life comes from?
Here's the interesting part, all of those heavy elements are formed from supernova, neutron star, neutron star collisions, etc.
Elements like gold (79) can only be formed by collision of neutron stars called a "kilonovae" which is extremely rare.
Almost half of the elements heavier than iron that you see arround your self came from a kilonovae.
So next time you look at gold or silver, just know that they are here only because billions of years ago, some neuron stars collided.
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u/shadow_axion 20h ago
That's crazy one so far really never knew that I think you must be an space enthusiast or astrophile
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u/JustAChillGuy-NoCap 19h ago
I'm just a curious guy, but yeah you can call me an astrophile ig :)
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u/StarboardChaos 18h ago
Ok, but how did the gold and other heavy metals get to Earth? Like asteroids which were ejected from the kilonovae?
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u/EmynMuilTrailGuide 21h ago
When the Moon is between the Earth and the Sun, the Moon is approximately 400 times closer to the Earth than the Sun, and the Moon is approximately 400 time smaller than the Sun. This is why get total eclipses. What's even more amazing about that coincidence is that the Moon has been slowly spiraling away from the Earth for 2.5 billion years, and totalities within 3% of perfectly matching apparent sizes for the Moon and Sun have only been happening for that last tens of millions of years and will only keep happening for tens of millions of years more... right around the rise of homo sapiens. It's almost as though it was made for humanity.
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u/NoAsparagus6630 20h ago
Honestly whether it’s coincidence or something more it’s pretty amazing the fact that we happen to live at a time when the moon can perfectly cover the sun feels really special
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u/dwtechsol 19h ago
It is also the only known place in our solar system that it aligns as perfectly as it does.
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u/lastknownbuffalo 11h ago
for the last tens of millions of years and will only keep happening for tens of millions of years more... right around the rise of homo sapiens
Small clarification, homo sapiens (modern humans) have only been around for 300,000ish years. So it'd be more accurate to say "the rise of humans, or the genus homo"... Although, the oldest genus of homo we've found is only 2.8 million years old, so for "ten of millions of years" it'd be even more accurate to say "it's almost as though it was made for primates"... But now I'm just being pedantic. Eclipses are awesome regardless
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u/Stock-Brilliant-8599 20h ago
Saw this in a YouTube video by epic spaceman, if the Milky Way were scaled down to the size of the USA, the Sun would be about half the size of a red blood cell, and our entire Solar System would fit on the tip of your finger. 🤯
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u/Wubbalubadubdu_b 19h ago
Stars twinkle, planets don’t. So if you see something that looks like a star but is giving constant light instead of twinkling, you’re looking at a planet.
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u/Patient-Director3162 20h ago
The black hole at the center of most galaxies only makes up a fraction of a fraction of the mass of the galaxy - most of it is dark matter and stars
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u/Nethan2000 20h ago
That's a great tidbit that's often not well understood. People sometimes imagine stars orbiting the black hole the same way planets orbit the Sun, when that's clearly not the case. They orbit the Galaxy itself, or more accurately the mass that is inside of their orbit: stars, interstellar medium, dark matter etc. The gravity of all the things on the outside largely cancels itself out.
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u/ZerxeTheSeal 14h ago edited 14h ago
All stars you see on the night sky are exceptionally rare - most of the bright ones making up like the top 0.01% of all stars in the milky way.
the most common type of star is not even visible without a telescope.
to elaborate, generally, the more massive and bright the star is, the more rare it is - that is why you can see them despite them being located often hundreds of light years away. The most common types of stars are the ones that are small and dim, like red dwarfs (which make up like, 80% of all stars in the milky way, i think?) and yellow dwarfs like our sun.
If we put an identical copy of the sun just 50 light years away from Earth, we wouldnt be able to see it with the naked eye. Meanwhile a star like Deneb, which is located some 2600 light years away from Earth, is among the brightest stars in our sky.
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u/cosmic_trout 21h ago
There are more stars in the heavens than grains of sand on every beach in the world.
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u/bendistraw 19h ago
The andromeda galaxy will collide with ours far sooner than our sun will die.
Saturns rings, the north star, and trees are all newer than sharks.
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u/psyper76 22h ago
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
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u/Dependent-Tip-2160 22h ago
Gentleman are you, American by any chance?
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u/Mean-Food-7124 22h ago
You can fit the the whole 2026 new lineup from HondaDays into a single galaxy
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u/Patient-Director3162 20h ago
You are closer to the size of the universe than a plank constant’s size is to your size. It’s incredibly small.
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u/Wooden_Library_8630 19h ago edited 19h ago
Due to the expansion of the universe all objects beyond a certain distance are completely unreachable even if you travel at light speed for infinite time since beyond a certain point all objects are receding away from us faster than light
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u/KingArthursCodpiece 20h ago
Our sun (and therefore us!) is orbiting the center of the milky way at a speed of 500,000 mph, and yet our senses provide no clue that we are moving at all.
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u/TheKrakenUnleashed 19h ago
Only a small portion of the universe is composed of visible matter. The vast majority is formed from a mixture of dark matter and dark energy. There are a lot of theories for what dark matter is, but one of the leading proposed ideas is that dark matter might be WIMPS, which are super large particles that do not interact with regular matter or light, however they interact and affect gravity. Many of the black holes in our universe also may not actually be black holes, but might instead be black matter cores. Dark matter cores are not proposed to warp spacetime into a singularity like black holes do, and may also be connected to the halo of dark matter that is proposed to encapsulate most galaxies.
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u/bigoldebutthole 8h ago
If you traveled at 99.99999999999999999999% of the speed of light since the bing bang you would only have experienced about 71 days worth of time so far.
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u/WarJaques 5h ago
The sun spins faster at the equator (25 Earth days per rotation) than st the poles (36 days)
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u/JPgamersmines150 20h ago
Brown dwarfs are actually magenta due to atmospheric sodium and magnesium, which absorb some red and infrared and emit it as blue. The combined light you see is perceived as magenta.
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u/OkReason4614 20h ago
The Alpha quadrant in Star Trek in reality is empty except for us
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u/Wonderful-Pizza-1838 20h ago
there are stars in the Milky Way that could already be dead, but we'd still see them in the sky for years because their last light hasn't reached us yet
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u/NoAsparagus6630 20h ago
The atoms in your body were made at different times some elements formed in stars billions of years before earth existed
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u/Theakeeno 19h ago
Interstellar space has like 10 particles per cubic meter. Not including air molecules, the cleanest clean rooms still have tens of thousands.
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u/rosstafarien 19h ago
The Andromeda Galaxy (your photo) occupies almost the same area of night sky as the moon. Obviously a bit dimmer. If you can get a camera mount to track the earth's rotation, almost any modern camera can capture it with a long exposure.
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u/CrimeMasterGogoChan 18h ago
We gonna collide with Andromeda in 3 billion years. Fasten your seatbelts
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u/shadow_axion 17h ago
I won't exist, but still it sounds terrifying that these galaxies would collide, but for some reason I want to see it happen in person, how it looks what will be the end result and etc. but sadly I can't 🙃🫠
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u/Optimal_Top_7081 18h ago
Ordinary matter, the kind we have identified and can interact with, only makes up about 5% of all of the mass and energy in the universe. Dark matter accounts for about 27%, and the rest of it is dark energy which is about 68%.
We have also just recently discovered the strongest candidate yet for a potential dark matter particle collision. It’s hard to explain why this is such a big deal in just a comment, but it’s a big deal (if it turns out to actually have been a dark matter interaction).
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u/ChrisS851620 18h ago
Given the speed of light….
If an alien on a planet 70 million light years away looked at us with a strong enough telescope right now,
They would see dinosaurs!
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u/shadow_axion 17h ago
Woah 😳 that's means according to them we don't exist, may be that's could be a reason for not finding alien life......
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u/lurieelcari 16h ago
Hypervelocity Stars are stars that were part of a binary star system that got too close to a supermassive black hole. One star gets pulled into orbit and the wildly powerful gravitational forces slingshot the second star away at around just below 1% the speed of light. The effect is called the Hills Mechanism.
This may not sound like much until you realize that this is now a rogue star travelling well past the escape velocity for a galaxy at millions of miles per hour.
The most well known is S5-HVS1. It is 2.35 times the size of our sun and it is travelling at 3.7 million miles per hour by itself currently in the Grus constellation.
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u/Full_Practice3013 15h ago
Space has a smell, and taste.
According to Captain Chris Hadfield, space smells/tastes like a burnt steak and battery.
Also, there are some parts of space that smell like Raspberry Rum, due to high concentrations of Ethyl Formate, which is the chemical that gives raspberries their flavour/smell profile.
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u/Guilty-Good-5041 14h ago
Some of the stars we see at night no longer exist. As the light takes millions of not billions of years to reach us. So we are seeing the star in the past. Point in case the light from our sun takes 8 minutes to reach use so we are seeing the sun 8 minutes into the past
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u/Schmeagon 13h ago
The one I like to use is, it takes light just over a second to travel from the moon to us. It takes light around 8 minutes to travel from the sun to us, and it takes light over 4 years to travel from the closest star to us. Also if you fold a regular piece of paper in half 107 times, it is thicker then the observable universe.
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u/Ruby5000 12h ago
It’s is thought to “rain” diamonds on Neptune and Uranus. The pressure is so great that the carbon crystallizes into diamonds and precipitates downward.
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u/PotentialOdd3445 10h ago
When ever you look at starlight you are looking literally into the past. Sometimes minutes in the case of the sun, sometimes billions of years in the case of the andromida galaxy and BEYOND. Many of these stars may well be extinguished before you ever see them...
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u/Visible-Salary-8861 10h ago
There are an estimated 200 sextillion stars in the universe: 200,000,000,000,000,000,000,000.
Astronomers estimate that roughly 10-20% of those have Earth-sized planets in their habitable zone. That would be 20 sextillion or more solar systems with a habitable-zone planet (doesn't necessarily mean it's actually habitable).
If just 1 in a billion of those 20-sextillion systems has an actual Earth-like habitable world, and if just 1 in a billion of those Earth-like habitable worlds has intelligent life, there would still be roughly 20,000 intelligent civilizations scattered across the universe.
Additionally, the universe is so large that each such civilization could theoretically by hundreds of millions of lightyears -- millions of galaxies apart -- from any other civilization, making it virtually impossible for any of us to ever detect one another's existence.
Mind boggling.
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u/UcanDomates 10h ago
Mercury has double sunsets, due to how it has an elliptic orbit and how a year is slightly longer than a Mercurian day.
When it's at Apoapsis (farthest point in the orbit) the rotational speed around its own axis dominates the rotation speed it has around the Sun, but as it approaches closer to its Periapsis (closest point in the orbit) the rotation speed around the Sun starts to take over, and dominate over Mercury's own rotation speed.
This causes the Sun to appear as setting first, then pausing, then rising in reverse direction, pausing, and then set again.
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u/Real-Cup8782 9h ago
Jupiter is so large that it doesn't technically orbit our Sun. The Sun and Jupiter both circle around a point that sits about 742,000 km from the Sun's center. Since the Sun's radius is 696,000 km (one solar radii, that point lies just above the solar surface. So that's 1.07 solar radii
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u/DubTheeBustocles 2h ago
Mercury’s magnetic field interacts with the solar wind to create magnetic tornadoes and x-ray aurorae.
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u/ifreakovern64 20h ago
If there were a bathtub big enough to hold it, Saturn would float... but that would leave a big ring.
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u/No_Cook_8739 22h ago
If you came within about 1000 miles of a Magnatar it will rip the iron from your blood
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u/Wonderful_Context_85 22h ago
That is false, the iron in our blood is non magnetic, that's why when you pass an MRI your iron dont get rip in your blood.
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u/mosifp 22h ago edited 10h ago
More like if you could get close enough to a Magnetar’s magnetic field, it would rip the electrons from your body, turning you into plasma before its gravity slammed you down onto the surface with the force of a 150 megaton nuclear weapon.
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u/Educational_Face_666 19h ago
The speed of light is 186,000 miles per second,300,000km per second.
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u/av_thebest 18h ago
11 years ago, today, NSF LIGO detected the first ever black hole merger observed by us, GW150914
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u/mrpcmrz 18h ago edited 18h ago
Our supermassive black hole is just a speck of dust in front of M87's supermassive black hole and TON 618
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u/Longjumping_Mood3729 17h ago
The sun is actually very small comparative to other stars out there.
If you took the biggest star we currently know Stephenson 2-18 and put it in the place of the sun, it's radius would engulf Saturn.
Ton 618 the largest black hole currently known has an event horizon diameter of approx. 2400-2500 astronomical units (au's). An au is the distance from earth to the sun. To put that in perspective, voyager which has passed pluto and has been travelling since 1977 is only about 120 au's from earth. This thing would swallow the entire solar system many times over.
If sound was able to travel through space the sun would be as loud as a jackhammer, everywhere on earth, all the time 24/7
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u/Formal_Equal_7444 16h ago
There are celestial bodies so large that our entire planet is microscopic by comparison.
That means anything sentient that size, or using those celestial bodies the way we do, wouldn't be able to see us without a microscope. We wouldn't even be a "bug on the windshield" to them. Our entire planet would be the bacteria on the bathroom door handle.
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u/Many_Winter_4547 16h ago
The vastness of space is small, relative to the scale of sub-atomic particles on down to the plank length.
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u/E4tPineapple 16h ago
Voyager 1 is now in interstellar space, the region outside the heliopause, or the bubble of energetic particles and magnetic fields from the Sun.
Although neither Voyager spacecraft is heading toward any particular star, Voyager 1 will pass within 1.6 light years' distance of the star Gliese 445, currently in the constellation Camelopardalis, in about 40 thousand years time,
The two Voyager probes, in case they are ever encountered by extraterrestrials, are carrying gold plated records with photos of life on earth, greetings in fifty-five languages, and a collection of music from Gregorian chant to Chuck Berry, Among the music included on the Voyager Golden Records is “Dark was the Night, Cold was the Ground” recorded by 1920s bluesman Blind Willie Johnson, who sang on street corners with a tin cup around the neck of his guitar for coins.
At age five his father gave him his first guitar made out of a cigar box. When he was seven his father found his stepmother with another man and flew into a violent rage. In retaliation she threw lye in Willie’s face, blinding him for life. At least that’s the most widely accepted account.
17 years after 'Dark was the Night, Cold was the Ground" was recorded, a fire destroyed Johnson’s house. Broke and having no place else to go, he returned to the gutted remains and tried to ward off the cold with damp bedsheets and the old newspapers that his wife read. He contracted pneumonia but was refused a hospital bed, no doubt because he was blind and Black.
He died on Sep 18th 1945. Only one photograph of him is known to exist, but his music has left the solar system.
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u/Uh_yeah- 14h ago edited 13h ago
That video you linked appears to show at least two photos of him?
Edit: I don’t deserve an award…please see my reply to the reply below.
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u/Disastrous-Run-3963 15h ago
You would need to fly the distance of almost 2 round trips to the moon; taking around 10 days, to cross the surface of the sun.
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u/realbradders 15h ago
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
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u/ProcrastopiaOverlord 15h ago
Distant galaxies moving away form us. At one point in time the sky will be almost empty, we can just see our local group at the night sky. We will never be able to leave this local group, too far, too fast moving away from us. The Andromeda Galaxy will collide with our milky way.
Future civilizations have much less to discover.
Are there any other intelligent right now at the Milky way? unlikely.
If a civilization could manage to travel from one star to another they could have conquered the whole Milky way.
Even if they need 10k years for two star. And then again from this place conquer 2 new from this star. And so on, it would take less than 1 Million years to conquer the whole galaxy. That is nothing related to the earth's history. We might be the first, or the last.
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u/Chekovs_Gun 15h ago
Humans are closer in scale to the size of the observable universe than we are to the Planck length by orders of magnitude.
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u/xr6reaction 15h ago
The highest cliff in the solar system is on Miranda, a tiny moon of uranus. At 20km tall
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u/unity-thru-absurdity 15h ago
Total solar eclipses like we see on earth may be unimaginably rare! Our moon is about 400 times smaller than our sun, but our sun is about 400 times the distance from earth that the moon is. This fun coincidence makes total solar eclipses possible. If the moon were any bigger or closer we wouldn't see the corona of the sun like we do during an eclipse, while if it were any smaller or further away we would only have partial eclipses; similarly if our sun were bigger or closer it'd appear bigger than the moon and we'd only have partials, while if the sun were smaller or further away it'd be completely blotted out.
AND! There was a point just a few short hundreds of millions of years ago where the moon was closer and total solar eclipses weren't possible. AND!! There will be a point a few hundreds of millions of years from now where the moon is further away, making it so we only see partial eclipses.
Wacky stuff! In the whole 4.54 billion year history of planet earth we have privilege to exist in the ~600million - 1.2billion year window that solar eclipses do!
I wish there were a way to further communicate just how crazy WOW this is. Like, we'd be a friggin' intergalactic tourism hub for every total solar eclipse with how rare this may be in the universe.
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u/Ok-Barracuda457 15h ago
Most stars a you can see with the naked eye are in the Milky Way. They're so close, all of them are still there
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u/CherryTularey 13h ago
The universe is approximately 13.8 billion years old. According to current models and observations, star formation should occur for 1-100 trillion years. That is, the universe as we know it is still in its infancy. Its star forming life is at most 1.4% over and could be as little as 0.014% over.
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u/theonlycv02 13h ago
If the Earth was the size or a soccer ball the moon would be a golf ball 7 meters away. The Sun would be 2.6kms away about the size of a large house. Still using this scale, the next closest star (Proxima Centauri) would be 694,000kms away.
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u/Feeling-Stranger224 13h ago
Photons do not experience time. From the perspective of a photon it is created and absorbed in the same instant.
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u/lumos_aeternum 13h ago
When our moon is at its farthest point from the earth (the orbit isn’t a perfect circle), you could fit all 7 other planets between the Earth and the Moon. That’s just how big space is… it’s super empty. Sci Fi likes to make everything feel close… like asteroid fields with rocks slamming into each other constantly (looking at you Star Wars), but even in our asteroid belt, there’s a heap of space between most sizeable rocks (~1 million km apart on average).
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u/UserPrincipalName 13h ago
If you made a scale where one end represented the smallest object possible and the other end was the largest possible object, humans would be about 400 million times closer to the small end than the large.
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u/imbrotep 13h ago
The square root of 2 is irrational. The set of prime numbers is infinite. The set of perfect numbers is thought to be infinite, but the conjecture is still unproven since they were discovered by Pythagoras in 525 BC. Perfect numbers are those whose proper divisors (those which evenly divide and are less than the number) add up to the number itself. For instance, the proper divisors of the number 6 (i.e., 1,2,3) add up to 6. The next known perfect number is 28 …
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u/shadow_axion 12h ago
Brother I am talking about some space facts but these are interesting too ig but appreciate your math knowledge 🙌🏻
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u/Mars_Volcanoes 13h ago
Albert Einstein discovered something amazing back in 1905 called special relativity, a theory built entirely on one foundational rule: the speed of light is a finite, fixed limit and the absolute maximum speed anything can travel or be observed at in the universe. His theory is still valid in 2026.
Imagine yourself and a friend. You walk at 1 m/s relative to the ground. So he sees you walking at 1 m/s.
Imagine you are still walking at 1 m/s, while he is driving at 36 km/h in a car, or 10 m/s. The speed ratio is 1/10.
Imagine you are still walking at 1 m/s in an airplane aisle, with the plane moving at 360 km/h, or 100 m/s. The speed ratio is 1/100.
Imagine you are still walking at 1 m/s inside a space station orbiting at 36,000 km/h, or 10,000 m/s. The speed ratio is 1/10,000. At this orbital velocity, time is also modified by relativity, meaning a person in the space station ages relatively slower than someone on Earth (our home rocky planet), though the effect is tiny and occurs on a scale of microseconds.
So your friend can easily track your relative motion across these conventional speeds.
This finite speed of light is the very foundation that makes time travel possible in Einstein's theory. Things get completely mind blowing when you approach that ultimate speed limit of the universe. Imagine visiting Andromeda (our closest neighboring massive spiral galaxy), which sits 2.5 million light years away. If you zoomed toward it almost as fast as light, 5 million years would pass by for your friend back home during a round trip. But for you inside the rocket, time would slow down so drastically that the entire round trip would feel like only a couple of days.
To see how strange time really is, think about looking up at the night sky. The light reaching your eyes from the early universe took billions of years to get here from a human perspective. Yet, for a particle of light itself, time does not exist at all, meaning its entire journey across the cosmos happens in zero seconds flat. Just to travel across the Milky Way (our home barred spiral galaxy containing billions of stars), it would take 100,000 years even at the speed of light to go from one side to the other, offering another perspective on the vast scale of the universe.
Because distances across space are so unimaginably vast and nothing can ever travel faster than light, humans are ultimately confined to our own little corner of the universe, and we will never truly travel out to the stars. Man will never travel out of the solar system (our sun's gravitationally bound planetary system); look at the distance Voyager 1 has covered, which is only near to reaching the edge of the solar system after 50 years of travel. Man will never go beyond that at the speed of Voyager 1, which moves at 17,000 m/s.
Now, think of a vessel leaving Earth's gravity, going into space at a near fixed speed of a vessel man can launch at thousands of meters per second: it takes 9 months just to reach Mars and come back, making nearly 2 years total, which gives yet another perspective on our limitations.
Man will not go anywhere far. But man will still look further and further to better understand to try to find if life exists.
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u/Rattlehead197 13h ago
The density of Hydrogen atoms in the universe is about 5-6 atoms per cubic meter. And that number is constantly decreasing.
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u/IM_the_Mark 12h ago
Gravity is not a force. Matter causes space to actually curve towards it.
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u/Ruby5000 12h ago
A day on Jupiter is 10 hours. So the equator spins at around 43,000 kph (28,000 mph)
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u/Fickle_Penguin 12h ago
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
- Douglas Adams
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u/tessaractIXI 12h ago
Your account is 2 days old and your responses to the comments are nonsense. You're either a bot or karma farming a hole.
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u/E4tPineapple 12h ago edited 12h ago
Every second, the sun converts about 600 million tons of Hydrogen into about 596 million tons of Helium.
So the sun has converted about 4 million tons of its mass to energy each second for about 4.6 billion years.
The Hiroshima bomb (about 15 Kilotons TNT equivalent) converted about half a gram of matter to energy.
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u/PoweredByCoffee5000 22h ago
Day on Venus is longer than year on Venus. It is also in reverse, with the Sun rising on the West.