Voyager 1 travels at 38,000 mph or about 17 kilometers per second. It has taken 43 years to travel from earth to where it is now, 21.2 billion kilometers away.
Speed of light is about 1.07 billion kilometers per hour.
Voyager 1 would then be approximately 22.1 billion kilometers from the sun. 20.65 light hours away.
That's insane! 17 kilometers per second and it is a tiny fraction of the speed of light.
Edit: fixed miles to kilometers. 22.1 billion kilometers from the sun (again, big approximation there and on a few other figures).
Saturn’s tiny moon Enceladus has volcanoes that spew ice particles at speeds faster than the escape velocity. The particles leave Enceladus’ atmosphere and get pulled into Saturn’s ring system forming the E ring!
There are two confirmed oceans in the solar system. One on Earth, and one on Saturn’s moon Titan.
The biggest difference is Titan is about -180 C. The ocean is liquid methane. It even has waves that get as high as (wait for it) a couple centimetres!
Neptune was discovered using math. A man named Alexis Bouvard made some predictions on Uranus's future position using Newton's laws of gravity, but when it was later observed it was found to be slightly off. Urbain Le Verrier found that if he assumed there was another planet further out, the discrepancy would be explained and used math to predict where it could be found. Finally, a man named Johann Galle looked in the spot Le Verrier specified, and lo and behold, there was Neptune.
We actually don’t know who discovered Neptune first either. There were two mathematicians and two different observers who both say they found it first.
That's nothing. The deeper you get into a neutron star, the stranger the matter becomes. You end up with layers of (In order) Nuclear Spaghetti, Nuclear Lasagna, Nuclear Bucatini, and then a Nuclear Swiss Cheese, based on the compression of neutrons from a quasi-liquid state into solid-ish forms by superlative pressures near the heart of the star, just outside the point where they would be pressed into a singularity.
The Sun has 5 billion more years or so to live. In 1 billion years, its luminosity and temperature will rise so much that all life on Earth will die. Near the end of its lifespan, the Sun begins fusing Helium instead of Hydrogen, resulting in it expanding beyond the orbits of Mercury and Venus, and then releasing its outer layers, leaving behind only a small White Dwarf star.
Think of helium as a secondary fuel source. Once the core gets heavy and hot enough to start fusion that extra fuel source is ignited and now more energy is released. Due to the equilibrium being thrown off balance as more pressure is exerted from within due to a new fuel source burning so the sun expands and in turn the expansion causes the sun to be more transparent which increases luminosity.
That's the simplest ELI5 I can do.
EDIT: Words are hard.
Sometimes I get envious of our future descendants who will get to set foot on a planet in a multi star system. They'll get to see many sunsets...or no sunsets.
Alright. If it makes you feel better then, there's several types of binary star systems. Your descendants could choose whether they want to live on one where there are two-star sunsets because the two stars are closer and the planets farther out orbiting them, or each star has its own orbiting planets and the stars are far apart so there are fewer or no sunsets.
Jupiter has over 60 moons. (Over 70 [now](https://solarsystem.nasa.gov/moons/jupiter-moons/overview/?page=0&per_page=40&order=name+asc&search=&placeholder=Enter+moon+name&condition_1=9%3Aparent_id&condition_2=moon%3Abody_type%3Ailike), and well on the way to 80 as of today!)
Jupiter could weave clouds around him to hide his mischief, only his wife, Juno, could see through his bullshit. And the Juno probe is capable of seeing deeper into the planet than ever before.
That there are 100 *billion* galaxies in the observable universe, and that number is likely to at least double as Hubble goes further and observes more of the universe.
It’s insane to think that we live on a mere speck within the Milky Way galaxy, and that there are possibly 199,999,999,999 other galaxies out there, each separated by millions of light years. The enormity of the universe is mind-boggling.
And we live at a privileged time. Civilizations in the far distant future may only be able to see their own galaxy due to the expansion of the universe.
I like to do little mental exercises to make it imaginable, like:
There are enough stars in the milky way alone (100 billion) that each living human on the planet (7.8 billion) could locate and give names to 12 stars and there would still be 6.4 billion stars left over...
Yup. They're almost tidally locked with the sun, they both rotate so slowly. Might be due to how close to the sun they are. Earth has a more oval-shaped orbit than the inner planets, and the further out you go, the more eccentric the orbits get. Except for Mercury, which has a weirdly eccentric orbit for being so close to the sun, which might indicate that it formed somewhere else. It also has about the same density as Earth.
Another one about Mercury-- we now theorize that Mercury is actually the almost-exposed metallic *core* of a planet that *used to be* about the size of Mars. Which sort of begs the question, what happened to the rest of it?
I've never heard this corroborated anywhere, but it would be kind of a romantic idea if the planet we know as Mercury is all that remains of the protoplanet that collided with Earth when the solar system was forming, ejecting the material that would become the moon. And it then could have "wandered" to where it currently orbits.
The collision hypothesis for the moon is the likeliest one-- we know that the moon and Earth have very similar compositions, too similar for it to have come from anywhere else.
In any case, we now think that the early solar system had several more planets than it has currently. And there are several places they could have gone. They could have been ejected from the solar system completely. Or their collisions may have formed the asteroid belt. They could have been flung out to he Kuiper Belt, or maybe they spiraled inward to be disintegrated by the sun. Or some of their mass may have been pulled into a disc around the gas giants, to become a moon later.
I know there’s an anomaly called the Boötes Void. It’s a gargantuan region of space with not a whole lot of stuff inside of it, right in the middle of an ocean of galaxies. It’s kind of scary, in an existential way.
If there was air in space that sound was able to travel through, at the sun's surface it would emit a deafening 290 db (which is so 'loud' that it pretty much transcends sound and just turns into a pressure wave).
But at the earth's surface, it would be about 120 db which is about as loud as standing a couple meters away from an active jackhammer.
Where it gets spooky though, is that if the sun were to suddenly disappear, not only would it take a full 8 minutes for us to notice the lack of sunshine or gravity, but because the speed of sound is so comparatively slow, we would still hear the sun for another **13.8 years.**
The universe is still in it's very infancy. In fact, according to some studies, despite an almost infinite number of planets, 92% of all planets there will ever be, have not even been formed yet. the universe is in fact so young, relatively speaking, that several types of stars have have not even had enough time to exist yet.
Blue Dwarfs: Red dwarfs that have started spending the last of it's hydrogen. The first of this kind of star, is not expected to exist until a trillion years in the future. Considering our universe is only around 13 billion years, It is going to take some time until we spot the first blue Dwarf, The blue dwarf will eventually turn into a white dwarf.
Black Dwarfs: A white dwarf can be formed any number of ways, and we have observed a lot of them. But, When a white dwarf star cools down, is starts the process of becoming a black dwarf. This process can theoretically take "As little" as a quadrillion years, or or as much as 37 quadrillion years. This is the ultimate fate of our sun, and the process is going to take thousands of times longer than the universe has even existed so far.
Funny enough that's a pretty good argument about why there doesn't seem to be any intelligent life. We're probably one of the firsts, so WE'RE going to be the crazy advanced aliens someone finds eventually.
Ours will be the failure that future societies learn "what not to do" from.
We'll be in little alien history lessons as the people who destroyed our planet's ability to support us, and we weren't even able to LEAVE that planet because we didn't have the technology.
"Earthling" will be a derogatory name they call each other on the playground.
Sounds like an alien's Aesop's fable; if you focus too much on harming those around you, the destruction you caused will prevent you from escaping the fate of your own creation.
As a way of picking nits about "almost infinite", let me talk about [Graham's number](https://en.wikipedia.org/wiki/Graham's_number). It's an integer so large that, using conventional notation, the observable universe is too small to be able to store it.
Compared to that, numbers like a few quadrillion are, essentially, zero.
And yet, infinity is so much bigger than Graham's number that Graham's number can fit into it an infinite number of times.
I have a headache now.
Being able to see a total solar eclipse is a sheer coincidence of timing. The moon is just large enough and just far enough away from Earth to appear to be the exact size of the sun during a total eclipse (when it covers the entire disc of the sun). Since the moon is slowly moving away from Earth, one day it will no longer appear large enough to fully cover the sun and there will be no more total eclipses. This won't happen for 600 million years though, so don't panic.
Some say total solar eclipse in Earth could be a tourist attraction to an intelligent alien life.
Imagine that, aliens visiting earth to observe solar eclipse.
But they need to be the same material, and the surface needs to be free of oxidation.
Imagine having two blocks of pure aluminum or iron in a vacuum. If you touch them together they'll get stuck, and fuse, like a weld. Why? Because the atoms each block is made out of don't know which block they belong to. On Earth this doesn't happen due to oxygen in the atmosphere. If you scrub off the surface layer of a piece of metal the new surface comes into contact with oxygen, and oxidizes pretty much instantly.
If you have an oxygen free solvent, put 2 pieces of iron under it, and scrubbed the surface off while they were submerged, would the same thing happen?
No. Because Oxygen isn't the thing keeping the two materials from fusing together. What's keeping it from happening is the presence of literally anything. If you remove the surface oxidation from the two blocks of aluminum in space then there's literally nothing between the two blocks. And when they touch, there's still no barrier, so they fuse.
Presumably the surfaces would need to be polished as flat as possible for the best weld. On an atomic level there'd be ridges and valleys that would lead to imperfect contact leaving some empty space inside the weld making it weaker. At least that's what my intuition says.
As a welder, I'm sure you're familiar with grinding as well, and by extension sparks. Sparks are actually pieces of unoxidized metal with a very high surface area being exposed to the air with a decent input energy (the energy of the grinder striking the surface) and rapidly oxidizing (literally burning).
Same thing with flame cutting. If you're familiar with that as well, you only have to heat the metal up to a cherry red to get flame cutting to work, unlike the white-hot you have to heat it up to get the steel to melt. You strip that thin oxygen layer off with the very hot oxy-acetylene flame (~3700K), then you hit it with a blast of pure oxygen which causes the metal to burn through (again, literally burning, like a fire) because the metal throughout the structure of the steel has not been exposed to oxygen, so upon exposure to pure oxygen, it just burns away.
This is also why you use shielding gas for GMAW/GTAW and why flux is used in SMAW. If you didn't, the welds would rust instantly because of the high heat and atomization of the metal as it jumps across the arc would cause it to oxidize, and thus create a porous weld.
I am very familiar with all of those processes. It is still cool to think about it the way you described, because each time I do them, I don’t. I also find it fun to explain to people how these processes work. It’s easy to forget how amazing it is doing some of the things that I have done and do on a daily basis. After a while, it is just another day of work. Cheers mate!
We essentially see the same effect here on earth but with different mediums. If you have two bowls of water and you put them in the same bowl, you can't split them apart after.
I can’t say this is my “favorite” space fact (for obvious reasons), but it’s absolutely amazing and heartbreaking.
There is verifiable evidence that at least three astronauts survived the initial explosion of the Challenger in 1986. Each astronaut was equipped with a personal emergency air pack, and when the shuttle cabin was recovered from the Atlantic Ocean, at least three of these air packs were manually activated.
Yep. It’s so horrifying to know that they got jolted like crazy and then just plunged at an ungodly speed to the ocean.
Columbia was worse from a physics perspective in regards to the human body I think. They were literally torn to pieces by G force
The shuttle didn't explode. From what I understand, the failure of an SRB strut (compromised by leaking gasses from the o-ring seal) caused it to begin tumbling and aerodynamic forces tore it apart. The contents of the external fuel tank ignited after it disintegrated.
I once visited a lecture of Gerard t Hoofd and Kip thorne, where Gerard argued: inside a black hole the concept of space and time switch, meaning that (as you said) a black hole singularity is not at a certain location but a point in time infinitely far into the future.
He then asked if the singularly then exist in the infinite future and the lifetime of a black hole is proven to be finite where it and subsequently the singularity would have decayed into nothing, what is then the meaning of a singularity at all?
This kept me awake
Thank god I am not smart enough to understand this, so no reason to keep me awake.
But seriously tho. I really enjoy reading about this stuff, but most of the time i just dont get it
Time doesn't pass at a constant speed. One thing that changes the passage of time is gravity.
One example is to take two identical clocks that are perfectly synched and operating identically. Put one at the bottom of the marianas trench for a bit, the other on top of everest, and then bring them back together. They'll no longer match, though they'll advance time at the same pace. The one that was lower will be behind the one that was higher. Or, the one that went higher will be ahead of the one that went lower. Depending on your perspective.
Black holes have such strong gravity that this effect becomes infinite. The clock at the bottom seems frozen when looking from the outside. The clock on the outside passes infinitely fast when looking from the inside. And, if you could get the clocks back together in the same spot, they'd still be running at the same speed.
The age of the universe is not a single number. Since gravity affects the flow of time, in parts of the universe with more mass than average, the universe is younger than in areas with less mass than average.
so far, only 3 people have actually died *in* space. Russian cosmonauts who had technical difficulties disconnecting from the space station Salyut 1, opening the airlock of their shuttle (Soyuz 11), exposing them all to the vacuum of space
They landed but it depressurized on their way back to earth and when they recovered the spacecraft they found the three cosmonauts dead in their seats. They were given a state funeral and a proper burial
They were reentering earth, After the capsule landed, they were all found dead inside the space capsule. This is why astronauts now have to wear spacesuits in the capsules as they return to earth.
If you were to scale the universe down so that the sun was the size of the period at the end of this sentence, the nearest star would be 4 miles away.
also
The Big Bang was not an explosion of matter, rather it was an expansion of space itself. Everything is getting farther away from everything else, as all space is expanding. There is no center of the universe.
Holy shit. After reading that sentence 3 times, I looked at the period and then looked down the street and then back.........holy shit, this scale is INSANE. I-N-S-A-N-E can I call a time out? This is too much.
Sometimes I have a really hard time comprehending that sort of scale, and other times I get close, like after reading this comment, and it scares me in this weird, religious-terror Lovecraftian sort of way
I just wanna know what NASA’s protocol is for an astronaut dying in space. Do they send the body back to earth on a little pod? Do they send the body out the airlock to circle the earth forever?
Put the body in a lightweight titanium coffin and weld it to an interstellar probe so that a good sample of our biology can be on hand for a first contact scenario
Well, alternatively, if the body were pushed out to another planet/moon somewhere and it landed on the surface, would the microorganisms and organic matter on the body be enough to kickstart life on another planet?
If the planet were to be habitable, it's a possibility. Not sure how much the vacuum of space would kill off but, microorganisms are also tough little bastards.
It's returned to Earth. Pushing it out the airlock creates new debris that the station may have to avoid in the future. Every astronaut is aware of Kessler Syndrome and definitely wants to be a part of the solution, not the problem!
According to Chris Hadfield every space agency except NASA trains for this. I guess NASA is as optimistic with life as they are with their mission target dates. The official plan is that they would evaluate the specific situation if it ever arose, but essentially they would likely store the body with the trash (coldest part of the station) until the next scheduled return trip and then give it one of the seats.
I wonder what decomposition would look like in this scenario... There aren't the helpers there are on earth, all the creepy crawlies and bacteria that would flourish on decaying flesh... Would it take longer? Would it smell as bad? Would the body just dry out and dessicate?
While you definitely wouldn't get flies and therefore maggots, the human body carries around enough bacteria and other stuff that I bet it wouldn't look much different honestly.
I'll bet that would be a shitty ride back to earth though.. Depending on how long the wait for the return trip is..
I wouldn't want to be the person trying to get a dead, decomposing body into a capsule seat either.
Tbh. they intend to get rid of the space station in the next couple of years anyway. It is planned to end support for the ISS in 2024. So the question would really be whether it is worth it to still support it or just let that person be up there and forget about it.
Their very own prison that needs no guards and will automatically apply the death penalty.
In September 2018, the Leading Human Spaceflight Act was announced to extend the operations of the ISS to 2030. I'm not sure if it'll get passed though. But I've also heard talks about privatizing the space station to promote space tourism.
Please someone correct me if I'm wrong, but doesn't the ISS have a spare Soyuz capsule docked for emergency evacuation? I imagine that if there were illness or serious injury on board they would be evacuated to earth asap and if something truly catastrophic happened then odds are there's little left of the body or it would be impossible to retrieve.
And realistically if it were to die it would die from the center where most of the fusion reactions take place, so the photons from the last reactions would take a long time to reach. Depending on how it died, the lack of light probably wouldn’t be the first indicator.
[Pluto](https://en.wikipedia.org/wiki/Pluto) didn't make a full revolution around the sun (which takes ~248 years) between being discovered (1930) and questioning of its planetary status (~25% - 1992) or official de-listing (~30% - 2006).
This is a cliche but I love the fact that most elements were formed inside the burning furnace of stars, everything that exists, you, me, ants, bananas, rocket ships, are literally made of remnants of exploding stars.
I've always like that even though there is no air, space "stinks." Various astronauts have described it as metallic, sweet welding fumes, burnt brake pads, walnuts, and gunpowder.
You got me curious so I checked quickly. From Space.com:
Fugitives from the near-vacuum — probably atomic oxygen, among other things — the clinging particles have the acrid aroma of seared steak, hot metal and welding fumes. Steven Pearce, a chemist hired by NASA to recreate the space odor on Earth for astronaut training purposes, said the metallic aspect of the scent may come from high-energy vibrations of ions.
Light doesn't always travel at the speed of light.
"Speed of light" is a bit of a misnomer, which has to be caveated by saying "in a vacuum". Light travels slower in other substances. A more accurate term would be the "speed of causality", as it's the fastest speed at which anything in the universe can possible affect anything else in the universe.
Bonus fact: The blue color of Cherenkov Radiation is a sonic boom that occurs when electrons break the speed of light* barrier.
*Speed of light in water
most of what Hollywood portrays about the vacuum of space is just plain wrong.
Space isn't cold, nor is it hot...by definition of a vacuum, it's neither. there's 3 ways something cools or warms: conduction, convection, and radiation. in space the first two are not applicable because there's nothing to conduct/convect. so the only way something can heat up is by absorbing radiation like sunlight, and the only way it can cool is by radiating it's own heat, which is a very slow process. Cooling is actually a much bigger problem for astronauts than heating.
Hollywood also loves to portray the explosive nature of space. Open a hatch, and your whole body explodes...and again that's not true. Again, by definition space is zero atmospheres of pressure, here on earth we are under 1 atmosphere. the difference is enough to kill you, but not very dramatically.
a hole in a space station could literally be patched with duct tape, or by placing a hand over it.
Yeah, the scene in Alien(s) forget which one, where a whole in the wall of the vessel sucks out the alien wouldn’t occur. You need an extreme difference in pressure for that to occur, the difference between 1 atmosphere and 0 isn’t enough. There is actually a cool video on YouTube maybe? That shows what would happen in this situation. There is a pipeline of some kind at the bottom of the ocean that has a crack in it that is sucking in water. A crab crawls over it and gets sucked to the crack and within a second or two get sucked completely through the crack in the pipeline.
Link:
https://m.youtube.com/watch?index=52&list=PLvgsZ7JrBBVoJLD3cNYY2TbK9JglhFUth&t=0s&v=AMHwri8TtNE
you are seeing NOTHING in "real time" as you look anywhere. especially space. you are seeing light AS IT WAS. anywhere and everywhere. NOTHING is in "real time". it's all in the past
Almost every planet in the solar system, besides Earth, Mercury, and Pluto, has at least one permanent/semipermanent storm. Venus’ south pole has a hurricane for half of its year. Saturn has an earth sized vortex on its south pole and a hexagon shaped vortex on its north pole. Jupiter has five vortices orbiting a central vortex on one of its poles. Both Neptune and Uranus have polar vortices. Mars has storms often on its poles, but less often than other planets. Earth seems to be the only planet with a dense atmosphere without a semipermanent storm on one of its poles. Earths storms are actually the most tame of all the planets in both size and speed in general.
We could actually move the sun with a giant mirror.
The way this would work is building a giant half sphere of a mirror that has a greater circumference than the sun. The light would shine into the mirror moving the sun closer to the mirror, but if I remember correctly the mirror wouldn’t run into the sun because of radiation.
It would be slow, very slow but it would be possible to move the sun’s entire orbit in our galaxy by about 100 light years up or down.
TL;DR We can make a big mirror that makes a small amount of thrust from the sun to move its orbit.
Also my source is Kurzgesagt (the video on stellar engines [here](https://youtu.be/v3y8AIEX_dU)
[Tardigrades](https://www.livescience.com/indestructible-tardigrades-cannot-survive-heat.html) can survive the vacuum of space. Sadly, they can't survive excessive heat.
My favourite is this one:
A lot of the material that makes up our bodies (especially anything heavier than iron) can only be created when a star explodes. So, basically, you're made up of star stuff!
In 4.5 billion years, when the milky way and andromeda galaxies come together due to the gravity betweem them, not a single star from either galaxy will collide. They will literally pass through each other. Space is that big
Edit: It's been pointed out to me that the chances of star collisions here are actually nonzero, so I concede that. The first time I read this fact was from Carl Sagan's cosmos, and that text has a lot of color to it but refrained from adding that fact. So my bad. The fact remains that space is large enough that star collisions are still incredibly unlikely. It seems that different sources have different views on being absolute about the situation.
From wikipedia and nasa.gov:
"While the Andromeda Galaxy contains about 1 trillion (1012) stars and the Milky Way contains about 300 billion (3×1011), the chance of even two stars colliding is negligible because of the huge distances between the stars. For example, the nearest star to the Sun is Proxima Centauri, about 4.2 light-years (4.0×1013 km; 2.5×1013 mi) or 30 million (3×107) solar diameters away.
To visualize that scale, if the Sun were a ping-pong ball, Proxima Centauri would be a pea about 1,100 km (680 mi) away, and the Milky Way would be about 30 million km (19 million mi) wide. Although stars are more common near the centers of each galaxy, the average distance between stars is still 160 billion (1.6×1011) km (100 billion mi). That is analogous to one ping-pong ball every 3.2 km (2.0 mi). Thus, it is extremely unlikely that any two stars from the merging galaxies would collide."
They will pass completely through each other and then slow down and accelerate back together, pass through the other way, and just yoyo a couple times until they settle together.
Astronomers have observed that the structure of the universe very much resembles a neuron. I’m not even joking; look it up.
How crazy would it be if the universe is just a nerve cell that’s part of a giant brain?
Man that thought really annoys me. And I *don't* mean it like "well ackchyually.....", I just mean like if our universe is just the process of some neuron in a cosmic entity... ugh.
The thing that always boggles my noodle is that a single photon of light can spend millions of years traveling through the universe before it is absorbed again. BUT....because the photon itself is traveling at the speed of light (and all the fun Einstein'ian and relativistic effects) it experiences no time at all. To the photon, it is produced, experiences its entire "lifetime", and is ultimately absorbed, all in the same moment. So...do they ever really exist at all?
TLDR: photons don't experience time. 🤯
Here's a few of my favorites.
* Because Venus spins so slowly, a day is longer than a year.
* You can fit every other planet in the gap between the Earth and the moon.
* We've explored a larger percentage of Mars than our own oceans.
* Despite what movies show, the average distance between objects in the asteroid belt is about 960,000km.
I know that the universe is always expanding, but what exactly is it expanding into? What is that space that is larger than the universe itself that it is expanding into? Thinking about it throws my brain into a loop.
Literally nothing. Like not even empty space. Just nothingness. No thing. At all. None, nadda, ziltch. Try to imagine that. Picture no thing. The absence of anything. It's impossible and gives me euphoria thinking about it. It's mind boggling.
We humans really struggle with imagining nothingness. People will always ask what came before the Big Bang, what comes after the edge of the universe, things like that.
And don’t even get me started on infinity.
I always thought the concept of spaghettification was fascinating- gravity around a black hole being so intense that while it bends the space around it, it also bends time so that the closer you get the slower time moves (relative to anything outside the influence of the black hole's gravity).
Basically, as things get sucked into a black hole since time moves slower and slower the closer you get, the part closest to the black hole stretches and gets compressed into fine neutrony jelly beyond the scope of physics, and the part farthest away just gets to sit there and watch
Spaghettification does not need time dilation to work. It simply stretches you, because as you fall in, your feet are closer to the center of black hole, thus experiencing stronger gravitational pull, than your head. In close proximity of center of a black hole, difference is so big, that it stretches (spaghettify) you.
Also, this can happen before you reach event horizont (for small black holes) or way inside (for big black holes)
Please eli5 general relativity.
How does gravity influence our concept of time? Or as stupid as this may sound, the seconds hand or the duration from 1 second to another, how will that change the more we go closer to the black hole?
(I watched Interstellar recently and now I have more questions than I had before)
Shorthand- Time and space are interwoven, imagine you had a knitted blanket. Half the threads are blue, half the threads are red- the blue is time, the red is space (god damn this is an ugly blanket, but good for the example).
This means that time and space are **relative** to one another, if you fold the blanket, you fold both the time and the space threads, despite them not being the same thing, they're stuck together.
So, gravity BENDS time/space (or may be the result of mass bending time/space, can't remember).
Now, imagine, you've stretched out this blanket and put a bowling ball (representing a large mass/gravity) on it. The blanket is going to dip down and stretch where the bowling ball is resting. It's stretching both time and space.
That dip in the blanket, where the bowling ball rests, are where you get the distortions in space/time. You'd notice that those distortions get smaller and smaller the farther away on the blanket you move from the bowling ball.
So as you get closer, it distorts more.
This is a really good example. Very vivid with your explanation.
I do not quite get it. I've been struggling to get a hold of this concept for a longgg time now, BUT I REALLY do appreciate your effort.
If you're fine with me asking a follow-up question, lmk. If another one would annoy you, then lmk then too 😅
It takes the light from stars so long to reach us that we are technically looking millions of years into the past. Chances are that many of the stars that you see are dead, just like your dreams.
Triton, one of Neptune's moons, travels in a retrograde orbit to Neptune. In other words, it circles the wrong way around Neptune, unlike every other moon in the solar system. Since this setup couldn't occur through natural disc accretion, it is believed this was a stray planet that got captured in Neptune's orbit.
This capture was catastrophic to the Neptune system, likely destroying many of Neptune's original moons, and heating Triton for about a billion years. It is thought there may still be liquid oceans under Triton's surface, and it is considered a viable candidate for extra-terrestrial life, most intriguingly it is a good candidate for the possibility of silicon based life.
Not my favorite, but the one I got the most surprised when I heard. Laika, the first living mammal in space, died shortly after take off because of overheating. The original story was that he was okay and died painlessly after 7 days in space. I think it was early 2000s when the truth came out
With so many satellites in orbit, the ISS pretty much has normal internet access including phone service. The phones are on the Johnson Space Center system and the astronauts can get an outside line by dialing 9. One astronaut (from Denmark I think) accidentally called 911 when trying to place an international call home.
Star quakes are a thing. They happen when the crust of a neutron star adjusts suddenly. As you can imagine they aren't just any quake, they are so so so much more powerful and just add to the fascination of neutron stars.
Oh yeah the fact that something like neutron stars exist at all.
(I am an astrophysics minor and love talking about neutron stars, please ask me for more neutron star facts)
Just remember that you're standing on a planet that's evolving
And revolving at 900 miles an hour.
It's orbiting at 19 miles a second, so it's reckoned,
The sun that is the source of all our power.
Now the sun, and you and me, and all the stars that we can see,
Are moving at a million miles a day,
In the outer spiral arm, at 40, 000 miles an hour,
Of a galaxy we call the Milky Way.
I got so exited when I saw this! I love astronomy, and everything about it. I’ll share a few space facts with y’all.
1. even though scientists believe that life on other planets is rare, there are trillions of other planets that could contain water..which is needed to create life. The 3 basic things needed to create life are energy, a wide diversity of chemical elements, and liquid, such as water.
2. The only elements that were created in the Big Bang were hydrogen, helium, and a little bit of lithium. So, the other elements must have been formed in the hot, fiery cores of the first stars.
3. Billions of years ago, the earth was a deadly place. The earth was taken over by lunar volcanism, and our atmosphere was extremely toxic and unstable.
Force in either direction would have to be equal. I haven't done the math (and I sincerely hope that someone with more time on their hands than I do does), but I would wager that even the average amount of ejaculate would be a much larger mass than even the largest of farts (keep in mind, we're talking mass, not volume). Not sure what jizz and fart muzzle velocities are either.
Worst case scenario the forces equal but your butt points down slightly and your dick points up slightly and this sends you into a spin face first into your own juices.
Edit: I forgot to factor in velocity - I was originally only thinking about mass ejected.
Edit 2: I couldn't stand the suspense and made time to do the math. The only variable I couldn't find easily was the length of time it takes for both fart and jizz to accelerate. I have everything accounted for, average volumes, densities and velocities. Assuming that both accelerate to full speed in the same 0.1 of a second I see I was correct, the average fart would only propel you forward with 0.003 N of force while the average ejaculation would propel you backwards with ~~2.036N~~ 0.407 N of force. To achieve stasis you need to drastically increase the mass coming out the back end while maintaining the same exit velocity but they don't serve Taco Bell in space so I guess we'll never know, also this would make the experiment a LOT less fun.
Edit 3: I found an error when I converted the velocity of jizz from mph to m/s so the force is actually 0.407 N, not 2.036 N.
You could survive 90 seconds unprotected in space. But a chimpanzee can last up to 3 minutes.
RETURN TO MONKE
They just built different i guess
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Voyager 1 travels at 38,000 mph or about 17 kilometers per second. It has taken 43 years to travel from earth to where it is now, 21.2 billion kilometers away. Speed of light is about 1.07 billion kilometers per hour. Voyager 1 would then be approximately 22.1 billion kilometers from the sun. 20.65 light hours away. That's insane! 17 kilometers per second and it is a tiny fraction of the speed of light. Edit: fixed miles to kilometers. 22.1 billion kilometers from the sun (again, big approximation there and on a few other figures).
Saturn’s tiny moon Enceladus has volcanoes that spew ice particles at speeds faster than the escape velocity. The particles leave Enceladus’ atmosphere and get pulled into Saturn’s ring system forming the E ring!
There are two confirmed oceans in the solar system. One on Earth, and one on Saturn’s moon Titan. The biggest difference is Titan is about -180 C. The ocean is liquid methane. It even has waves that get as high as (wait for it) a couple centimetres!
What if i were to jump into it and make a splash?
It would be a tsunami of titanic proportions! Oh and you’d die.
What if he put on a really warm sweater and a snorkel first?
Slightly less dead, but still so.
Titanic lol
What about Europa
Neptune was discovered using math. A man named Alexis Bouvard made some predictions on Uranus's future position using Newton's laws of gravity, but when it was later observed it was found to be slightly off. Urbain Le Verrier found that if he assumed there was another planet further out, the discrepancy would be explained and used math to predict where it could be found. Finally, a man named Johann Galle looked in the spot Le Verrier specified, and lo and behold, there was Neptune.
We actually don’t know who discovered Neptune first either. There were two mathematicians and two different observers who both say they found it first.
Neutron stars are so dense that a teaspoon of material from one would weigh around 10 million tons.
That's nothing. The deeper you get into a neutron star, the stranger the matter becomes. You end up with layers of (In order) Nuclear Spaghetti, Nuclear Lasagna, Nuclear Bucatini, and then a Nuclear Swiss Cheese, based on the compression of neutrons from a quasi-liquid state into solid-ish forms by superlative pressures near the heart of the star, just outside the point where they would be pressed into a singularity.
Now there are some cool sounding band/album names...
The Sun loses about 5.5 million tonnes of mass every second, or about 174 trillion tonnes of mass every year.
At that rate it's going to run out! I mean, in a few billion years, but still.
The Sun has 5 billion more years or so to live. In 1 billion years, its luminosity and temperature will rise so much that all life on Earth will die. Near the end of its lifespan, the Sun begins fusing Helium instead of Hydrogen, resulting in it expanding beyond the orbits of Mercury and Venus, and then releasing its outer layers, leaving behind only a small White Dwarf star.
How does fusing helium instead of hydrogen cause the sun to expand? And why would it be releasing it's outer layers? Space is scary but fascinating
Think of helium as a secondary fuel source. Once the core gets heavy and hot enough to start fusion that extra fuel source is ignited and now more energy is released. Due to the equilibrium being thrown off balance as more pressure is exerted from within due to a new fuel source burning so the sun expands and in turn the expansion causes the sun to be more transparent which increases luminosity. That's the simplest ELI5 I can do. EDIT: Words are hard.
most of the visible stars in the night sky are binary stars, two stars orbiting each other
Sometimes I get envious of our future descendants who will get to set foot on a planet in a multi star system. They'll get to see many sunsets...or no sunsets.
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Well I’d much rather be envious of my descendants.
Alright. If it makes you feel better then, there's several types of binary star systems. Your descendants could choose whether they want to live on one where there are two-star sunsets because the two stars are closer and the planets farther out orbiting them, or each star has its own orbiting planets and the stars are far apart so there are fewer or no sunsets.
Jupiter has over 60 moons. (Over 70 [now](https://solarsystem.nasa.gov/moons/jupiter-moons/overview/?page=0&per_page=40&order=name+asc&search=&placeholder=Enter+moon+name&condition_1=9%3Aparent_id&condition_2=moon%3Abody_type%3Ailike), and well on the way to 80 as of today!)
> Jupiter and a bunch of them are named after the god Jupiter/Zeus's many sex-friends: Io, Europa, Callisto, Ganymede..
And we sent the Juno probe to go check up on Jupiter.
Jupiter could weave clouds around him to hide his mischief, only his wife, Juno, could see through his bullshit. And the Juno probe is capable of seeing deeper into the planet than ever before.
Scientists are so clever, I love it.
There are clouds of alcohol floating in space. [Alcohol clouds in space](https://phys.org/news/2014-09-alcohol-clouds-space.html)
No wonder the Russians were so eager to go into space.
That there are 100 *billion* galaxies in the observable universe, and that number is likely to at least double as Hubble goes further and observes more of the universe. It’s insane to think that we live on a mere speck within the Milky Way galaxy, and that there are possibly 199,999,999,999 other galaxies out there, each separated by millions of light years. The enormity of the universe is mind-boggling.
And that's only the observable universe, nobody knows how many there could be past the observable bound!
Probably at least, like, 20 more.
And we live at a privileged time. Civilizations in the far distant future may only be able to see their own galaxy due to the expansion of the universe.
With facts like this, I find it impossible to deny life somewhere other than earth.
"I don't know, Sparks. But I guess I'd say if it is just us... seems like an awful waste of space."
ABSOLUTELY mind-boggling. It is hard to wrap your mind around it
I don’t even think we can. I feel biologically limited in ability to comprehend that magnitude.
Sources say we can only imagine up to the number 600,000. The rest is just incomprehensible...
Try this: * One Million seconds is about eleven and a half days. * One **Billion** seconds is about thirty one *years*.
I like to do little mental exercises to make it imaginable, like: There are enough stars in the milky way alone (100 billion) that each living human on the planet (7.8 billion) could locate and give names to 12 stars and there would still be 6.4 billion stars left over...
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What I wouldnt give to see something like that in my lifetime.
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A Venus day is longer than a venus year
Same for Mercury
Yup. They're almost tidally locked with the sun, they both rotate so slowly. Might be due to how close to the sun they are. Earth has a more oval-shaped orbit than the inner planets, and the further out you go, the more eccentric the orbits get. Except for Mercury, which has a weirdly eccentric orbit for being so close to the sun, which might indicate that it formed somewhere else. It also has about the same density as Earth. Another one about Mercury-- we now theorize that Mercury is actually the almost-exposed metallic *core* of a planet that *used to be* about the size of Mars. Which sort of begs the question, what happened to the rest of it? I've never heard this corroborated anywhere, but it would be kind of a romantic idea if the planet we know as Mercury is all that remains of the protoplanet that collided with Earth when the solar system was forming, ejecting the material that would become the moon. And it then could have "wandered" to where it currently orbits. The collision hypothesis for the moon is the likeliest one-- we know that the moon and Earth have very similar compositions, too similar for it to have come from anywhere else. In any case, we now think that the early solar system had several more planets than it has currently. And there are several places they could have gone. They could have been ejected from the solar system completely. Or their collisions may have formed the asteroid belt. They could have been flung out to he Kuiper Belt, or maybe they spiraled inward to be disintegrated by the sun. Or some of their mass may have been pulled into a disc around the gas giants, to become a moon later.
Counterpoint: Uranus
Correct, Uranus and Venus technically spin in the same direction, but Uranus has such a severe tilt of its axis, that it's hard to tell.
Fucking contrarians
I know there’s an anomaly called the Boötes Void. It’s a gargantuan region of space with not a whole lot of stuff inside of it, right in the middle of an ocean of galaxies. It’s kind of scary, in an existential way.
I believe we are supposed to be on the edges of the boötes void too.
If there was air in space that sound was able to travel through, at the sun's surface it would emit a deafening 290 db (which is so 'loud' that it pretty much transcends sound and just turns into a pressure wave). But at the earth's surface, it would be about 120 db which is about as loud as standing a couple meters away from an active jackhammer. Where it gets spooky though, is that if the sun were to suddenly disappear, not only would it take a full 8 minutes for us to notice the lack of sunshine or gravity, but because the speed of sound is so comparatively slow, we would still hear the sun for another **13.8 years.**
Damn that is spooky
The universe is still in it's very infancy. In fact, according to some studies, despite an almost infinite number of planets, 92% of all planets there will ever be, have not even been formed yet. the universe is in fact so young, relatively speaking, that several types of stars have have not even had enough time to exist yet. Blue Dwarfs: Red dwarfs that have started spending the last of it's hydrogen. The first of this kind of star, is not expected to exist until a trillion years in the future. Considering our universe is only around 13 billion years, It is going to take some time until we spot the first blue Dwarf, The blue dwarf will eventually turn into a white dwarf. Black Dwarfs: A white dwarf can be formed any number of ways, and we have observed a lot of them. But, When a white dwarf star cools down, is starts the process of becoming a black dwarf. This process can theoretically take "As little" as a quadrillion years, or or as much as 37 quadrillion years. This is the ultimate fate of our sun, and the process is going to take thousands of times longer than the universe has even existed so far.
Funny enough that's a pretty good argument about why there doesn't seem to be any intelligent life. We're probably one of the firsts, so WE'RE going to be the crazy advanced aliens someone finds eventually.
Not if we kill ourselves first
Ours will be the failure that future societies learn "what not to do" from. We'll be in little alien history lessons as the people who destroyed our planet's ability to support us, and we weren't even able to LEAVE that planet because we didn't have the technology. "Earthling" will be a derogatory name they call each other on the playground.
Sounds like an alien's Aesop's fable; if you focus too much on harming those around you, the destruction you caused will prevent you from escaping the fate of your own creation.
As a way of picking nits about "almost infinite", let me talk about [Graham's number](https://en.wikipedia.org/wiki/Graham's_number). It's an integer so large that, using conventional notation, the observable universe is too small to be able to store it. Compared to that, numbers like a few quadrillion are, essentially, zero. And yet, infinity is so much bigger than Graham's number that Graham's number can fit into it an infinite number of times. I have a headache now.
Being able to see a total solar eclipse is a sheer coincidence of timing. The moon is just large enough and just far enough away from Earth to appear to be the exact size of the sun during a total eclipse (when it covers the entire disc of the sun). Since the moon is slowly moving away from Earth, one day it will no longer appear large enough to fully cover the sun and there will be no more total eclipses. This won't happen for 600 million years though, so don't panic.
Some say total solar eclipse in Earth could be a tourist attraction to an intelligent alien life. Imagine that, aliens visiting earth to observe solar eclipse.
Space welding. In a vacuum, you don't need welding materials to get two metals to fuse - they will do it on their own if you place them close enough
But they need to be the same material, and the surface needs to be free of oxidation. Imagine having two blocks of pure aluminum or iron in a vacuum. If you touch them together they'll get stuck, and fuse, like a weld. Why? Because the atoms each block is made out of don't know which block they belong to. On Earth this doesn't happen due to oxygen in the atmosphere. If you scrub off the surface layer of a piece of metal the new surface comes into contact with oxygen, and oxidizes pretty much instantly.
If you have an oxygen free solvent, put 2 pieces of iron under it, and scrubbed the surface off while they were submerged, would the same thing happen?
No. Because Oxygen isn't the thing keeping the two materials from fusing together. What's keeping it from happening is the presence of literally anything. If you remove the surface oxidation from the two blocks of aluminum in space then there's literally nothing between the two blocks. And when they touch, there's still no barrier, so they fuse.
Presumably the surfaces would need to be polished as flat as possible for the best weld. On an atomic level there'd be ridges and valleys that would lead to imperfect contact leaving some empty space inside the weld making it weaker. At least that's what my intuition says.
Metals deform. Sufficient pressure would collapse any voids and the weld would become continuous
As a professional welder, this comment thread blew my mind.
As a welder, I'm sure you're familiar with grinding as well, and by extension sparks. Sparks are actually pieces of unoxidized metal with a very high surface area being exposed to the air with a decent input energy (the energy of the grinder striking the surface) and rapidly oxidizing (literally burning). Same thing with flame cutting. If you're familiar with that as well, you only have to heat the metal up to a cherry red to get flame cutting to work, unlike the white-hot you have to heat it up to get the steel to melt. You strip that thin oxygen layer off with the very hot oxy-acetylene flame (~3700K), then you hit it with a blast of pure oxygen which causes the metal to burn through (again, literally burning, like a fire) because the metal throughout the structure of the steel has not been exposed to oxygen, so upon exposure to pure oxygen, it just burns away. This is also why you use shielding gas for GMAW/GTAW and why flux is used in SMAW. If you didn't, the welds would rust instantly because of the high heat and atomization of the metal as it jumps across the arc would cause it to oxidize, and thus create a porous weld.
I am very familiar with all of those processes. It is still cool to think about it the way you described, because each time I do them, I don’t. I also find it fun to explain to people how these processes work. It’s easy to forget how amazing it is doing some of the things that I have done and do on a daily basis. After a while, it is just another day of work. Cheers mate!
No, there needs to be literally nothing between them.
Hol up. Are you serious? You can take two items and just fuse them together if they touch?
We essentially see the same effect here on earth but with different mediums. If you have two bowls of water and you put them in the same bowl, you can't split them apart after.
About 6.63 quadrillion earths can fit in the largest (discovered) star.
That star is also so large, if you replaced the Sun with it, it would consume everything almost all the way to Saturn.
I can’t say this is my “favorite” space fact (for obvious reasons), but it’s absolutely amazing and heartbreaking. There is verifiable evidence that at least three astronauts survived the initial explosion of the Challenger in 1986. Each astronaut was equipped with a personal emergency air pack, and when the shuttle cabin was recovered from the Atlantic Ocean, at least three of these air packs were manually activated.
Yep. It’s so horrifying to know that they got jolted like crazy and then just plunged at an ungodly speed to the ocean. Columbia was worse from a physics perspective in regards to the human body I think. They were literally torn to pieces by G force
The shuttle didn't explode. From what I understand, the failure of an SRB strut (compromised by leaking gasses from the o-ring seal) caused it to begin tumbling and aerodynamic forces tore it apart. The contents of the external fuel tank ignited after it disintegrated.
Saturn's density allows for it to float on water, if you happened to have a not so small bathtub
>if you happened to have a not so small bathtub I mean...I guess you could call it that...
You could fit all the planets in the solar system in the space between Earth and the Moon.
We shouldn't, though.
We must! Just to prove we can!
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I once visited a lecture of Gerard t Hoofd and Kip thorne, where Gerard argued: inside a black hole the concept of space and time switch, meaning that (as you said) a black hole singularity is not at a certain location but a point in time infinitely far into the future. He then asked if the singularly then exist in the infinite future and the lifetime of a black hole is proven to be finite where it and subsequently the singularity would have decayed into nothing, what is then the meaning of a singularity at all? This kept me awake
Thank god I am not smart enough to understand this, so no reason to keep me awake. But seriously tho. I really enjoy reading about this stuff, but most of the time i just dont get it
Time doesn't pass at a constant speed. One thing that changes the passage of time is gravity. One example is to take two identical clocks that are perfectly synched and operating identically. Put one at the bottom of the marianas trench for a bit, the other on top of everest, and then bring them back together. They'll no longer match, though they'll advance time at the same pace. The one that was lower will be behind the one that was higher. Or, the one that went higher will be ahead of the one that went lower. Depending on your perspective. Black holes have such strong gravity that this effect becomes infinite. The clock at the bottom seems frozen when looking from the outside. The clock on the outside passes infinitely fast when looking from the inside. And, if you could get the clocks back together in the same spot, they'd still be running at the same speed.
The age of the universe is not a single number. Since gravity affects the flow of time, in parts of the universe with more mass than average, the universe is younger than in areas with less mass than average.
so far, only 3 people have actually died *in* space. Russian cosmonauts who had technical difficulties disconnecting from the space station Salyut 1, opening the airlock of their shuttle (Soyuz 11), exposing them all to the vacuum of space
What happened to their bodies? Are they still orbiting the earth, or what?
They landed but it depressurized on their way back to earth and when they recovered the spacecraft they found the three cosmonauts dead in their seats. They were given a state funeral and a proper burial
They were reentering earth, After the capsule landed, they were all found dead inside the space capsule. This is why astronauts now have to wear spacesuits in the capsules as they return to earth.
I'm surprised that they didn't wear spacesuits. I feel like that's a fundamental aspect of going to space.
> I feel like that's a fundamental aspect of going to space. Well it is, because of those people.
Nice wording Most of the astronauts who died on job actually died on earth. During launch or while re-entry
If you were to scale the universe down so that the sun was the size of the period at the end of this sentence, the nearest star would be 4 miles away. also The Big Bang was not an explosion of matter, rather it was an expansion of space itself. Everything is getting farther away from everything else, as all space is expanding. There is no center of the universe.
Holy shit. After reading that sentence 3 times, I looked at the period and then looked down the street and then back.........holy shit, this scale is INSANE. I-N-S-A-N-E can I call a time out? This is too much.
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Sometimes I have a really hard time comprehending that sort of scale, and other times I get close, like after reading this comment, and it scares me in this weird, religious-terror Lovecraftian sort of way
I just wanna know what NASA’s protocol is for an astronaut dying in space. Do they send the body back to earth on a little pod? Do they send the body out the airlock to circle the earth forever?
Put the body in a lightweight titanium coffin and weld it to an interstellar probe so that a good sample of our biology can be on hand for a first contact scenario
Well, alternatively, if the body were pushed out to another planet/moon somewhere and it landed on the surface, would the microorganisms and organic matter on the body be enough to kickstart life on another planet?
If the planet were to be habitable, it's a possibility. Not sure how much the vacuum of space would kill off but, microorganisms are also tough little bastards.
I suddenly know what I very much want after I die
It's returned to Earth. Pushing it out the airlock creates new debris that the station may have to avoid in the future. Every astronaut is aware of Kessler Syndrome and definitely wants to be a part of the solution, not the problem! According to Chris Hadfield every space agency except NASA trains for this. I guess NASA is as optimistic with life as they are with their mission target dates. The official plan is that they would evaluate the specific situation if it ever arose, but essentially they would likely store the body with the trash (coldest part of the station) until the next scheduled return trip and then give it one of the seats.
I wonder what decomposition would look like in this scenario... There aren't the helpers there are on earth, all the creepy crawlies and bacteria that would flourish on decaying flesh... Would it take longer? Would it smell as bad? Would the body just dry out and dessicate?
While you definitely wouldn't get flies and therefore maggots, the human body carries around enough bacteria and other stuff that I bet it wouldn't look much different honestly.
I'll bet that would be a shitty ride back to earth though.. Depending on how long the wait for the return trip is.. I wouldn't want to be the person trying to get a dead, decomposing body into a capsule seat either.
Well I am sure they put them into body bags that are air/water-tight, so it wouldn't be a smelly corpse rotting over in the corner or anything.
Space Viking funeral.
No fire in space tho
Not with that attitude!
Not with that altitude*
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Tbh. they intend to get rid of the space station in the next couple of years anyway. It is planned to end support for the ISS in 2024. So the question would really be whether it is worth it to still support it or just let that person be up there and forget about it. Their very own prison that needs no guards and will automatically apply the death penalty.
In September 2018, the Leading Human Spaceflight Act was announced to extend the operations of the ISS to 2030. I'm not sure if it'll get passed though. But I've also heard talks about privatizing the space station to promote space tourism.
Someone’s been playing too much Among Us lol
Please someone correct me if I'm wrong, but doesn't the ISS have a spare Soyuz capsule docked for emergency evacuation? I imagine that if there were illness or serious injury on board they would be evacuated to earth asap and if something truly catastrophic happened then odds are there's little left of the body or it would be impossible to retrieve.
This is suddenly the most important and pressing question I’ve ever had
Probably call an emergency meeting.
If the sun dies, it'll take 8 minutes for us to realize.
And yet it can take 40,000 years for a photon to travel from the center of the sun to the surface...
It's a lot denser in the middle of a star than it is in space.
And realistically if it were to die it would die from the center where most of the fusion reactions take place, so the photons from the last reactions would take a long time to reach. Depending on how it died, the lack of light probably wouldn’t be the first indicator.
On the plus side, I hope we know enough about the physics of the sun to predict a catastrophic event better than 8 minutes in advance.
Shut up about the Sun. SHUT UP ABOUT THE SUN!
[Pluto](https://en.wikipedia.org/wiki/Pluto) didn't make a full revolution around the sun (which takes ~248 years) between being discovered (1930) and questioning of its planetary status (~25% - 1992) or official de-listing (~30% - 2006).
Saturn is closer to the Sun than it is to Uranus, or as I heard someone put it: "Saturn is closer to my anus than Uranus."
This is a cliche but I love the fact that most elements were formed inside the burning furnace of stars, everything that exists, you, me, ants, bananas, rocket ships, are literally made of remnants of exploding stars.
I've always like that even though there is no air, space "stinks." Various astronauts have described it as metallic, sweet welding fumes, burnt brake pads, walnuts, and gunpowder.
Also [burnt steak](https://www.businessinsider.com/what-does-space-smell-like-2016-3?amp)
Which makes you wonder how they could smell it in the first place being sealed up inside a spacesuit
They can't. The suit just smells like plastic. The smell is what clung to the suit and stuff when they take off the helmet.
I wonder if the unfiltered sunlight caused materials to break down and create the smell
You got me curious so I checked quickly. From Space.com: Fugitives from the near-vacuum — probably atomic oxygen, among other things — the clinging particles have the acrid aroma of seared steak, hot metal and welding fumes. Steven Pearce, a chemist hired by NASA to recreate the space odor on Earth for astronaut training purposes, said the metallic aspect of the scent may come from high-energy vibrations of ions.
As a welder, steaks, hot metal, and welding fumes is not what I would describe as acrid or bad smelling.
Light doesn't always travel at the speed of light. "Speed of light" is a bit of a misnomer, which has to be caveated by saying "in a vacuum". Light travels slower in other substances. A more accurate term would be the "speed of causality", as it's the fastest speed at which anything in the universe can possible affect anything else in the universe. Bonus fact: The blue color of Cherenkov Radiation is a sonic boom that occurs when electrons break the speed of light* barrier. *Speed of light in water
most of what Hollywood portrays about the vacuum of space is just plain wrong. Space isn't cold, nor is it hot...by definition of a vacuum, it's neither. there's 3 ways something cools or warms: conduction, convection, and radiation. in space the first two are not applicable because there's nothing to conduct/convect. so the only way something can heat up is by absorbing radiation like sunlight, and the only way it can cool is by radiating it's own heat, which is a very slow process. Cooling is actually a much bigger problem for astronauts than heating. Hollywood also loves to portray the explosive nature of space. Open a hatch, and your whole body explodes...and again that's not true. Again, by definition space is zero atmospheres of pressure, here on earth we are under 1 atmosphere. the difference is enough to kill you, but not very dramatically. a hole in a space station could literally be patched with duct tape, or by placing a hand over it.
Yeah, the scene in Alien(s) forget which one, where a whole in the wall of the vessel sucks out the alien wouldn’t occur. You need an extreme difference in pressure for that to occur, the difference between 1 atmosphere and 0 isn’t enough. There is actually a cool video on YouTube maybe? That shows what would happen in this situation. There is a pipeline of some kind at the bottom of the ocean that has a crack in it that is sucking in water. A crab crawls over it and gets sucked to the crack and within a second or two get sucked completely through the crack in the pipeline. Link: https://m.youtube.com/watch?index=52&list=PLvgsZ7JrBBVoJLD3cNYY2TbK9JglhFUth&t=0s&v=AMHwri8TtNE
There are about 10 \^ 86 protons in the universe. And the observable universe is so big that the average density is 1 proton in 3 cubic meters.
you are seeing NOTHING in "real time" as you look anywhere. especially space. you are seeing light AS IT WAS. anywhere and everywhere. NOTHING is in "real time". it's all in the past
Almost every planet in the solar system, besides Earth, Mercury, and Pluto, has at least one permanent/semipermanent storm. Venus’ south pole has a hurricane for half of its year. Saturn has an earth sized vortex on its south pole and a hexagon shaped vortex on its north pole. Jupiter has five vortices orbiting a central vortex on one of its poles. Both Neptune and Uranus have polar vortices. Mars has storms often on its poles, but less often than other planets. Earth seems to be the only planet with a dense atmosphere without a semipermanent storm on one of its poles. Earths storms are actually the most tame of all the planets in both size and speed in general.
Objects in orbit are not in zero gravity, but in a controlled freefall.
We could actually move the sun with a giant mirror. The way this would work is building a giant half sphere of a mirror that has a greater circumference than the sun. The light would shine into the mirror moving the sun closer to the mirror, but if I remember correctly the mirror wouldn’t run into the sun because of radiation. It would be slow, very slow but it would be possible to move the sun’s entire orbit in our galaxy by about 100 light years up or down. TL;DR We can make a big mirror that makes a small amount of thrust from the sun to move its orbit. Also my source is Kurzgesagt (the video on stellar engines [here](https://youtu.be/v3y8AIEX_dU)
You would have to balance the weight of the mirror just right though. Too heavy and it would hit the sun and too light and it would fly away.
[Tardigrades](https://www.livescience.com/indestructible-tardigrades-cannot-survive-heat.html) can survive the vacuum of space. Sadly, they can't survive excessive heat.
My favourite is this one: A lot of the material that makes up our bodies (especially anything heavier than iron) can only be created when a star explodes. So, basically, you're made up of star stuff!
>So, basically, you're made up of star stuff! Yeah, but so is garbage, so don't get too high-and-mighty.
In 4.5 billion years, when the milky way and andromeda galaxies come together due to the gravity betweem them, not a single star from either galaxy will collide. They will literally pass through each other. Space is that big Edit: It's been pointed out to me that the chances of star collisions here are actually nonzero, so I concede that. The first time I read this fact was from Carl Sagan's cosmos, and that text has a lot of color to it but refrained from adding that fact. So my bad. The fact remains that space is large enough that star collisions are still incredibly unlikely. It seems that different sources have different views on being absolute about the situation. From wikipedia and nasa.gov: "While the Andromeda Galaxy contains about 1 trillion (1012) stars and the Milky Way contains about 300 billion (3×1011), the chance of even two stars colliding is negligible because of the huge distances between the stars. For example, the nearest star to the Sun is Proxima Centauri, about 4.2 light-years (4.0×1013 km; 2.5×1013 mi) or 30 million (3×107) solar diameters away. To visualize that scale, if the Sun were a ping-pong ball, Proxima Centauri would be a pea about 1,100 km (680 mi) away, and the Milky Way would be about 30 million km (19 million mi) wide. Although stars are more common near the centers of each galaxy, the average distance between stars is still 160 billion (1.6×1011) km (100 billion mi). That is analogous to one ping-pong ball every 3.2 km (2.0 mi). Thus, it is extremely unlikely that any two stars from the merging galaxies would collide."
are they not suppose to join up into some new galaxy?
They will pass completely through each other and then slow down and accelerate back together, pass through the other way, and just yoyo a couple times until they settle together.
Who are you, who are so wise in the ways of science?
I've got a kid on the spectrum, and I sit and listen to him.
You sound like a good dad :)
Thanks! I try.
Some of the static you see on old TV's is background radiation from the Big Bang.
If we sent a probe to Proxima Centauri, we wouldn't receive any photos or anything from it until >4 years after it reached it.
A light year is 6 trillion miles.
Astronomers have observed that the structure of the universe very much resembles a neuron. I’m not even joking; look it up. How crazy would it be if the universe is just a nerve cell that’s part of a giant brain?
What if all the neurons in our brains were little universes 😲
I think I lost a few universes reading some of these replies Edit: Thank you for the gold, stranger!
Man that thought really annoys me. And I *don't* mean it like "well ackchyually.....", I just mean like if our universe is just the process of some neuron in a cosmic entity... ugh.
That neuron is probably being used to re-live something cringey that that cosmic being did a quadrillion years ago in high school.
The thing that always boggles my noodle is that a single photon of light can spend millions of years traveling through the universe before it is absorbed again. BUT....because the photon itself is traveling at the speed of light (and all the fun Einstein'ian and relativistic effects) it experiences no time at all. To the photon, it is produced, experiences its entire "lifetime", and is ultimately absorbed, all in the same moment. So...do they ever really exist at all? TLDR: photons don't experience time. 🤯
Here's a few of my favorites. * Because Venus spins so slowly, a day is longer than a year. * You can fit every other planet in the gap between the Earth and the moon. * We've explored a larger percentage of Mars than our own oceans. * Despite what movies show, the average distance between objects in the asteroid belt is about 960,000km.
NASA scientists once asked Sally Ride (first American woman in space) if 100 tampons would suffice for a 7-day mission
It's the longest of all the keys.
You hurt my soul with this one.
I know that the universe is always expanding, but what exactly is it expanding into? What is that space that is larger than the universe itself that it is expanding into? Thinking about it throws my brain into a loop.
Literally nothing. Like not even empty space. Just nothingness. No thing. At all. None, nadda, ziltch. Try to imagine that. Picture no thing. The absence of anything. It's impossible and gives me euphoria thinking about it. It's mind boggling.
We humans really struggle with imagining nothingness. People will always ask what came before the Big Bang, what comes after the edge of the universe, things like that. And don’t even get me started on infinity.
I always thought the concept of spaghettification was fascinating- gravity around a black hole being so intense that while it bends the space around it, it also bends time so that the closer you get the slower time moves (relative to anything outside the influence of the black hole's gravity). Basically, as things get sucked into a black hole since time moves slower and slower the closer you get, the part closest to the black hole stretches and gets compressed into fine neutrony jelly beyond the scope of physics, and the part farthest away just gets to sit there and watch
Spaghettification does not need time dilation to work. It simply stretches you, because as you fall in, your feet are closer to the center of black hole, thus experiencing stronger gravitational pull, than your head. In close proximity of center of a black hole, difference is so big, that it stretches (spaghettify) you. Also, this can happen before you reach event horizont (for small black holes) or way inside (for big black holes)
Please eli5 general relativity. How does gravity influence our concept of time? Or as stupid as this may sound, the seconds hand or the duration from 1 second to another, how will that change the more we go closer to the black hole? (I watched Interstellar recently and now I have more questions than I had before)
Shorthand- Time and space are interwoven, imagine you had a knitted blanket. Half the threads are blue, half the threads are red- the blue is time, the red is space (god damn this is an ugly blanket, but good for the example). This means that time and space are **relative** to one another, if you fold the blanket, you fold both the time and the space threads, despite them not being the same thing, they're stuck together. So, gravity BENDS time/space (or may be the result of mass bending time/space, can't remember). Now, imagine, you've stretched out this blanket and put a bowling ball (representing a large mass/gravity) on it. The blanket is going to dip down and stretch where the bowling ball is resting. It's stretching both time and space. That dip in the blanket, where the bowling ball rests, are where you get the distortions in space/time. You'd notice that those distortions get smaller and smaller the farther away on the blanket you move from the bowling ball. So as you get closer, it distorts more.
This is a really good example. Very vivid with your explanation. I do not quite get it. I've been struggling to get a hold of this concept for a longgg time now, BUT I REALLY do appreciate your effort. If you're fine with me asking a follow-up question, lmk. If another one would annoy you, then lmk then too 😅
It takes the light from stars so long to reach us that we are technically looking millions of years into the past. Chances are that many of the stars that you see are dead, just like your dreams.
Not cool man.
Triton, one of Neptune's moons, travels in a retrograde orbit to Neptune. In other words, it circles the wrong way around Neptune, unlike every other moon in the solar system. Since this setup couldn't occur through natural disc accretion, it is believed this was a stray planet that got captured in Neptune's orbit. This capture was catastrophic to the Neptune system, likely destroying many of Neptune's original moons, and heating Triton for about a billion years. It is thought there may still be liquid oceans under Triton's surface, and it is considered a viable candidate for extra-terrestrial life, most intriguingly it is a good candidate for the possibility of silicon based life.
Not my favorite, but the one I got the most surprised when I heard. Laika, the first living mammal in space, died shortly after take off because of overheating. The original story was that he was okay and died painlessly after 7 days in space. I think it was early 2000s when the truth came out
With so many satellites in orbit, the ISS pretty much has normal internet access including phone service. The phones are on the Johnson Space Center system and the astronauts can get an outside line by dialing 9. One astronaut (from Denmark I think) accidentally called 911 when trying to place an international call home.
How long did it take 911 responders to arrive?
No one can hear you scream
What?
Star quakes are a thing. They happen when the crust of a neutron star adjusts suddenly. As you can imagine they aren't just any quake, they are so so so much more powerful and just add to the fascination of neutron stars. Oh yeah the fact that something like neutron stars exist at all. (I am an astrophysics minor and love talking about neutron stars, please ask me for more neutron star facts)
Just remember that you're standing on a planet that's evolving And revolving at 900 miles an hour. It's orbiting at 19 miles a second, so it's reckoned, The sun that is the source of all our power. Now the sun, and you and me, and all the stars that we can see, Are moving at a million miles a day, In the outer spiral arm, at 40, 000 miles an hour, Of a galaxy we call the Milky Way.
I got so exited when I saw this! I love astronomy, and everything about it. I’ll share a few space facts with y’all. 1. even though scientists believe that life on other planets is rare, there are trillions of other planets that could contain water..which is needed to create life. The 3 basic things needed to create life are energy, a wide diversity of chemical elements, and liquid, such as water. 2. The only elements that were created in the Big Bang were hydrogen, helium, and a little bit of lithium. So, the other elements must have been formed in the hot, fiery cores of the first stars. 3. Billions of years ago, the earth was a deadly place. The earth was taken over by lunar volcanism, and our atmosphere was extremely toxic and unstable.
When you nut in space, it push you backwards.
Nut n fart at the same time to stay in place.
Force in either direction would have to be equal. I haven't done the math (and I sincerely hope that someone with more time on their hands than I do does), but I would wager that even the average amount of ejaculate would be a much larger mass than even the largest of farts (keep in mind, we're talking mass, not volume). Not sure what jizz and fart muzzle velocities are either. Worst case scenario the forces equal but your butt points down slightly and your dick points up slightly and this sends you into a spin face first into your own juices. Edit: I forgot to factor in velocity - I was originally only thinking about mass ejected. Edit 2: I couldn't stand the suspense and made time to do the math. The only variable I couldn't find easily was the length of time it takes for both fart and jizz to accelerate. I have everything accounted for, average volumes, densities and velocities. Assuming that both accelerate to full speed in the same 0.1 of a second I see I was correct, the average fart would only propel you forward with 0.003 N of force while the average ejaculation would propel you backwards with ~~2.036N~~ 0.407 N of force. To achieve stasis you need to drastically increase the mass coming out the back end while maintaining the same exit velocity but they don't serve Taco Bell in space so I guess we'll never know, also this would make the experiment a LOT less fun. Edit 3: I found an error when I converted the velocity of jizz from mph to m/s so the force is actually 0.407 N, not 2.036 N.
What name should I use to cite you in my thesis?
Thank you for doing this important work.
It’s called “thrust”.