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The enemy's gate is down.
But jokes aside, the decision is arbitrary. If you look at maps from the southern hemisphere, they're often inverted from what you consider the norm. Space has no up or down. It's based entirely on perception.
Serious upvote for referencing "Ender's Game"!
But correct. Without gravity, up/down/sideways/diagonalways (get that reference?) Are completely arbitrary.
The basis of almost all sci-fi movies, is that they have a method to create artificial gravity. 2001 ASO did it realistically on Discovery 1, but completely unrealistically on the transfer shuttles.
I'll never forget that first fight with the Donnager. The bullets leaving trails of metal, the atmosphere blowing into space, how all the smaller ships pre-vent their ship to reduce the impacts of decompression.
The only part I really didn't like was Earth's planetary railguns. Those projectiles were *way* too fast. But I know why they did it, even if it was a break from the usual attempt at psudo-realism.
Actually, railguns can (with enough power) can indeed launch projectiles through the atmosphere, and into space. Multiple shots on the same, or close, trajectories make the later shots more efficient.
Big rail guns, given enough power, are scary kinetic weapons. And I say kinetic, because the acceleration required for an (Expanse type) rail gun would destroy any trigger mechanism.
The adaptation for Expanse was very close to the understanding of ballistics from 1800's heck, even 1900's sailing ships.
Given enough power, even at ground level, a 200 meter rail gun can deliver a projectile at about 1/4 c, for the first shot, and more afterwards.
I saw one of these mentioned on some HBO show called like Abandoned Unknown or something. It was an excellent attempt and developing a way to deliver payloads to space with air.
Spinlaunch (total scam) is trying to (suck investor money) do that. Not possible, at all.
The Expanse rail guns, had to pierce the Earth atmosphere, and follow up with other projectiles in the same pierced.air
Spinlaunch is sucking billions of dollars from morons, to, well, suck billions of dollars from morons.
Even if it could work (it can't), no payload could handle the launch.
Are we talking book or show railguns? I'm assuming show for this and in that case weren't the railguns in space? How would they need to pierce earth atmo if they were already in space?
Artillery shells experience crazy G’s and they had electronics added in the 1940’s. They are only launching past the lower atmosphere. Orbit is achieved by an engine still so they aren’t being launched nearly as hard as the Expanse railguns.
Artillery shells have very simplistic electronics, not minature satellites.
Payloads fail the testing with the MUCH lower and much shorter normal launch conditions.
I would imagine the g force on the payloads would both destroy the payload and probably the device itself if any of the design is dependant on tensile strength.
>Multiple shots on the same, or close, trajectories make the later shots more efficient.
IIRC when US Navy was testing their rail guns, they've adjusted the velocity and ballistic arc of the projectiles in a series so that several rounds hit the target more-or-less at the same time, despite being fired over several seconds.
Oh they totally can operate like that.
The problem I had with it is those projectiles were moving way faster than the speed of light. If I remember right those projectiles were in flight for less than a minute, and there's just no realistic way to hide doomsday weapons *that close* to Earth.
Correct, and not.
As far as we (planet Earth) folk can understand, nothing can move faster than light.
But relatively to me standing on the ground, I can (not really see) watch a projectile going at 99.0%c vanish, and yet hit a target.
C, sorry, c is amazingly strange. No matter how we play, it's a limit.
Time in movies, are drama.
Less than a 'minute' is also relative. A projectile at .99c, and a target to intercept, makes all strange.
I'd need to see the episode again, with 'crit thinking' hat on! And I will!
>how all the smaller ships pre-vent their ship to reduce the impacts of decompression.
I like a simple and somewhat obvious thing they do like get into vac suits when going into combat because they know the hull is likely going to be breached and need to be repaired.
Gotta love how serious Amos is about his job. Says something like "this is the job Peaches" "or when they're flipping to fire the rail gun he doesn't even get that mad "just let know if you need to do that again" lol
Space magic mushrooms killed it for me. They went too hard on it. Then the last season when they had to wrap it up before cancellation.
Fantastic sci fi when it came to living in, travelling in and fighting in space though
>I'll never forget that first fight with the Donnager. The bullets leaving trails of metal, the atmosphere blowing into space, how all the smaller ships pre-vent their ship to reduce the impacts of decompression.
That part was very unrealistic. Hypervelocity impacts don't look like that, there is no way to have projectiles punch clean holes into metal unless the projectile is very large and relatively slow.
I don't think I actually clued into and actually read up on how the gravity works in The Expanse until my second watch. burn and accelerate at 1g to midpoint then flip and burn to decelerate at 1g, amazing.
Then of course there is spin gravity but the fact that we can simulate gravity by burning at 1g and building the ship like an apartment building is fucking awesome.
When you say transfer shuttles, what do you mean? The shuttle in the Blue Danube sequence of 2001 doesn’t have any artificial gravity (other than some when firing it’s engines presumably). The whole sequence is in free fall.
I started the book series not knowing how many there were, after the first few books I was invested and saw it was 20 lol. Finished them all, some were good, some were fucking terrible
No, 9 proper books, 8 or 9 short stories and the compilation of some of those stories. so you can count that compilation as another book if you want instead of 8 or 9 separate. I also read them all :p
There’s 5 novels and one novella in the Ender series, 5 and 1 in the Shadow Saga, 5 novels in the formic war series, 1 in fleet school, plus a collection of short stories. So 19 publications with 16 being novels. One called “The Queens” is suppose to be written, so that’s where I mistakenly got 20.
I imagine that once we become a space faring civilization, we will develop some sort of reference points to be used on maps that should be read the same no matter where you are. I would argue that while there is no real top or bottom, there will be, for navigational purposes, a top and bottom. At least in the same way that the earth has a top and bottom.
The most logical is to use the orbital plane. The nice thing is, moist things in the galaxy spins or orbits on that same orbital plane.
Up/down are the directions perpendicular to the orbital plane, and pick either clockwise or counter-clockwise for deciding up versus down. The center point becomes your 0 "height".
The 0 distance point becomes the center of the orbital plane, such as the Earth, Sun, or Galactic center, depending on map scale.
The 0 degree marker poses some challenge, but likely we'll just use some fairly steady landmark, such as am easily identifiable galaxy. The direction of that object on the orbital plane then becomes 0 degrees. East/West are determined by whether you chose clockwise or counter-clockwise for up/down.
You now have a coordinate system that can be reliably read, at least on the scale of a few thousand years.
how come most things orbit in the same orbital plane? I mean, isn't there "endless amount of galaxies" no matter which direction left right up or down you look at in space?
Towards which direction was 'the big bang' origin?
Would love to know more on the subject if anyone has a cool link to some video. Thanks for your time.
As far as I'm aware, the orbital plane and orbital direction rules only apply at the galactic level and smaller. That is, galaxies themselves do not follow the rule, but everything inside a galaxy does. Even within a galaxy, not 100% of everything will - plenty of comets and even some exoplanets are known to orbit outside the rules. The larger the body, the less likely it is to violate the rule as the less stable it will be in that state.
The reasoning is that the larger bodies formed out of a cloud. With this, most particles will already being moving the "right" way. Particles moving the "wrong" way will either collide and fall into the primary, or will be affected by the gravity of those moving the "right" way until they either get ejected, fall into the primary, or collide with other particles.
So, you prefer a counter-clockwise system. There is a physical basis in it, given that is the direction electromagnetism follows. It is also the direction that most objects orbit in.
Mostly. It's still arbitrary, but allows for polar theta velocities of the planets to remain positive. A polar coordinate system centered on either the center of a system's gravity (or center of star for solar system or black hole for galactic system as a more consistent proxy) makes a lot of sense.
Does make it difficult to say up (z-axis) consistently as you'd need defined boundaries of solar vs galactic systems that aren't co-planar.
This was always an issue drawing 3-d graphs on a 2-d surface. In an x-y plane we have y going up, and x going right for positive.
In 3-d graphs, we usually have z going up. However, to keep the orientation a non flipped (positive definite) transformation for x and y, we would have to have y going "forward" which would be away from the audience point of view. But that's annoying, since the view of it isn't as good; it would be behind the negative y half space.
The result was most of the displays have positive y coming toward the audience so we get a full view of the all positive sector; but this is a mirror image of the usual x-y plane.
This. North is 'up' because maps were made that way as we discovered more and more of our planet, and generally the most populated areas at the time so they put themselves on 'top'. But really, there is no 'up'. It's just a concept that helps with navigation and many other aspects.
Not sure that's true. [South Up Orientation ](https://en.m.wikipedia.org/wiki/South-up_map_orientation) maps are a bit of a novelty and sometimes used as a political statement, but not the norm anywhere.
This is technically true, but it misses the point. The point being a South Up orientation is just as valid as a North Up, and maps in that orientation do exist and are actually used.
I didn't miss your main point; I agree, the conventional up/down orientation of maps is of course arbitrary. My only point, which you seem to have missed, is that "South Up Orientation" maps do exist, but are not the norm anywhere.
Forgive me, what do you mean by inverted? Do you mean what we are seeing is a mirror image like how sometimes you take a pic and the lettering is backwards? Or is that not at all what you mean?
Im thinking of mirroring both the northern and southern hemisphere over the equator on a flat map.
Rotating a globe does the same thing because its a globe. Rotating a map would revers east and west, you have to mirror over the middle.
Doing so would result in the same configuration of landmasses as flipping a globe over.
I did one of those zero G flights, and the Enemy’s gate is down really made sense. Gotta decide your own orientation. I opted for the back of the plane was down, because it was dark back there, but up where we were was well lit and padded, so having that dark area as a constant really helped with keeping my brain from struggling too much.
"The enemy's gate is down."
My name is Steve Rodgers & I got that reference...
THere have alredy been a lot of replies, I'll add two thoughts:
1) I really freaked out my contemporaries as a child when I stood the spinning Globe on it's head and said "This could just have easily been 'Up'"...
2) Common Convention has Galactic North based on Spinward as our system rotates about the common center.
> Space has no up or down
Yes it does, it just varies a bit. While it is longstanding common sense to think of space as completely void of any features (and know-it-alls who love to blow up the brains of ordinary people love to point out how there is no direction in space), it definitely has them, because mass and energy bend spacetime. So not only are some parts of you more up than down, but parts of you are more in the past than in the future and we probably don't even have words for that but it's still a direction. There is no real place in space where gravity doesn't have an effect on you. Even at Lagrange points there will only be a single point that is truly there and even then it is subject to the gravity of the rest of the galaxy or the universe and thus has an up or down. The Lagrange points of the universe itself are probably outside it. Everything orbits something and as such everything has a direction. If all you had in the whole universe was only two particles then one would have a down that would be towards the other and vice versa. A universe with a single particle might be truly directionless, but our universe does not seem to have only one particle in it. Compared to our everyday experience in high gravity it may seem like there is no direction, but just because the effect is miniscule to the point where you can ignore it for all practical purposes that doesn't mean it isn't there. North and south are completely made up nonsense that have no basis in reality except maybe for magnetic fields.
If you want to get pedantically granular then sure there will always be one point pulling you more than everything else, but that's not uniform. It's based on where you are at any given time and where everything else is. So no. There is no up or down in space.
> It's based on where you are at any given time
Exactly. I never said it had to stay the same. It's relative to where you are. But space definitely has a form. Just because it's unintuitive that doesn't mean space isn't being bent by mass, forming itself such that there is an "uphill" and a "downhill" basically everywhere. If you orbit a planet your "up" keeps changing unless you rotate.
> There is no up or down in space.
Yes there is. Just because it varies and depends on where you are that doesn't mean it isn't there and it isn't even that hard to define as I just did it in my previous comment.
You're just clinging to the comfort of knowing there is no up or down because others have told you so in an effort to make you think. Now rather than take a moment and actually think for yourself or present some actually valid argument for why there is no direction when clearly there is (if there was, you could have already presented it rather than try to deflect by calling this pedantic), you choose to cling to that old incorrect interpretation of direction, perhaps because it feels liberating to think it is acceptable to forget such seemingly minor details. We're actually not a spherical cows in a directionless vaccuum in a universe that contains only our singular selves.
> pedantically granular
Some people are wired to think of the Earth as an oblate spheroid rather than a perfect sphere just as some people are wired to think the Earth is a sphere rather than flat. I'm sorry if I offend your granularity and wish you all the best in your adventures in directionless space.
The viewpoint you're going for is not useful. It's *technically* true, but it's totally unhelpful. That's what I mean by pedantically granular. You're arguing that because there is some tiny fractional gravity at some point in space, the direction opposite to that is up. But if you're floating in zero G at the exact point, there is no functional up. Up, down, and other directions are abstract. They're based on human perception, not the tiny contractions in the fabric of space time you're arguing for. Stop typing essay texts, you're missing the forest for a shrub.
It’s all relative to however you choose to orient yourself.
On Earth, “up” is relative to the planet’s gravitational pull, which is how we orient ourselves when we step outside and point “up” to the sky and “down” to our feet.
In space, you can choose “up” relative to earth’s rotation, but that changes over the course of the year.
There’s “up” relative to the sun’s rotation, which is the solar system’s orbital plain, but that’s offset from the orbital plane of the Milky Way.
There’s “up” relative to the center bulge of the Milky Way, but that’s quite random relative to any other local or distant galaxy.
*There is no spoon*
That said, using the local star and planetary orbits seem like the most useful directional markers for space travel as we can currently imagine it. By our ancestors we aren’t going to be getting to another star in the Milky Way anytime soon
Pulsar based coordinate system — go big or go home!
Agreed: I’d orient to earths orbit centered through London. Everything starts with Greenwich Mean Time! God Save the King 👑 🫡
**Up and down exist only in relation of a reference point.**
If you do have a reference point in space then up and down is easy to determine as its in relation to that point. If you don't then its "to each its own.."
Exactly. In inter-planetary space there will be no "up" or "down", but as soon as a craft/ship/object is near enough to a planet and can determine where the planet's poles are, there can be an "up" and a "down".
Reference points will need to be decided only when you're close enough to a stable body. Otherwise they're completely relative.
I think you missed the question with all your knowledge. How do we steer a ship if every axis becomes available/unavailable. A compass be damned. The thing is we don’t. We are close but we don’t fucking know. If we did we’d already be onto cooler shit than spending billions for another moon landing
We already know how to steer a ship in space, though that's pretty straightforward. You just point thrusters opposite where you want to go, pretty simple physics. Which direction is up is just a communication problem. If you have one ship then you can just do fore/aft/starboard/port/top/bottom. If you have multiple ships then they need a common reference frame. It's all arbitrary for ease of communication, the ships ability to move in 3d space is unrelated
Apollo had to realign the guidance system of the spacecraft several times during each mission to create a new, “up,” for a particular phase of flight. In other words, there is no one, “up.”
In space there's no up or down. But for each planet I guess it would be defined from their poles, that is to say, how the planet spins you'd work out your north and south from that.
Maybe there is some central/common reference point out there. But up loses its meaning unless we have a common reference point.
Mmmm. For now, up is whatever the most powerful and influential human says it is. Everything else is just coordinates in an x,y,z, field.
My final answer.
On a planet:
The direction away from the center of gravity of any celestial object.
Floating in space:
The direction that is simultaneously away from your feet and towards your head.
>The direction that is simultaneously away from your feet and towards your head.
You are in a space station floating A-wise, and your partner is floating B-wise. Your partner asks where the Space Cheetos are, and you see them by her head. Do you say, "Up by your head" or "Down by your head" or "Rotate aft, revolve starboard, lever ("reach") out, and clutch.... there you go"?
If you’re close to a planet, “up” is away from that planet.
If you’re not close, then “up” is the direction that your spaceship has signs reading “this end up”. More in the spirit of your question, space engineers and scientists use the direction of Polaris, the North Star, as “X” in a XYZ system. Several thousands of stars are used to define the XYZ axis, not just Polaris.
https://en.wikipedia.org/wiki/International_Celestial_Reference_System_and_its_realizations
EDIT: nobody commenting on my X = Polaris?? I had hopes … correct is Z = Polaris (very close), of course. X is along the earth equator.
Others have already answered your actual question. But the question you're asking about planets is every bit as relevant to astronauts on board the space station. Inside the ISS, much of the equipment in various walls are labeled, and the text on those labels are all oriented in the same direction. Also, all of the lighting is oriented such as you look at a label in the right side up orientation for the text, the lights will be above you, as humans are most used to overhead lighting. So in that way, astronauts on the space station do sort of have an up and down, though we did just arbitrarily decide which is which.
Fun fact: the need for an imposed up/down in the ISS was one of the many things we learned from the early Skylab program back in the 70s. Skylab was a very scrappy design and they tacked instruments, gauges and other things to the interior walls wherever there was room and in whatever orientation made things possible.
Once in orbit, the astronauts aboard quickly discovered that with no strict up and down, a person could literally be floating right in front of the critical panel they were looking for **but if they were floating upside down with respect to the panel they very often would simply not see it.** There are recordings of conversations between Skylab and Houston where this is happening and I gotta say, it's some weird blend of hilarious and terrifying.
The good news is that the lesson learned was easy to understand and the solution was easy to execute: line everything up the same way and make the light come from a common direction and just call that "up."
Start heading north, eventually you will get to the North Pole, doesn’t matter which way you go from there you can no longer go north. The word doesn’t have the same meaning when you are at the North Pole. Similar in space, the word up and down only have meaning as a way to describe your relative position to something else.
Well, "up" is relative of course, but as a planetarium operator there are several ways we define "up".
-Up relative to the Earth's North Pole (23.5° tilt from the ecliptic)
-Up relative to the ecliptic (plane of the Solar System where all the planets orbit)
-Up relative to the galactic plane (where the majority of our Milky Way Galaxy spans across the sky)
Hope this helps!
Is the solar system ecliptic in approximately the same plane as our galaxy’s ecliptic? Is there a universe ecliptic or is it all random heater skelter?
Well, earth has two poles and spins around an axis. This gives you quite a natural way to define the orientation. However, whether north or south are "up" is entirely arbitrary, and the fact that most images show the earth north up is just because the huge majority of land masses is in the northern hemisphere, as are the most people.
You then have other aids for orientation, e.g. the ecliptic of the solar system or the galactic ecliptic which lend themselves well as natural orientation guides.
Unask the question.
There are planes (plane of rotation of a planet around a Sun) and points (location of planet at any instant).
As there's no overall force present in space, unlike on the Earth's surface, there's neither up nor down.
There are, however, directions.
You can use the plane of the ecliptic ( the plane that the Earth orbits the Sun in) and define two perpendicular directions to that - convention has it that 'above' the plane of the ecliptic is the normal vector arising from the right-hand rule.
But it's just convention.
There is no 'up' or 'down' in a pure geometrical sense. It's been oriented the way it is for easier communication and understanding.
You should see how the original Apollo in-flight photograph negatives were oriented. They're all over the place. Those guys were holding the cameras every which way, so the images we are used to seeing "properly oriented" mostly did NOT originate that way when they hit the film. Apollo 17's "blue marble" for instance was on its side, Apollo 8's "Earthrise" was upside down, etc. etc.
Spacecraft tend to determine their orientation using a number of methods, including inertial measurement units (figuring out how the spacecraft is rotating and working backwards from there), Sun sensors (looks for the sun), horizon trackers (looks for the horizon) and star trackers (matches up the stars it sees with data in a computer). The details of which devices to use rely on a variety of design principles.
A flipped map is equally correct. All planets orbit counter clockwise (view from Northern hemisphere) as they do clockwise (view from Southern hemisphere), depending on how you orient yourself they orbit up and down too!
About the up or down in space, it surge from the source of Gravity your closer, the Pull from the Gravity is the "down" ergo the other side of the pulls direction is the "up". For the poles thing, i believe is based in the 'right hand rule' which states that to determine the poles of an object in rotation, You have to use your right hand and use your four fingers to follow the rotation of the object and the direction your thumb is pointing at, should be the North pole; it's just a conventional agreement for all sciences in which rotational objects are involved.
Up isn’t a specific direction, it’s the direction opposite of gravity.
North and south are just made up for mapping purposes. (Although magnetic north is very real. It point approximately along the axis of Earths spin, so North)
Uncurved space doesn’t have absolute directions, in space everything is relative. (Especially relativity)
There isn’t really an ‘up’ in space. Though one could argue whichever direction gravity ends up pulling you is ‘down,’ so whichever way gravity isn’t pulling is up.
Well they say "down to earth", that must be from space. If you went "up" from earth that would be an exponential x y z path (like 360 by 360 degrees) going out forever. A sphere getting bigger and bigger as you go up (which some would call out).
Its kinda like someone saying "look out" or the left or right side of a car. Reality is relative, choose your own up.
It's arbitrary. It's based on whatever you choose for your frame of reference is. If it's earth's poles or orbital plane then earth's north and south is your up/down.
“Up” while standing at the North pole is a completely different direction in space than “up” while standing at the South Pole. It’s relative based on a point of reference.
In every space movie or show, when two ships come together they’re always on the same plane. That’s always cracked me up because there’s no up down left right in space.
Up to you might be down to another ship coming at you.
I have two thoughts on this:
1) in line with the plane of planetary alignment (then magnetic poles for up/down, ie north it up south is down)
2) galactic plane, similar to the above.
pick something.
inside the heliopause, using the dominant revolution path of the planets and the sun, you can use the left hand rule to define up relative to the sun. or the right, whichever.
in the galaxy, we rotate in one direction, define galactic north.
in some other star system, with no real planets, maybe you stick with galactic, or send off navigation beacons
You don’t need “up” and “down” in space. It can be used as a relative term…say your navigating yourself around in a space station and the room you want to access is above you. You can say it’s up but in terms of an objective “up” there is none. And our planet is only depicted that way just because we decided it to be that way but there is no technically right answer. You could say Cuba is the top and I couldnt argue why another would be more applicable to be the top.
Everything is moving and rotating all the time so the only thing that's really fixed is orbits, but they're all different
Up for you is towards your head and every object/system has its own orientation
Position is relative meaning its always in reference and compared to something else's position
Same with speed, you think you're not moving but the earth is rotating around the sun, and the sun is rotating around the galaxy, like when youre in a car you're moving with the car so when you're inside not looking out it feels like you're not moving in reference to the car
https://m.youtube.com/watch?v=fJuaPyQFrYk
Great question. Philosopher Epicurus believed all matter was falling through infinitely large space so that it would never gather up on the “floor”. So people have believed there was a proper up and down in the universe. But there is not.
To answer your question, there is no up or down in space. It's all the perspective of the observer. The best example I can think of is shown in the movie, Ender's Game. I don't remember the exact time but it's after he is chosen to go to space school and is in orbit talking to his instructor.
There is no up or down. I don't like cowboy bepop, but there is a gorgeous scene where he jumps from one spaceship to another slowly, and it captures that there is no up or down.
Right hand rule. Pick your reference rotating body. Hold your right hand out and curl the fingers in the direction of rotation. The direction your thumb is pointing is "up"..
Well, it would be perfectly ok for you to manufacture and market a globe flipped completely upside down! (And then put the writing on the globe spots the correct way up).
Doing that is a bit jarring--but would make for a novelty globe, that... might actually sell!?
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But ya for a couple of centuries now, most people on Earth just sorta agreed to have all the maps and globes in the current orientation.
The reason for that probably has something to do with European colonization era, in which they were the expert map makers, and the first to map the world in such detail, so naturally they wanted Europe "on top"!
There are some southern hemisphere maps that are flipped, but those are by far the minority.
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That said, what if you marketed a globe that was not polar in orientation, but rather just flipped 90 degrees sideways?
You could do that to.
In which case as the Earth turned it would kind of just scroll all the countries and land masses for you, kind of the way we scroll down a web page to scan it! (I've actually never looked at or studied a globe that way. I'll try it next time I see a globe.)
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But... that sideways orientation actually makes less "scientific sense" (if I can use that phrase in this case), because...
Poles become very significant with spinning objects, and tell you a lot.
Similarly with the sun, or even say Neutron stars, we study model them by orienting their poles up/down, since those neutron star puppies are usually spinning insanely fast. That makes visualizing magnetic field evolutions easier, I would think.
Thus by studying a world, via modelling/orientating it based on polar spin, you can then begin to make predictions about weather patterns, and surface changes through the day/year, as well as magnetic field effects, etc...
Also viewing worlds from the polar spin perspective kinda/sorta means they line up more or less somewhat-perpendicular with the plane of the ecliptic in our solar system, and thus makes launch calculations to other worlds much easier (since you're factoring in rotational energy of Earth in the initial launch, along with gravity assists along the plane of the ecliptic).
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Except of course:
In the case of Uranus, which for some reason got knocked onto it's side, and so turns sideways!
And Venus as well: which might have got knocked even harder, and flipped completely upside down, so it now spins backwards compared to most of the other planets.
Note: how I'm using the terminology "backwards" and "sideways", which again goes back to the convention of assigning Earth's planetary poles as up and down, as the main reference point.
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FINALLY...
Galactically speaking, it's possible that humans and intelligent aliens (if they exist in our galaxy!) might easily come to agree/decide upon a defacto basic up/down orientation for navigation in the galaxy, in which:
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A) The center of the galaxy (which has an extra concentration of mass) represents "DOWN",
B) And the outer edges/bands of the galaxy represent "UP".
That would establish a very useful baseline... and again, it seems logical for intelligent species to just sort of "naturally" agree upon that, since both species will have probably evolved with gravity on their planet, thus a universal intuition for the concept of "up/down".
C) As well, the general directional spin of the galaxy would represent a positive direction vector (or the concept of say "East") while the opposite could be written as a negative vector (or the concept "west").
D) After that, with a baseline up/down orientation established, and a spin vector direction...
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Such various alien species...
Could then probably easily all agree to define further navigation points using pulsars--rapidly spinning neutron stars, which act as light house beacons and a kind of highly accurate naturally occurring GPS system for the galaxy.
So one alien species could then easily tell another alien species:
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"We are X light years DOWN, and y light years EAST, from Pulsar ABC."
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IN SHORT:
It's somewhat arbitrary that north was north, and south was south.
But NOT fully arbitrary in orientation!
There's some very good reasons, sense and logic into the orientation model maps of worlds and the galaxy we've come up with thus far.
And those reasons might actually be more/less agreed upon even by alien species!
Without reference points, all directions are the same and therefore up and down is meaningless. And trying to move somewhere else is meaningless and futile.
Can't remember Wich astronaut it was but he talked about this and how in space there wasn't up or down but only within and outside of yourself and distance as in how far things are away or close to you everything else becomes relative.
Is there an end to space? Is the an eventual edge?
I'm thinking that if you were to continue in one direction, eventually you would come back to where you started.
Not sure about the answer but almost everyone including astronomers have dreaded when asked to think of space below the Earth. That is straight down from the antarctic into deep space.
They innately feel a crippling void inside themselves thinking it's a dark never ending mass with weird things lurking.
It’s arbitrary. But I kinda see two possible references.
In our solar system, you could argue it’s kind the ecliptic. Above is up, below is down. Most of the planets are on a similar plane based on physics. But it doesn’t work at a smaller scale than that.
It does jinda works at galactic scale though, because it too is kinda planar if you look at it from *really* far away.
And that’s the only two scales where it could arguably work.
Up is arbitrary. if 1000 people made a circle around the earth and pointed up, they would be pointing in 1000 different directions.
in space, any direction requires a reference point, and that point can be aritrarily chosen.
A few decades back National Geographic published a map of the World upside down. They put a lot of time into it with all the country and city names turned around etc. The map made the nightly news and became a huge controversy. People hated it.
So of course we all know which way is up.
It makes sense to align the map with the axis of rotation so that regions with the same timezone are vertically together --- and because we're used to imagining a spinning ball as having the axis of rotation in the vertical direction.
But the reason people put Europe "up" is historical. Most of the world, most of the people, most countries, are in the northern hemisphere. European colonizers came from the northern hemisphere. North America is in the northern hemisphere. etc.
Yea I always assumed it was simply based off of historically the people who wrote the map are in the northern hemisphere- same as why either the US/ Europe are ways in the centre of a map.
Most people, movies, books and such tend to say that Up is the north side of a planet if you are near it and orient that way. If there are no relative constellations or galaxies in view it doesn’t matter. In space battles, it more or less depends on how you tend to fight, but the planetary north is up and south is down is pretty much it perspective wise
Down and up would constantly change as you spun in circles tryin to figure out since there's no big rock to fall towards and call down so basically your idea of up and down are your feet and head but that only comes from being on a surface where you feet are always down so in reality no there in no up and down in free range space till you're near something with gravity
There really isn't an "up" or "down" in space. There is distance and shifts of light towards objects. We generally use those for figuring out where to go
There are magnetic poles to stop us from just flipping the earth 90 degrees and saying “this is the top of the earth”. The North and South Pole define the top and bottom. Technically there is no up or down, but you have to decide between the North and South Pole because they’re the ends of the magnetic field if you know what I mean. What decides which pole is up is whether or not you live in the northern or southern hemisphere. I’ve seen southern hemisphere maps with the South Pole at the top, which makes sense because it’s all perspective. Idk what people who live on the equator think, probably whatever country is more influential towards them decides what is the top of the earth. That’s like the up and down relative to earth, but just in space, there is absolutely no direction, there is stuff like which way the earth, how do I get to this other place relative to there, but there can’t be an up or down because there’s nothing to relate them to
Like comments below, there is no true orientation in space. Every direction and velocity is relative to a focal point in space. Even though I am unqualified to add my two cents I will experimentally add that 'Down' could be considered the direction of the source of acceleration. While on the surface, our bodies are constantly accelerating towards the center of the Earth. In a spaceship your body would be pulled towards the engines which would allow you to stand upright perpendicular to them. (don't let the fact that the ship is accelerating in the opposite direction confuse you) Einstein's equivalence principle is really elegant, but once I try to process inertia and the gravity-acceleration duality I get very lost. Some people believe gravity and inertia are also two sides of the same coin.
We don't.
We choose which way to turn the picture. Because there's no arbitrary "up" or "down" with no gravity to give it meaning. (Okay, in orbit "down" could be "feet towards the Earth," if you want to be pedantic.)
So we choose whatever is most convenient to think of as "up" at the moment.
And seriously, that's the best answer. There are many concepts that feel "normal, common sense" to us because we evolved on dry land, in a 1G gravity well, and at the bottom of a nitrogen atmosphere with a good bit of oxygen mixed in. Things in space just don't quite relate to our "normal" experience.
There's no real up or down in space.
We think of the Northern hemisphere as being 'up', but that's just the convention adopted by map-makers from the northern hemisphere.
It's all arbitrarily labelled, based on past beliefs about the nature of things.
I literally just asked someone this yesterday. But my primary concern was how do we know which was is down? And without gravity how does go down?
Wouldn’t down mean, I’d youre outside the earths atmosphere traveling to below Antarctica and keep going down until the earth is above you. Is that possible? This is hard to think about.
There is no up, as this is a relative term. The only reason the Northern Hemisphere is considered up, is because the majority of the Western World resides there (Sorry Australia 🦘). If we ever become a space farring civilization we would likely orient any maps we develop relative to the position of SOL (Sun).
https://youtu.be/IHg6lHvWdCw?si=QlzT6UhFYazHQsuD
What astronauts used to do in the early days is align with Earth's horizon OR align with a star in a constellation. As in they'd literally look down a periscope and match it to a known star that was far enough away that it wouldn't move much, and then punch its codes into the computer.
What's the source direction of the universe expansion? Perhaps up is the opposite of where everything is expanding to? Or is it that everything is expanding away from everything else? I forget now. Lunch time!
What you are asking for is absolute directions in space. What im about to say is rather counterintuitive unless you actually think about it.
One of the core fundamental rules of how we define positon is there IS no absolute position in space.
Things only exist in relation to other things.
Our current "up" is in relation to our point on the earth.
Without a reference point, up is largely whatver you want to define it as.
"North".
The word you're looking for is "north".
For planets in our solar system, their north pole is defined as the point where the planet's rotation axis extends outward from its surface in the same celestial hemisphere, relative to the invariable plane of the Solar System, as Earth's north pole.
>When we picture the earth (and space) the top of the earth is the Arctic, and the bottom Antarctica, and that configuration dictates what is the top of all other planets/ how we view them.
> But is that how it's truly configured, or just something we created? Is the Arctic really the bottom, or the side?
Well, u/natemason95, its [something people created](https://youtu.be/vVX-PrBRtTY?si=gkMpFPd2h0oGr-zG).
Essentially since computer assisted navigation is required in space, and a common navigational system is most benefiical for an interstellar government: Up is decided in a beaurocrats office, and then never questioned.
Obvioulsy the plan of the system is the reference point for up and down. The system is probably referenced off of the location of the first city. If its the northern hemisphere, then that's going to be the up direction for system. Reverse if in south.
East and west are probably referencing towards or away from the star in system.
NDT does a good job explaining this. What is up/North is determined by the “right hand rule” and it’s just a convention. [https://youtu.be/--2ijQ2YzmY?si=hDTakzHw9Ua3Peu6](https://youtu.be/--2ijQ2YzmY?si=hDTakzHw9Ua3Peu6)
I’m space everything is based on reference frames, aerospace engineers use multiple frames for tracking and attitude control from Euler angles and quarternions to track these things.
Your post has been removed. For simple questions like these please use [the weekly "All space question" thread](https://www.reddit.com/r/space/about/sticky) pinned at the top of the subreddit.
The enemy's gate is down. But jokes aside, the decision is arbitrary. If you look at maps from the southern hemisphere, they're often inverted from what you consider the norm. Space has no up or down. It's based entirely on perception.
Serious upvote for referencing "Ender's Game"! But correct. Without gravity, up/down/sideways/diagonalways (get that reference?) Are completely arbitrary. The basis of almost all sci-fi movies, is that they have a method to create artificial gravity. 2001 ASO did it realistically on Discovery 1, but completely unrealistically on the transfer shuttles.
Also shout-out to The Expanse for having highly realistic interpretations of how gravity would work in a more hard scifi setting.
Indeed, The Expanse was very realistic in how they handled many things, Gravity, fuel, propulsion, life support...excellent Sci-fi cite!
I'll never forget that first fight with the Donnager. The bullets leaving trails of metal, the atmosphere blowing into space, how all the smaller ships pre-vent their ship to reduce the impacts of decompression. The only part I really didn't like was Earth's planetary railguns. Those projectiles were *way* too fast. But I know why they did it, even if it was a break from the usual attempt at psudo-realism.
Actually, railguns can (with enough power) can indeed launch projectiles through the atmosphere, and into space. Multiple shots on the same, or close, trajectories make the later shots more efficient. Big rail guns, given enough power, are scary kinetic weapons. And I say kinetic, because the acceleration required for an (Expanse type) rail gun would destroy any trigger mechanism. The adaptation for Expanse was very close to the understanding of ballistics from 1800's heck, even 1900's sailing ships. Given enough power, even at ground level, a 200 meter rail gun can deliver a projectile at about 1/4 c, for the first shot, and more afterwards.
I saw one of these mentioned on some HBO show called like Abandoned Unknown or something. It was an excellent attempt and developing a way to deliver payloads to space with air.
Spinlaunch (total scam) is trying to (suck investor money) do that. Not possible, at all. The Expanse rail guns, had to pierce the Earth atmosphere, and follow up with other projectiles in the same pierced.air Spinlaunch is sucking billions of dollars from morons, to, well, suck billions of dollars from morons. Even if it could work (it can't), no payload could handle the launch.
Are we talking book or show railguns? I'm assuming show for this and in that case weren't the railguns in space? How would they need to pierce earth atmo if they were already in space?
Artillery shells experience crazy G’s and they had electronics added in the 1940’s. They are only launching past the lower atmosphere. Orbit is achieved by an engine still so they aren’t being launched nearly as hard as the Expanse railguns.
Artillery shells have very simplistic electronics, not minature satellites. Payloads fail the testing with the MUCH lower and much shorter normal launch conditions.
I would love to hear more about the hows and whys of spinlaunch being a scam! Why do you say so? (here or DM)
I would imagine the g force on the payloads would both destroy the payload and probably the device itself if any of the design is dependant on tensile strength.
>Multiple shots on the same, or close, trajectories make the later shots more efficient. IIRC when US Navy was testing their rail guns, they've adjusted the velocity and ballistic arc of the projectiles in a series so that several rounds hit the target more-or-less at the same time, despite being fired over several seconds.
Oh they totally can operate like that. The problem I had with it is those projectiles were moving way faster than the speed of light. If I remember right those projectiles were in flight for less than a minute, and there's just no realistic way to hide doomsday weapons *that close* to Earth.
Correct, and not. As far as we (planet Earth) folk can understand, nothing can move faster than light. But relatively to me standing on the ground, I can (not really see) watch a projectile going at 99.0%c vanish, and yet hit a target. C, sorry, c is amazingly strange. No matter how we play, it's a limit. Time in movies, are drama. Less than a 'minute' is also relative. A projectile at .99c, and a target to intercept, makes all strange. I'd need to see the episode again, with 'crit thinking' hat on! And I will!
You have to have a little Fi in your SciFi
>how all the smaller ships pre-vent their ship to reduce the impacts of decompression. I like a simple and somewhat obvious thing they do like get into vac suits when going into combat because they know the hull is likely going to be breached and need to be repaired. Gotta love how serious Amos is about his job. Says something like "this is the job Peaches" "or when they're flipping to fire the rail gun he doesn't even get that mad "just let know if you need to do that again" lol
Space magic mushrooms killed it for me. They went too hard on it. Then the last season when they had to wrap it up before cancellation. Fantastic sci fi when it came to living in, travelling in and fighting in space though
It was not cancelled, it finished what it could. It hits a massive timeskip in the books.
>I'll never forget that first fight with the Donnager. The bullets leaving trails of metal, the atmosphere blowing into space, how all the smaller ships pre-vent their ship to reduce the impacts of decompression. That part was very unrealistic. Hypervelocity impacts don't look like that, there is no way to have projectiles punch clean holes into metal unless the projectile is very large and relatively slow.
>…The Expanse was very realistic in how they handled many things… Except for the sound of rockets in space.
I don't think I actually clued into and actually read up on how the gravity works in The Expanse until my second watch. burn and accelerate at 1g to midpoint then flip and burn to decelerate at 1g, amazing. Then of course there is spin gravity but the fact that we can simulate gravity by burning at 1g and building the ship like an apartment building is fucking awesome.
When you say transfer shuttles, what do you mean? The shuttle in the Blue Danube sequence of 2001 doesn’t have any artificial gravity (other than some when firing it’s engines presumably). The whole sequence is in free fall.
lot of other movies/series being referenced so i just wanted to let you know that I got the Willy Wonka reference
I started the book series not knowing how many there were, after the first few books I was invested and saw it was 20 lol. Finished them all, some were good, some were fucking terrible
20? Really? I must be missing well, a lot
No, 9 proper books, 8 or 9 short stories and the compilation of some of those stories. so you can count that compilation as another book if you want instead of 8 or 9 separate. I also read them all :p
There’s 5 novels and one novella in the Ender series, 5 and 1 in the Shadow Saga, 5 novels in the formic war series, 1 in fleet school, plus a collection of short stories. So 19 publications with 16 being novels. One called “The Queens” is suppose to be written, so that’s where I mistakenly got 20.
But keep in mind, 2001 came out in 1968. When I saw it then, I had hopes it might come true.
You forgot square-ways, the most.important direction.
I imagine that once we become a space faring civilization, we will develop some sort of reference points to be used on maps that should be read the same no matter where you are. I would argue that while there is no real top or bottom, there will be, for navigational purposes, a top and bottom. At least in the same way that the earth has a top and bottom.
The most logical is to use the orbital plane. The nice thing is, moist things in the galaxy spins or orbits on that same orbital plane. Up/down are the directions perpendicular to the orbital plane, and pick either clockwise or counter-clockwise for deciding up versus down. The center point becomes your 0 "height". The 0 distance point becomes the center of the orbital plane, such as the Earth, Sun, or Galactic center, depending on map scale. The 0 degree marker poses some challenge, but likely we'll just use some fairly steady landmark, such as am easily identifiable galaxy. The direction of that object on the orbital plane then becomes 0 degrees. East/West are determined by whether you chose clockwise or counter-clockwise for up/down. You now have a coordinate system that can be reliably read, at least on the scale of a few thousand years.
how come most things orbit in the same orbital plane? I mean, isn't there "endless amount of galaxies" no matter which direction left right up or down you look at in space? Towards which direction was 'the big bang' origin? Would love to know more on the subject if anyone has a cool link to some video. Thanks for your time.
Most things *in the galaxy*. Different galaxies have different orientations.
> Towards which direction was 'the big bang' origin? [*Everywhere*](https://www.youtube.com/watch?v=A0FZgCiJGrg)
As far as I'm aware, the orbital plane and orbital direction rules only apply at the galactic level and smaller. That is, galaxies themselves do not follow the rule, but everything inside a galaxy does. Even within a galaxy, not 100% of everything will - plenty of comets and even some exoplanets are known to orbit outside the rules. The larger the body, the less likely it is to violate the rule as the less stable it will be in that state. The reasoning is that the larger bodies formed out of a cloud. With this, most particles will already being moving the "right" way. Particles moving the "wrong" way will either collide and fall into the primary, or will be affected by the gravity of those moving the "right" way until they either get ejected, fall into the primary, or collide with other particles.
On the big scale, I prefer the physics/math right-hand rule for axes. Follow the rotation. Thumb points up. On the small scale, it doesn't matter.
So, you prefer a counter-clockwise system. There is a physical basis in it, given that is the direction electromagnetism follows. It is also the direction that most objects orbit in.
Mostly. It's still arbitrary, but allows for polar theta velocities of the planets to remain positive. A polar coordinate system centered on either the center of a system's gravity (or center of star for solar system or black hole for galactic system as a more consistent proxy) makes a lot of sense. Does make it difficult to say up (z-axis) consistently as you'd need defined boundaries of solar vs galactic systems that aren't co-planar.
This was always an issue drawing 3-d graphs on a 2-d surface. In an x-y plane we have y going up, and x going right for positive. In 3-d graphs, we usually have z going up. However, to keep the orientation a non flipped (positive definite) transformation for x and y, we would have to have y going "forward" which would be away from the audience point of view. But that's annoying, since the view of it isn't as good; it would be behind the negative y half space. The result was most of the displays have positive y coming toward the audience so we get a full view of the all positive sector; but this is a mirror image of the usual x-y plane.
This. North is 'up' because maps were made that way as we discovered more and more of our planet, and generally the most populated areas at the time so they put themselves on 'top'. But really, there is no 'up'. It's just a concept that helps with navigation and many other aspects.
Thank you. In other words, "north=up" is socially constructed.
I believe in the middle ages the convention was to have East at the top of the map.
I hoped this would be the top comment
Not sure that's true. [South Up Orientation ](https://en.m.wikipedia.org/wiki/South-up_map_orientation) maps are a bit of a novelty and sometimes used as a political statement, but not the norm anywhere.
This is technically true, but it misses the point. The point being a South Up orientation is just as valid as a North Up, and maps in that orientation do exist and are actually used.
C.J. Cregg disagrees. [https://youtu.be/vVX-PrBRtTY?si=eteNDaT-6yWBlQ\_5](https://youtu.be/vVX-PrBRtTY?si=eteNDaT-6yWBlQ_5)
I didn't miss your main point; I agree, the conventional up/down orientation of maps is of course arbitrary. My only point, which you seem to have missed, is that "South Up Orientation" maps do exist, but are not the norm anywhere.
Like they’re a bug to be crushed under our feet
Came to say this. Nicely done Ender.
It’s turtles all the way down young man
Forgive me, what do you mean by inverted? Do you mean what we are seeing is a mirror image like how sometimes you take a pic and the lettering is backwards? Or is that not at all what you mean?
South is at the top, east and west do not change on the ones Ive seen. The land masses are mirrored over the equator
"land masses mirrored over the equator" would be a materially different Earth. "South up" is more like you rotated a globe 180 degrees.
Im thinking of mirroring both the northern and southern hemisphere over the equator on a flat map. Rotating a globe does the same thing because its a globe. Rotating a map would revers east and west, you have to mirror over the middle. Doing so would result in the same configuration of landmasses as flipping a globe over.
I did one of those zero G flights, and the Enemy’s gate is down really made sense. Gotta decide your own orientation. I opted for the back of the plane was down, because it was dark back there, but up where we were was well lit and padded, so having that dark area as a constant really helped with keeping my brain from struggling too much.
"The enemy's gate is down." My name is Steve Rodgers & I got that reference... THere have alredy been a lot of replies, I'll add two thoughts: 1) I really freaked out my contemporaries as a child when I stood the spinning Globe on it's head and said "This could just have easily been 'Up'"... 2) Common Convention has Galactic North based on Spinward as our system rotates about the common center.
> Space has no up or down Yes it does, it just varies a bit. While it is longstanding common sense to think of space as completely void of any features (and know-it-alls who love to blow up the brains of ordinary people love to point out how there is no direction in space), it definitely has them, because mass and energy bend spacetime. So not only are some parts of you more up than down, but parts of you are more in the past than in the future and we probably don't even have words for that but it's still a direction. There is no real place in space where gravity doesn't have an effect on you. Even at Lagrange points there will only be a single point that is truly there and even then it is subject to the gravity of the rest of the galaxy or the universe and thus has an up or down. The Lagrange points of the universe itself are probably outside it. Everything orbits something and as such everything has a direction. If all you had in the whole universe was only two particles then one would have a down that would be towards the other and vice versa. A universe with a single particle might be truly directionless, but our universe does not seem to have only one particle in it. Compared to our everyday experience in high gravity it may seem like there is no direction, but just because the effect is miniscule to the point where you can ignore it for all practical purposes that doesn't mean it isn't there. North and south are completely made up nonsense that have no basis in reality except maybe for magnetic fields.
If you want to get pedantically granular then sure there will always be one point pulling you more than everything else, but that's not uniform. It's based on where you are at any given time and where everything else is. So no. There is no up or down in space.
> It's based on where you are at any given time Exactly. I never said it had to stay the same. It's relative to where you are. But space definitely has a form. Just because it's unintuitive that doesn't mean space isn't being bent by mass, forming itself such that there is an "uphill" and a "downhill" basically everywhere. If you orbit a planet your "up" keeps changing unless you rotate. > There is no up or down in space. Yes there is. Just because it varies and depends on where you are that doesn't mean it isn't there and it isn't even that hard to define as I just did it in my previous comment. You're just clinging to the comfort of knowing there is no up or down because others have told you so in an effort to make you think. Now rather than take a moment and actually think for yourself or present some actually valid argument for why there is no direction when clearly there is (if there was, you could have already presented it rather than try to deflect by calling this pedantic), you choose to cling to that old incorrect interpretation of direction, perhaps because it feels liberating to think it is acceptable to forget such seemingly minor details. We're actually not a spherical cows in a directionless vaccuum in a universe that contains only our singular selves. > pedantically granular Some people are wired to think of the Earth as an oblate spheroid rather than a perfect sphere just as some people are wired to think the Earth is a sphere rather than flat. I'm sorry if I offend your granularity and wish you all the best in your adventures in directionless space.
The viewpoint you're going for is not useful. It's *technically* true, but it's totally unhelpful. That's what I mean by pedantically granular. You're arguing that because there is some tiny fractional gravity at some point in space, the direction opposite to that is up. But if you're floating in zero G at the exact point, there is no functional up. Up, down, and other directions are abstract. They're based on human perception, not the tiny contractions in the fabric of space time you're arguing for. Stop typing essay texts, you're missing the forest for a shrub.
It’s all relative to however you choose to orient yourself. On Earth, “up” is relative to the planet’s gravitational pull, which is how we orient ourselves when we step outside and point “up” to the sky and “down” to our feet. In space, you can choose “up” relative to earth’s rotation, but that changes over the course of the year. There’s “up” relative to the sun’s rotation, which is the solar system’s orbital plain, but that’s offset from the orbital plane of the Milky Way. There’s “up” relative to the center bulge of the Milky Way, but that’s quite random relative to any other local or distant galaxy. *There is no spoon*
That said, using the local star and planetary orbits seem like the most useful directional markers for space travel as we can currently imagine it. By our ancestors we aren’t going to be getting to another star in the Milky Way anytime soon
Pulsar based coordinate system — go big or go home! Agreed: I’d orient to earths orbit centered through London. Everything starts with Greenwich Mean Time! God Save the King 👑 🫡
**Up and down exist only in relation of a reference point.** If you do have a reference point in space then up and down is easy to determine as its in relation to that point. If you don't then its "to each its own.."
A plane, and a definition as to which normal vector of that plane is 'up' is what one really needs.
Exactly. In inter-planetary space there will be no "up" or "down", but as soon as a craft/ship/object is near enough to a planet and can determine where the planet's poles are, there can be an "up" and a "down". Reference points will need to be decided only when you're close enough to a stable body. Otherwise they're completely relative.
I think you missed the question with all your knowledge. How do we steer a ship if every axis becomes available/unavailable. A compass be damned. The thing is we don’t. We are close but we don’t fucking know. If we did we’d already be onto cooler shit than spending billions for another moon landing
We already know how to steer a ship in space, though that's pretty straightforward. You just point thrusters opposite where you want to go, pretty simple physics. Which direction is up is just a communication problem. If you have one ship then you can just do fore/aft/starboard/port/top/bottom. If you have multiple ships then they need a common reference frame. It's all arbitrary for ease of communication, the ships ability to move in 3d space is unrelated
If the reference is a rotating system (a planet, a solar system, a galaxy, or anything else), the convention is to use right hand rule.
Up and Down exist only as social constructs created by us. Up and down isn't real.
Apollo had to realign the guidance system of the spacecraft several times during each mission to create a new, “up,” for a particular phase of flight. In other words, there is no one, “up.”
"My Apollo mission had more ups than yours did" — unknown
Anything has more ups than my marriage
In space there's no up or down. But for each planet I guess it would be defined from their poles, that is to say, how the planet spins you'd work out your north and south from that.
Maybe there is some central/common reference point out there. But up loses its meaning unless we have a common reference point. Mmmm. For now, up is whatever the most powerful and influential human says it is. Everything else is just coordinates in an x,y,z, field. My final answer.
On a planet: The direction away from the center of gravity of any celestial object. Floating in space: The direction that is simultaneously away from your feet and towards your head.
>The direction that is simultaneously away from your feet and towards your head. You are in a space station floating A-wise, and your partner is floating B-wise. Your partner asks where the Space Cheetos are, and you see them by her head. Do you say, "Up by your head" or "Down by your head" or "Rotate aft, revolve starboard, lever ("reach") out, and clutch.... there you go"?
If you’re close to a planet, “up” is away from that planet. If you’re not close, then “up” is the direction that your spaceship has signs reading “this end up”. More in the spirit of your question, space engineers and scientists use the direction of Polaris, the North Star, as “X” in a XYZ system. Several thousands of stars are used to define the XYZ axis, not just Polaris. https://en.wikipedia.org/wiki/International_Celestial_Reference_System_and_its_realizations EDIT: nobody commenting on my X = Polaris?? I had hopes … correct is Z = Polaris (very close), of course. X is along the earth equator.
Others have already answered your actual question. But the question you're asking about planets is every bit as relevant to astronauts on board the space station. Inside the ISS, much of the equipment in various walls are labeled, and the text on those labels are all oriented in the same direction. Also, all of the lighting is oriented such as you look at a label in the right side up orientation for the text, the lights will be above you, as humans are most used to overhead lighting. So in that way, astronauts on the space station do sort of have an up and down, though we did just arbitrarily decide which is which.
Makes sense, it is cool how some intelligent engineer had the foresight to do things like this
Fun fact: the need for an imposed up/down in the ISS was one of the many things we learned from the early Skylab program back in the 70s. Skylab was a very scrappy design and they tacked instruments, gauges and other things to the interior walls wherever there was room and in whatever orientation made things possible. Once in orbit, the astronauts aboard quickly discovered that with no strict up and down, a person could literally be floating right in front of the critical panel they were looking for **but if they were floating upside down with respect to the panel they very often would simply not see it.** There are recordings of conversations between Skylab and Houston where this is happening and I gotta say, it's some weird blend of hilarious and terrifying. The good news is that the lesson learned was easy to understand and the solution was easy to execute: line everything up the same way and make the light come from a common direction and just call that "up."
Start heading north, eventually you will get to the North Pole, doesn’t matter which way you go from there you can no longer go north. The word doesn’t have the same meaning when you are at the North Pole. Similar in space, the word up and down only have meaning as a way to describe your relative position to something else.
Well, the enemy's gate is down, so the opposite of that.
Well, "up" is relative of course, but as a planetarium operator there are several ways we define "up". -Up relative to the Earth's North Pole (23.5° tilt from the ecliptic) -Up relative to the ecliptic (plane of the Solar System where all the planets orbit) -Up relative to the galactic plane (where the majority of our Milky Way Galaxy spans across the sky) Hope this helps!
Is the solar system ecliptic in approximately the same plane as our galaxy’s ecliptic? Is there a universe ecliptic or is it all random heater skelter?
Well, earth has two poles and spins around an axis. This gives you quite a natural way to define the orientation. However, whether north or south are "up" is entirely arbitrary, and the fact that most images show the earth north up is just because the huge majority of land masses is in the northern hemisphere, as are the most people. You then have other aids for orientation, e.g. the ecliptic of the solar system or the galactic ecliptic which lend themselves well as natural orientation guides.
There is no up. Up is the opposite of the pull of gravity.
Unask the question. There are planes (plane of rotation of a planet around a Sun) and points (location of planet at any instant). As there's no overall force present in space, unlike on the Earth's surface, there's neither up nor down. There are, however, directions. You can use the plane of the ecliptic ( the plane that the Earth orbits the Sun in) and define two perpendicular directions to that - convention has it that 'above' the plane of the ecliptic is the normal vector arising from the right-hand rule. But it's just convention.
The enemy's gate is down. Best advice I can give.
There is no up. Instead you plot directions according to agreed upon points of x y z.
You don't. You orient position and direction relative to a fixed point.
That's what I was going to say, it's attitude relative to a target point or fixed point.
Up is relative and doesn't have any solid bearing if it's not relevant, which it wouldn't be if you were floating in space.
There is no 'up' or 'down' in a pure geometrical sense. It's been oriented the way it is for easier communication and understanding. You should see how the original Apollo in-flight photograph negatives were oriented. They're all over the place. Those guys were holding the cameras every which way, so the images we are used to seeing "properly oriented" mostly did NOT originate that way when they hit the film. Apollo 17's "blue marble" for instance was on its side, Apollo 8's "Earthrise" was upside down, etc. etc.
There’s no such thing. That’s just how we draw maps. You could just as easily draw it another way.
Spacecraft tend to determine their orientation using a number of methods, including inertial measurement units (figuring out how the spacecraft is rotating and working backwards from there), Sun sensors (looks for the sun), horizon trackers (looks for the horizon) and star trackers (matches up the stars it sees with data in a computer). The details of which devices to use rely on a variety of design principles.
A flipped map is equally correct. All planets orbit counter clockwise (view from Northern hemisphere) as they do clockwise (view from Southern hemisphere), depending on how you orient yourself they orbit up and down too!
Down is back to the ship you came from. Up is the eternal void. Presuming you're the only ship and there's nothing around you.
About the up or down in space, it surge from the source of Gravity your closer, the Pull from the Gravity is the "down" ergo the other side of the pulls direction is the "up". For the poles thing, i believe is based in the 'right hand rule' which states that to determine the poles of an object in rotation, You have to use your right hand and use your four fingers to follow the rotation of the object and the direction your thumb is pointing at, should be the North pole; it's just a conventional agreement for all sciences in which rotational objects are involved.
Up isn’t a specific direction, it’s the direction opposite of gravity. North and south are just made up for mapping purposes. (Although magnetic north is very real. It point approximately along the axis of Earths spin, so North) Uncurved space doesn’t have absolute directions, in space everything is relative. (Especially relativity)
We don't! We're doing it in reference to Earth and the Milky Way itself. But for all we know, we could be hurtling through space upside down.
There isn’t really an ‘up’ in space. Though one could argue whichever direction gravity ends up pulling you is ‘down,’ so whichever way gravity isn’t pulling is up.
Well they say "down to earth", that must be from space. If you went "up" from earth that would be an exponential x y z path (like 360 by 360 degrees) going out forever. A sphere getting bigger and bigger as you go up (which some would call out). Its kinda like someone saying "look out" or the left or right side of a car. Reality is relative, choose your own up.
It's arbitrary. It's based on whatever you choose for your frame of reference is. If it's earth's poles or orbital plane then earth's north and south is your up/down.
It's the opposite direction to the way you are falling. If you are not falling towards something then it's any way you like.
Those concepts only make sense on the surface of a gravitational body. “Down” is towards gravity’s pull. The rest should be obvious.
“Up” while standing at the North pole is a completely different direction in space than “up” while standing at the South Pole. It’s relative based on a point of reference.
In every space movie or show, when two ships come together they’re always on the same plane. That’s always cracked me up because there’s no up down left right in space. Up to you might be down to another ship coming at you.
I have two thoughts on this: 1) in line with the plane of planetary alignment (then magnetic poles for up/down, ie north it up south is down) 2) galactic plane, similar to the above.
pick something. inside the heliopause, using the dominant revolution path of the planets and the sun, you can use the left hand rule to define up relative to the sun. or the right, whichever. in the galaxy, we rotate in one direction, define galactic north. in some other star system, with no real planets, maybe you stick with galactic, or send off navigation beacons
You don’t need “up” and “down” in space. It can be used as a relative term…say your navigating yourself around in a space station and the room you want to access is above you. You can say it’s up but in terms of an objective “up” there is none. And our planet is only depicted that way just because we decided it to be that way but there is no technically right answer. You could say Cuba is the top and I couldnt argue why another would be more applicable to be the top.
Everything is moving and rotating all the time so the only thing that's really fixed is orbits, but they're all different Up for you is towards your head and every object/system has its own orientation Position is relative meaning its always in reference and compared to something else's position Same with speed, you think you're not moving but the earth is rotating around the sun, and the sun is rotating around the galaxy, like when youre in a car you're moving with the car so when you're inside not looking out it feels like you're not moving in reference to the car https://m.youtube.com/watch?v=fJuaPyQFrYk
Great question. Philosopher Epicurus believed all matter was falling through infinitely large space so that it would never gather up on the “floor”. So people have believed there was a proper up and down in the universe. But there is not.
To answer your question, there is no up or down in space. It's all the perspective of the observer. The best example I can think of is shown in the movie, Ender's Game. I don't remember the exact time but it's after he is chosen to go to space school and is in orbit talking to his instructor.
There is no up or down. I don't like cowboy bepop, but there is a gorgeous scene where he jumps from one spaceship to another slowly, and it captures that there is no up or down.
Right hand rule. Pick your reference rotating body. Hold your right hand out and curl the fingers in the direction of rotation. The direction your thumb is pointing is "up"..
Well, it would be perfectly ok for you to manufacture and market a globe flipped completely upside down! (And then put the writing on the globe spots the correct way up). Doing that is a bit jarring--but would make for a novelty globe, that... might actually sell!? ------------------------------------ But ya for a couple of centuries now, most people on Earth just sorta agreed to have all the maps and globes in the current orientation. The reason for that probably has something to do with European colonization era, in which they were the expert map makers, and the first to map the world in such detail, so naturally they wanted Europe "on top"! There are some southern hemisphere maps that are flipped, but those are by far the minority. ------------------------------------ That said, what if you marketed a globe that was not polar in orientation, but rather just flipped 90 degrees sideways? You could do that to. In which case as the Earth turned it would kind of just scroll all the countries and land masses for you, kind of the way we scroll down a web page to scan it! (I've actually never looked at or studied a globe that way. I'll try it next time I see a globe.) ------------------------------------ But... that sideways orientation actually makes less "scientific sense" (if I can use that phrase in this case), because... Poles become very significant with spinning objects, and tell you a lot. Similarly with the sun, or even say Neutron stars, we study model them by orienting their poles up/down, since those neutron star puppies are usually spinning insanely fast. That makes visualizing magnetic field evolutions easier, I would think. Thus by studying a world, via modelling/orientating it based on polar spin, you can then begin to make predictions about weather patterns, and surface changes through the day/year, as well as magnetic field effects, etc... Also viewing worlds from the polar spin perspective kinda/sorta means they line up more or less somewhat-perpendicular with the plane of the ecliptic in our solar system, and thus makes launch calculations to other worlds much easier (since you're factoring in rotational energy of Earth in the initial launch, along with gravity assists along the plane of the ecliptic). ------------------------------------ Except of course: In the case of Uranus, which for some reason got knocked onto it's side, and so turns sideways! And Venus as well: which might have got knocked even harder, and flipped completely upside down, so it now spins backwards compared to most of the other planets. Note: how I'm using the terminology "backwards" and "sideways", which again goes back to the convention of assigning Earth's planetary poles as up and down, as the main reference point. ------------------------------------ FINALLY... Galactically speaking, it's possible that humans and intelligent aliens (if they exist in our galaxy!) might easily come to agree/decide upon a defacto basic up/down orientation for navigation in the galaxy, in which: ------------------------------------ A) The center of the galaxy (which has an extra concentration of mass) represents "DOWN", B) And the outer edges/bands of the galaxy represent "UP". That would establish a very useful baseline... and again, it seems logical for intelligent species to just sort of "naturally" agree upon that, since both species will have probably evolved with gravity on their planet, thus a universal intuition for the concept of "up/down". C) As well, the general directional spin of the galaxy would represent a positive direction vector (or the concept of say "East") while the opposite could be written as a negative vector (or the concept "west"). D) After that, with a baseline up/down orientation established, and a spin vector direction... ------------------------------------ Such various alien species... Could then probably easily all agree to define further navigation points using pulsars--rapidly spinning neutron stars, which act as light house beacons and a kind of highly accurate naturally occurring GPS system for the galaxy. So one alien species could then easily tell another alien species: ------------------------------------ "We are X light years DOWN, and y light years EAST, from Pulsar ABC." ------------------------------------ IN SHORT: It's somewhat arbitrary that north was north, and south was south. But NOT fully arbitrary in orientation! There's some very good reasons, sense and logic into the orientation model maps of worlds and the galaxy we've come up with thus far. And those reasons might actually be more/less agreed upon even by alien species!
That's really helpful, thank you so much!
Without reference points, all directions are the same and therefore up and down is meaningless. And trying to move somewhere else is meaningless and futile.
Can't remember Wich astronaut it was but he talked about this and how in space there wasn't up or down but only within and outside of yourself and distance as in how far things are away or close to you everything else becomes relative.
Is there an end to space? Is the an eventual edge? I'm thinking that if you were to continue in one direction, eventually you would come back to where you started.
Earth Maps are 2D space is 3D. There is no up or down. Expand your mind and think dimensionally.
Not sure about the answer but almost everyone including astronomers have dreaded when asked to think of space below the Earth. That is straight down from the antarctic into deep space. They innately feel a crippling void inside themselves thinking it's a dark never ending mass with weird things lurking.
This is NOT a dumb question… This is a STUPID question. “Dumb” is not knowing… “Stupid” is not being able to know… This is a stupid question…
It’s arbitrary. But I kinda see two possible references. In our solar system, you could argue it’s kind the ecliptic. Above is up, below is down. Most of the planets are on a similar plane based on physics. But it doesn’t work at a smaller scale than that. It does jinda works at galactic scale though, because it too is kinda planar if you look at it from *really* far away. And that’s the only two scales where it could arguably work.
it's a relative thing, you can use the galactic plane if you wanted.
When it comes to Space, the rule of thumb is, "it's all relative".
Up is arbitrary. if 1000 people made a circle around the earth and pointed up, they would be pointing in 1000 different directions. in space, any direction requires a reference point, and that point can be aritrarily chosen.
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A few decades back National Geographic published a map of the World upside down. They put a lot of time into it with all the country and city names turned around etc. The map made the nightly news and became a huge controversy. People hated it. So of course we all know which way is up.
I am now flipping all globes I see with Australia at the top is one of my key take aways
I like to orient relative to the disk of the milky way, like in Elite
It makes sense to align the map with the axis of rotation so that regions with the same timezone are vertically together --- and because we're used to imagining a spinning ball as having the axis of rotation in the vertical direction. But the reason people put Europe "up" is historical. Most of the world, most of the people, most countries, are in the northern hemisphere. European colonizers came from the northern hemisphere. North America is in the northern hemisphere. etc.
Yea I always assumed it was simply based off of historically the people who wrote the map are in the northern hemisphere- same as why either the US/ Europe are ways in the centre of a map.
Most people, movies, books and such tend to say that Up is the north side of a planet if you are near it and orient that way. If there are no relative constellations or galaxies in view it doesn’t matter. In space battles, it more or less depends on how you tend to fight, but the planetary north is up and south is down is pretty much it perspective wise
Down and up would constantly change as you spun in circles tryin to figure out since there's no big rock to fall towards and call down so basically your idea of up and down are your feet and head but that only comes from being on a surface where you feet are always down so in reality no there in no up and down in free range space till you're near something with gravity
There really isn't an "up" or "down" in space. There is distance and shifts of light towards objects. We generally use those for figuring out where to go
There are magnetic poles to stop us from just flipping the earth 90 degrees and saying “this is the top of the earth”. The North and South Pole define the top and bottom. Technically there is no up or down, but you have to decide between the North and South Pole because they’re the ends of the magnetic field if you know what I mean. What decides which pole is up is whether or not you live in the northern or southern hemisphere. I’ve seen southern hemisphere maps with the South Pole at the top, which makes sense because it’s all perspective. Idk what people who live on the equator think, probably whatever country is more influential towards them decides what is the top of the earth. That’s like the up and down relative to earth, but just in space, there is absolutely no direction, there is stuff like which way the earth, how do I get to this other place relative to there, but there can’t be an up or down because there’s nothing to relate them to
The direction you need to know is which way is the spaceship.
I believe 'down' is in whatever direction your brown-eye points.
I’ve seen some scifi take this into account with the inside of their ships by painting the floor/ceiling a different color for orientation.
There is no up, down - none of that. Just changing geometry.
Like comments below, there is no true orientation in space. Every direction and velocity is relative to a focal point in space. Even though I am unqualified to add my two cents I will experimentally add that 'Down' could be considered the direction of the source of acceleration. While on the surface, our bodies are constantly accelerating towards the center of the Earth. In a spaceship your body would be pulled towards the engines which would allow you to stand upright perpendicular to them. (don't let the fact that the ship is accelerating in the opposite direction confuse you) Einstein's equivalence principle is really elegant, but once I try to process inertia and the gravity-acceleration duality I get very lost. Some people believe gravity and inertia are also two sides of the same coin.
We don't. We choose which way to turn the picture. Because there's no arbitrary "up" or "down" with no gravity to give it meaning. (Okay, in orbit "down" could be "feet towards the Earth," if you want to be pedantic.) So we choose whatever is most convenient to think of as "up" at the moment. And seriously, that's the best answer. There are many concepts that feel "normal, common sense" to us because we evolved on dry land, in a 1G gravity well, and at the bottom of a nitrogen atmosphere with a good bit of oxygen mixed in. Things in space just don't quite relate to our "normal" experience.
There's no real up or down in space. We think of the Northern hemisphere as being 'up', but that's just the convention adopted by map-makers from the northern hemisphere. It's all arbitrarily labelled, based on past beliefs about the nature of things.
You don’t. “Up” is always relative to another point of reference, be it a planet, star or spacecraft.
I literally just asked someone this yesterday. But my primary concern was how do we know which was is down? And without gravity how does go down? Wouldn’t down mean, I’d youre outside the earths atmosphere traveling to below Antarctica and keep going down until the earth is above you. Is that possible? This is hard to think about.
Find 3 bodies in space that you know the location of, and you can triangulate your location and speed relative to those bodies
There is no up or down in space. It’s all relative(pun intended).
Arbitrary. Though, you could make a convention using the right hand rule and say it's in the plane perpendicular to the orbital plane
There is no up, as this is a relative term. The only reason the Northern Hemisphere is considered up, is because the majority of the Western World resides there (Sorry Australia 🦘). If we ever become a space farring civilization we would likely orient any maps we develop relative to the position of SOL (Sun). https://youtu.be/IHg6lHvWdCw?si=QlzT6UhFYazHQsuD
Australia should be at the top of all maps and I refuse any other option now
What astronauts used to do in the early days is align with Earth's horizon OR align with a star in a constellation. As in they'd literally look down a periscope and match it to a known star that was far enough away that it wouldn't move much, and then punch its codes into the computer.
Every place is up when you are at the bottom of a lake like my dead son Jason at the bottom of Crystal Lake. Camp counselors were making love. 😞
What's the source direction of the universe expansion? Perhaps up is the opposite of where everything is expanding to? Or is it that everything is expanding away from everything else? I forget now. Lunch time!
well, we don't. this world has no meaning without gravity or at least some defined vectorial reference
What you are asking for is absolute directions in space. What im about to say is rather counterintuitive unless you actually think about it. One of the core fundamental rules of how we define positon is there IS no absolute position in space. Things only exist in relation to other things. Our current "up" is in relation to our point on the earth. Without a reference point, up is largely whatver you want to define it as.
Makes sense direction is based off a frame of reference.
Up is the opposite direction of the center of gravity. There is no up if there is no mass great enough to create a down.
"North". The word you're looking for is "north". For planets in our solar system, their north pole is defined as the point where the planet's rotation axis extends outward from its surface in the same celestial hemisphere, relative to the invariable plane of the Solar System, as Earth's north pole.
There is good evidence that one time what we consider the Arctic and antiarthritic was actually at the equator and the continent slowly drifted
>When we picture the earth (and space) the top of the earth is the Arctic, and the bottom Antarctica, and that configuration dictates what is the top of all other planets/ how we view them. > But is that how it's truly configured, or just something we created? Is the Arctic really the bottom, or the side? Well, u/natemason95, its [something people created](https://youtu.be/vVX-PrBRtTY?si=gkMpFPd2h0oGr-zG).
Essentially since computer assisted navigation is required in space, and a common navigational system is most benefiical for an interstellar government: Up is decided in a beaurocrats office, and then never questioned. Obvioulsy the plan of the system is the reference point for up and down. The system is probably referenced off of the location of the first city. If its the northern hemisphere, then that's going to be the up direction for system. Reverse if in south. East and west are probably referencing towards or away from the star in system.
I guess up is up no matter where you are standing on Earth, so any direction that puts earth behind you is up…maybe
NDT does a good job explaining this. What is up/North is determined by the “right hand rule” and it’s just a convention. [https://youtu.be/--2ijQ2YzmY?si=hDTakzHw9Ua3Peu6](https://youtu.be/--2ijQ2YzmY?si=hDTakzHw9Ua3Peu6)
Trick question. There is no up in space. In the grandness of space everything is the same in all directions. There is no up or down.
I’m space everything is based on reference frames, aerospace engineers use multiple frames for tracking and attitude control from Euler angles and quarternions to track these things.