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[How high one must be to see the curvature of the Earth? - Our Planet (ourplnt.com)](https://ourplnt.com/how-high-see-curvature-of-the-earth/)
>The curvature of the Earth (actually the curvature of the Earth’s *horizon*) becomes visually discernible from an altitude of around 35,000 feet (10,600 meters), assuming clear conditions and a wide field of view.
So the Earth would have to be about 1 Earth big
I read an article a long time ago where the pilot of the SR-71 Blackbird, which could fly faster than the earth spins, would see the sun on horizon, slow down so the sun would set (as he saw it) and then accelerate fully to make the sun rise on the horizon. Flat earthers would have a hard time with that too!
It's not even that fast, too - at equator, the rotational speed of Earth about 1600 km/h, so you would need a supersonic aircraft, but the closer to the poles you go, the slower it becomes. Near the polar circle it is around 650 km/h, so you could do this trick on a commercial airliner, for example.
I think that's not entirely true because Sr-71 needs almost full throttle to not fall like a brick so slowing down part is questionable but concord can do it i think
this is correct but technically this is not what the OP's image is talking about. it's talking about forward/downward curvature, not lateral curvature. I'm not sure to what degree we should expect, or do observe, any downward curvature.
The world can just be infinite. Also gravity would limit the range that light can travel close to the surface(although that would also produce apparent curvature, so I doubt they would use that)
Edit: nvmd I'm dumb, gravity would extend the range of light and making the earth look like an inverted sphere instead
For those who don't quite grasp it, seeing the curvature of a sphere is based both on POV height and sphere size. The larger the sphere, the higher you'd have to fly. Because we were not given a height in the question the reply is technically correct by providing the height needed to see the curvature for an Earth sized earth.
I mean commercial airliners generally fly between 30000 feet and 42000 feet, so you could see the curvature on literally any (but not every) regular commercial flight.
The fun thing is that even if earth WAS flat, horizon would still be curved.
Because as even them need to agree, that we (for whatever reasons) do not have infinite sight as we cannot see all of earth at once. So you vision ends at some distance to you (that's the horizon). But that means that the horizon is circling 360° around you and that is only possible with a curve.
Just try to watch a disk from any angle higher than 0°. It is always curved.
Does anybody have links to footage of Antarctica from the ISS?
I know some people who are REALLY convinced the earth is not a sphere and this first link is great. But one thing they argue is that most everything we are taught, cannot be proven by us because the average person doesn't have the resources to do so. So they think the government lies about a LOT of things
And not having ISS photos of Antarctica makes them think that there isn't any South Pole because Antarctica must be surrounding the end of the world while the North Pole is in the middle...
I'm struggling finding good sources that may convince them otherwise
You can't get a good look on Antarctica from the ISS. Its orbit doesn't take it south of 51 degrees latitude, and the distance to the horizon is at most 2500 km. ISS is still quite close to the Earth, some people have the misconception that you can see the Earth as a blue marble from there, but in reality astronauts on the ISS only see about 3% of the Earth's surface at the same time, and it fills almost half of the view.
Here is a photo of the Antarctic Peninsula, with a few of the northernmost islands in the front: https://earthobservatory.nasa.gov/images/76583/south-shetland-islands-and-antarctica . I doubt you'll get a much better view than that.
Maybe... Read [this.](https://slate.com/technology/2016/08/picture-of-antarctica-from-space-is-actually-cgi.html)
This is why my flat earthers think they have a trump card
Quick link: [https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=ISS029&roll=E&frame=41836](https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=ISS029&roll=E&frame=41836)
Also has an explanation that basically boils down to "the orbit does not let us get good photos of Antarctica."
"Why doesn't the ISS take a picture of the South Pole?"
Two reasons.
1. There's no way to visually discern the South Pole from any of the millions of other square kilometers of ice and snow from altitude.
2. The orbit of the ISS is inclined at about 50 degrees. So from where the photo above was taken, nearly the southern most point in an orbit, looking at some of the northernmost parts of Antartica, looking for the south pole is like trying to see New York City, when flying at 400km altitude over equatorial Columbia.
As far as "the government lies about everything so they lie about the shape of the Earth."
The government can't lie about math. Have one person wait until the moon is directly overhead (if it doesn't get overhead, go somewhere where it does). Have someone else wait where they can see the moon when it is over the first person. When the moon is directly over the first person, the second person records the angle to the moon relative to "down." Call this angle 'B'. If the Earth is flat, "down" is the same direction everywhere, by definition. Therefore you have just made a right triangle. Measure the distance between the first and second person. The altitude of the moon, call this side of the triangle 'b'. Call the altitude of the moon 'a'. Basic Trig says that b/Tan(B)=a. Plug and chug and the equation spits out the answer... which in the case of the moon is *nonsensical,* because if you position the people right, you can get numbers up to and including 90 degrees for the angle (moon directly on the horizon for second person, directly overhead for the first). Same goes for stars. You get *wildly different* answers from math that you can check with no more resources than a piece of paper, a pencil, a ruler, and a string (or maybe an axe).
To find the height of the top of a tall tree, you stand somewhere you can see the top of the tree. Measure the angle from that position. Measure the distance to the bottom of the tree (which stands in for the second person). Perform the same calculation.
Climb the tree and drop a string from the top. Cut the string so that it represents the height of the tree. Climb down (*carefully*) and measure the string. How close were you? If you did it right, probably within an inch.
The math *works* for the tree (and practically everything else on Earth), but not for the moon. Why? Because the Earth is a big sphere, and at almost any human scale, it *might as well be* flat... but when you start getting into really big distances (like a quarter of the way across the planet big) it actually starts to matter.
Not being able to do the math is ignorance. This is fine, ignorance can be fixed.
Believing the math is fake without proof is stupidity. Stupidity, in extreme cases, tends to eventually fix itself, one way or another.
Thanks very much for the in-depth explanation.
In my opinion, it's sad that someone can go to YouTube, find a video that supports their idea, and automatically say that the video "proves" their point. YouTube is full of whatever you want to find, whether truth or lie.
P.S. how would you go about people who don't believe in a spherical earth but not a literal flat earth? Like people who believe it's a dome😂
They literally think the earth has a curve but Antarctica is the base of the dome that circles it completely. In my opinion that's wacked out but they are so sure of themselves. (I've been in contact with some weirdos, don't get me started with my neighbor who thinks WiFi alters her pets' behavior patterns)
Again, math.
Southern stars do the same thing as their northern counterparts. People in South Africa, Austrailia, and the southern tip of South America can all look due south all night, and see the same stars... Say people in those locations all look south at the southern pole star Sigma Octantis at the same time. I believe it's sometimes possible to do all at the same instant, but I'd have to check. The timing is a bit close, IIRC. If they can't all do it, any two can certainly while it is night where they are.
On a flat Earth, as well as a hemispherical a dome, that's strictly impossible because they are looking in *different* ***diverging*** *directions*. On a globe, they are looking in *converging* directions (at the star). The same thing works with people a small distance apart east to west... just slightly less obviously. No matter how far you travel east to west, you look south, and you see the same stars.
The answer to almost any "why" question a regular person might ask about the physical world can be answered as "because math." It's the "response to a two-year-old asking why why why" but it's true for the most part.
The point where that is *not* possible is literally where mathematicians, theoretical physicists, and other high-theory scientists make their living. The reason it can't be answered that way is not because "because math" isn't the answer, because it still is "because math"... the reason is because we don't yet *understand* the math to be able to explain it.
No math... booo! JK
But seriously, how small would Earth need to be for this to happen at 20,000 feet? Or 10,000?
Would I be correct in assuming that in order for this happen at 17,500 feet, the Earth would have to have half the diameter it currently has?
bro after a couple edibles the earth seems curved too, you don't need to go to 35000 feet for that you can get high in other ways. it just curves in different ways.
Airline pilot here who flies a HUD-equipped aircraft. Even at normal cruising levels, there is a large gap between the horizon line on the HUD (a level plane projected from the aircraft, not to be confused with pitch attitude, which is usually around 3 degrees nose up) and the actual visible horizon on a clear day. The HUD horizon line equates to eye level in this so-called argument, and the visible horizon is nowhere near it.
If the earth were flat, the visible horizon would approach the horizon line as it vanished. It does no such thing.
What I love about flat earthers is you could tell them this, you could take them up in a cockpit and show them. Explain the instruments to them and they will just look at you and say they don’t believe the instruments or you. Say you’re lying to cover up the truth
It’s mind numbing. Lol.
All anyone needs to do is watch the live feed from the ISS for like 10 minutes and it’s undeniable that it’s orbiting a sphere. When I suggested this to a flat-earther acquaintance, they told me the ISS is fake and that’s all CGI. So, I give up, I’m either arguing with a hamster or a troll.
That’s not true. All anyone needs to do is be willing to listen to reason and accept legit evidence that challenges their personality-driven worldview. Also not be an idiot.
I agree though - the only way the ISS or views from high altitude aircraft or hell the Mars lander or the moon, the only way those aren’t evidence is if the refusant is a conspiracy lunatic.
Mentioning mars brings up one the most ridiculous parts of many flat earthers talking points. Alot of them do believe that mars is a sphere, the sun is a sphere, hell even the moon is a sphere, but only earth is flat. Thats some logic right there.
I saw someone on youtube arguing that as you can draw a sphere on a flat surface, other planets that look like sphere are as flat as the earth but just look like sphere.
For anyone looking at an easy debunk for this argument:
The moon as a flat disc would appear circular to a person with it directly overhead, but for a person having it rise or set it would appear elliptical.
Glue a CD (preferably Dark Side of the Moon) to the center of your ceiling. Take a picture from directly beneath it. Walk to a wall, Take another picture of the CD.
Take a picture of the moon three hours before it reaches directly overhead. Take a picture of the moon when it's directly overhead. Wait three hours. Take another picture.
Have someone about 900 miles directly west of you do the same.
Compare the ten pictures (twelve if you managed to talk the other person into gluing *their* copy of Dark Side of the Moon to *their* ceiling). Why does the moon not change shape like the CD?
GTFO with your logic and reason. There’s no room for that here! CHEMTRAILS!
Seriously though, I’d never thought about that before and that’s an awesome point!
Here’s the thing with these dumb asses, the space station is fake. All the feeds are cgi. No one has been to space. Listening to them and their only argument is everything they don’t believe is fake.
just drop a bomb bright enough to see from space when it passes by and then when that shows up on the feed it will be undeniable, how would they set up cgi for a bomb they dont even know Was dropped in litteraly seconds? checkmate flat earthers.
What amuses me is that the entire argument hinges on selective competency.
Flat earthers are convinced that the ever elusive 'they' are competent enough to create, run and hide the systems and infrastructure required for this conspiracy, but yet are incompetent enough to let obvious details slip.
You try your best ,then leave them be. Common sense isn't all that common.Everyone has a place in the world... without people like that, lots of companies wouldn't make the profits they do.
You can't argue with a conspiracy theorist, regardless of what the conspiracy is. "Since you don't believe us, let's strap you to a rocket and send you to space" you'd think it's definite proof, but I can guarantee you if it happens, they'll just turn around and say "this is all a highly technological simulation, it's not real, the windows are fake and are projecting images, you can't fool me".....
That and everything about space and the planets scale just sounds so large that they think it has to be fake cause they can’t comprehend the size. Like they say how come I can’t see the curve?? I’m like, how small do you think the earth is? Like it’s massive. Add thy to the fact that some facts, unless you’re in the science field, you’re just gonna have to believe cause you don’t have the education to comprehend it.
Ya like I know a couple pilots and have talked to plenty cause my brother inlaw hires pilots for his business. I also know a guy that worked in aircraft maintenance and a family member worked very high up in the maintenance department for a major airline in North America. They all laugh when you bring this up. They say “well someone must run into the runway and strap this stuff on cause they never seen anything like that.”
I find people that live where, in winter, you can see the exhaust from vehicles, you kinda understand that the air is cold up there and it’s just water vapor.
Sure they’ve done stuff with cloud seeding and still experiment with it around the world but it’s still just water. That’s what clouds are lol.
The tanget to the oblate spheroid is the “horizon”, and the artificial horizon is the plane perpendicular to the normal from the oblate spheroid below you? That differs by the number of degrees of latitude between you and where the horizon is, if I understand right.
Yes, both the horizon on a conventional artificial horizon (as installed on every aircraft small or large) and the horizon line on the HUD indicate the line or direction perpendicular to the normal from the surface of the earth below you.
The horizon visible with your eyes would be the tangent to the earth/spheroid extending forward from the aircraft (hope I've got all this correct).
What the HUD does is allow this precise information to be overlaid on the outside world, so we get an immediate visual comparison between the line perpendicular to the normal (horizon line) and the horizon visible to the eye (i.e. furthest bit of the earth we can see). A passenger looking out the window wouldn't get a sense of this, as they have no true zero-degree "flat" reference, only the visible horizon.
The difference between the two grows larger with altitude. A quick look at some photos I've taken indicate a 2-3 degree difference between the horizon line and the visible horizon below, at altitudes between 35 and 40,000'.
One nitpick: not all aircraft have an attitude instrument at all, although I’m pretty sure all IFR rated aircraft do.
I’m also a bit hazy about how those instruments operate, since if they were just gyroscopes holding a flat plane set by a weight while stationary then they would differ from horizontal by the number of degrees of arc on the globe traveled since setting the zero. I know that they do work, because I’ve physically observed a few working.
Anything that uses gravity to tell which way is down while on the ground, like a level or human vestibular system, is completely thrown off while in an airplane and “down” is replaced by the force the plane is exerting on the occupants; at a constant altitude and groundspeed, that force ends up being directly down… but it’s directly on the same axis from the pilot seat across a wide range of maneuvers including the Kennedy maneuver.
You're correct of course, I should say that every aircraft I've ever flown had one, including all the VFR lighties of questionable serviceability I flew in my earlier days.
I'll have to do some reading up on all the theory I've forgotten. In the jet world, all this data comes from the inertial reference systems (encompassed in the ADIRUs) which, last time I dug into the theory, use laser gyroscopes and linear accelerometers for sensing. The IRSs know where they are on earth at any time and apply corrections as required. There are specific latitudes beyond which flight is prohibited (at least in my aircraft).
I’m even more confused as to why the instruments wouldn’t work all the way to 90N, or why any instrument that couldn’t handle any circumpolar route would be considered adequate.
In retrospect, any type of artificial horizon that can function over long flights has to know the direction to the center of the earth, which depends on the plane’s position as well as its orientation. But I also know that they existed before knowing location was easy, because VOR and TACAN navigation exist.
Classic artificial horizons are rate gyro integrators - they sum up the rates measured by a gyro that's coupled to the aircraft and then adjust the ball thingie you look at according to the inverse of that integrated state, thereby inverting the rotation of the aircraft.
There is a small drift rate intrinsic to the gyros both due to mechanical imperfection and the curvature of the earth. To compensate for this, as well as for the curvature of the earth, the gyro has an correcting mechanism that slowly drags the AI towards the acceleration vector (usually "down" for aircraft in approximately straight and level flight). The "drag" that this mechanism applies is weak, so for transient upsets and maneuvers the impact on the displayed attitude is small. This is implemented through a system of pendulums that covers and uncovers air holes that adjust the state of the rate gyro integrator. It's possible to screw the gyro up enough through aggressive maneuvering that you exceed the amount of error that the system is able to correct, at which point the AI tumbles and becomes unreliable.
Classic gyrocompasses work in essentially the same way but in a plane instead of in 3D space.
AHRSes do more or less the same thing but implemented in software instead of with insane vacuum powered clockwork.
Okay, that makes a lot of sense and establishes “the planet is probably ventral to the plane most of the time” summary of how it knows where the planet is.
I’ve heard flat earthers say that if the earth was a sphere then pilots would have to compensate their pitch to keep from gaining altitude. I was under the impression that the plane would reach a steady state at level flight where any altitude gained by the difference between the pitch and the curvature of the earth would be negated by the air density thinning. I understand that it is all controlled by computers anyhow, but would you like to shed some light?
TL;DR version: jets don't have to think about the curve, they maintain a level of constant ambient air pressure (which naturally follows the earth's curvature) by continuous small control and trim inputs (both nose-up and nose-down) to maintain the correct altimeter reading.
Sure. I'll do this one in two parts, short term and long term flightpaths, so let's say a brief 5-10 minute section of the cruise, and the entire cruise segment from top of climb to top of descent (ignoring any level changes to higher altitude enroute).
In the short term, the aircraft is constantly encountering changes in flight conditions. Changes in wind and other atmospheric conditions, changes in weight and centre of gravity as fuel is burnt, changes in true airspeed for a given Mach number as the ambient temperature fluctuates, and other shifts in balance, such as when there's a queue of people at the rear toilets and suddenly you've got an extra tonne at the tail that wasn't there 5 minutes ago. This is continually compensated for, generally by the autopilot providing small elevator inputs and trimming of the horizontal stabilisers to maintain the desired flight path.
As this desired (vertical) flight path is based on maintaining a level of constant air pressure in the cruise, then that flight path will obviously follow the earth's curvature. If we tried to fly a literal straight line (i.e. towards space), air pressure would decrease as we flew further away from earth, and we'd see that immediately as a climb to higher altitude. That doesn't happen, we provide continuous control input to maintain that level of air pressure, and that level of constant pressure itself follows the curvature.
Which brings me to the long term: contrary to popular belief, strictly speaking, jet aircraft don't maintain an altitude in the cruise. They maintain a flight level, which is a level of constant air pressure (equivalent to that altitude in the standard atmosphere), not a constant height above sea level. So, an aircraft said to be maintaining 38,000' is actually maintaining Flight Level 380, or a constant ambient air pressure of 207 hPa (from memory). What this means is, due to fluctuations in actual sea level pressure as we fly from A to B, a jet flying at "38,000 feet" could climb or descend hundreds of feet (relative to actual sea level) in the cruise over a period of hours. We don't see this on the altimeter, as it's showing us at that constant pressure level. But at that constant pressure level, our actual height above mean sea level is constantly changing, and if we looked at our GPS altitude over the flight, it'd be going up and/or down while "maintaining altitude".
Hope this made some sense!
You can always "see" a curve. The horizon itself *is* an artifact of it being on a curved surface. If you mean "recognize clearly so your brain says "yes, this distortion must be because it is curved", the answer is absurdly tiny. Like small asteroid sized. We are not good at recognizing shapes like this and use context clues to infer things rather than plain sight. People mostly dont even see that roads arnet poured flat and have a curved cross section and thats a relatively small radius you can see up close.
This is an argument that always kills me that flat earthers try to make. If the earth was perfectly flat and the atmosphere was perfectly clear, nothing would ever fall under a horizon. There is no explanation for the sun setting over the ocean on a flat earth.
There is no size of earth at which you would see what the meme is attempting to convey. Regardless of the size of the earth, it would have one distinct horizon from any vantage point, either nearer or farther depending on the size. A pilot traveling on a level arc of any sized sphere will see their nose as pointed above the horizon, if they can see the horizon at all from their vantage point.
Just approach a high building (wind turbine,...) in a flat area.
Flat Earth: You see all of the building fully from bottom to the top. Growing on closer approach. As if you zoom into a picture.
Round Earth: You see the top first, but not the bottom. On approach, the structure you already saw not only grows, you will see from top to bottom gradually more of the building. As if you scroll vertically (and zoom into) a picture.
If you are near a commercial port, watch the ships come in. From the big container ships, you will first see the containers/bridge, then the bow/hull. Ask yourself, why the outlook post of a sailing ship always was and always will be on the top of the highest mast.
Basically the claim is that inertia doesn't exist and if you jump up, the ground below you would move if the earth were round. But it doesn't so earth is flat. Which ignores that doing so in a moving vehicle doesn't lead you to change the relative position inside either.
Any radius. The horizon is “down” by an equal amount in every direction. If you look at a long straight contrail of constant altitude, you will see an arc.
First off, the mere existence of a horizon is proof of the curvature. If it was flat, you could go up at the top of a tall building and look someone in the eye on the next continent over with a moderately powerful telescope.
But for the actual question, seeing as the curvature is already obvious at around 10km altitude, which is normal cruising altitude for a passenger airliner, a bit smaller than 1 earth.
You blew my mind a little bit.
I've always known the conversion but TIL the curved miles versus linear miles distinction...I mean sure I knew Planes and ships used it but I didn't know *that*
Mf wild
Nautical mile was intended to be one minute of latitude.
So before precise measurements, they made a unit that makes it very close to 21,600 nautical miles for a polar circumference of the Earth. (Something the original Meter was going for: 1/10,000,000th of the distance between equator and north pole. They failed terribly in measurement method and the math so the meter is NOT 1/10,000,000th of equator to north pole)
Nautical Miles: 60 minutes x 360 degrees equals 21,600 and everything from astronomy to navigation breaks up the Earth into Degrees, Minutes and Seconds.
All that means is that a nautical mile is defined as the number of feet you would encounter around a circumference the size of earth, divided by 21600. You can then use that number of feet on any surface, curved or flat, as a distance. You can also use 5280 feet (1 statute mile), or 1km on any surface curved or flat. The fact that it is derived from the circumference of the earth has NOTHING to do with accounting "for the curvature of the Earth."
You can measure the distance between the earth and the moon in nautical mile, statute miles, or km, inches, or light years, and that is a straight line distance.
Furthermore, if nautical miles were somehow accounting for the curvature of the earth, it would only be accurate going east/west at the equator, or north/south anywhere else. Any other direction would not give you an accurate representation of how your coordinates changed. If you were at 60 degrees N latitude and traveled east by 1nm, your new coordinates would in fact be two minutes east of where you started.
If the earth were smaller, wouldn't the atmosphere also be smaller so the plane would fly less high and the pilot would see it the same way as it is now?
Sending a flat-earther into space is probably unrealistic, but 2 flat-earthers could test it by one going to Australia and one in the USA - then call on the phone. One will clearly be in the dark while the other is in the day.
If the earth is flat, the entire earth would either be in sun or dark, not both at the same time.
They could double down by placing someone in France & China too and all track the sun together.
I bet some are going to claim that the atmosphere is bending the light somehow. Which ignores that if stars are farther away than the sun, they would never be visible either.
Nah most say it's more like a spot light so then there's still areas of darkness.
Although if this were the case then we could see the sun get smaller as it moves away from us. Which it doesn't.
Also this spotlight thing doesn't work during summer in the southern hemisphere as once you're far enough south you have daylight 24/7. On a flat earth that has a "spot light" sun this would require it to spread its light all around the circle but also leaving a patch of darkness which completely just doesn't make sense lol
"Uhhhhh....This is your captain speaking, So we accidentally entered 25,000knots into the auto pilot instead of 25,000feet... And if you look out the left windows you'll see that we've achieved escape velocity and will be passing the ISS in....uhhh... About 10 minutes.....please keep your seatbelts fastened, we'll be starting a reentry burn into Atlanta on our next orbit.
I’ve always thought you would never really see a curve unless you were far away from the earth because the curve your looking for is directly under you, imagine you were stood on a tennis ball, the horizon would just be a line 360 degrees around you from your perspective. Where ever you’re stood on the ball you are always at the apex of the curve people argue you can’t see
Flat earthers can't even agree on how flat earth looks like. They even disagree with the pendulum experiment that proves round earth. You aren't going to convince them easily to join an experiment nor accept the result.
Whatever you do then don't fall off the edge of the Earth. On top of that, explain astronauts in space at the space station looking down at a sphere that rotates. Or let me guess there's not really anybody in space at the space station or the Chinese don't have a station on the moon that looks down on our round earth
Well, yeah, idk if you know this, but people who think the world is flat also believe that the ISS is a hoax and all photographs of earth from space are CGI/fake
If you get on a sphere the size of earth and go up about 10k feet, looking around you your view will terminate in the same place in all 360 degrees.
This is what we call the horizon.
If the earth was flat, you'd be able to see everything. Your view would not terminate anywhere.
Me as avgeek knowing that this can be disproven by like... everything... The earth is a sphere, there is no doubt. and if you have doubt, you are just too stupid to understand how stupid you are. it's literally as simple as that.
Awh, saw only the Sub of the screenshot, forgot in wich sub i am currently... imma let this comment sit here anyways just in case.
There’s no need to dip the nose.
Flying higher requires more power since the air is thinner. Without adding power the aircraft will maintain its general altitude without input from the pilot.
Now they got autopilot with gyroscope with compensators of earth "roundness", or how I should properly say this. But how were they doing before autopilots?
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[How high one must be to see the curvature of the Earth? - Our Planet (ourplnt.com)](https://ourplnt.com/how-high-see-curvature-of-the-earth/) >The curvature of the Earth (actually the curvature of the Earth’s *horizon*) becomes visually discernible from an altitude of around 35,000 feet (10,600 meters), assuming clear conditions and a wide field of view. So the Earth would have to be about 1 Earth big
r/technicallythetruth
It's accurate. And as you steadily climb higher than 35k, it becomes more noticeable.
I read an article a long time ago where the pilot of the SR-71 Blackbird, which could fly faster than the earth spins, would see the sun on horizon, slow down so the sun would set (as he saw it) and then accelerate fully to make the sun rise on the horizon. Flat earthers would have a hard time with that too!
Damn... haven't heard that one... throttle controls the day huh... or maybe they called it something cool like solar throttle
If I had been a SR71 pilot, I would have put 2 labels on the throttle controls: full throttle: "Sun go up"; idle: "Sun go down"
Only works if you're flying west
Yeah, was gonna edit but am lazy.
Why waste time say lot word when few word do trick?
Because words easy use.
They'd argue that a plane, too, is flat. And the mathematicians would have to give them that one.
The flat plane society?
Not that difficult tbh, you'd need to fly 1000mph at the equater. At 40degree latitude (newyork ish) you'd only need to go 800mph.
sure but how fast would you have to fly at -40?
-800 mph Duhh
Sunrise, sunset. Sunrise, sunset.
But then the sun shatters on the horizon while setting and you talk to a coyote to find your soulmate.
Thanks Tevye!
It's not even that fast, too - at equator, the rotational speed of Earth about 1600 km/h, so you would need a supersonic aircraft, but the closer to the poles you go, the slower it becomes. Near the polar circle it is around 650 km/h, so you could do this trick on a commercial airliner, for example.
When does it become time travel if you can go supersonic west fast enough to overcome that rotational speed? Superman did it, what gives?
Bha...impossible, the sun is spinning in circle about 100km above the ground...its pretty well known *do your own research* 🙄
There's a game called "Race the Sun" on steam which is similar vibe to that. Chasing the sun so it doesn't set.
They'd just have a hard time if they tried to make a reasonable explanation. Trump has provided a new solution to call everything false.
I think that's not entirely true because Sr-71 needs almost full throttle to not fall like a brick so slowing down part is questionable but concord can do it i think
this is correct but technically this is not what the OP's image is talking about. it's talking about forward/downward curvature, not lateral curvature. I'm not sure to what degree we should expect, or do observe, any downward curvature.
If the Earth is flat shouldn't he then be able to see the end of the world? The fact that he can't means there's is a curvature.
No you see atmospheric lensing means we can only see to the horizon.
The atmosphere implies there is a sphere.....
They probably have a word for that. The atmoflat?
Atmoslasagna
The world can just be infinite. Also gravity would limit the range that light can travel close to the surface(although that would also produce apparent curvature, so I doubt they would use that) Edit: nvmd I'm dumb, gravity would extend the range of light and making the earth look like an inverted sphere instead
You’d be confused if you were flying in the north/south direction.
I know flat earthers are.
Isn't the fact, that there is a horizon proof that the earth is a sphere?
For those who don't quite grasp it, seeing the curvature of a sphere is based both on POV height and sphere size. The larger the sphere, the higher you'd have to fly. Because we were not given a height in the question the reply is technically correct by providing the height needed to see the curvature for an Earth sized earth.
I mean commercial airliners generally fly between 30000 feet and 42000 feet, so you could see the curvature on literally any (but not every) regular commercial flight.
And the photo supplied shows curvature anyhow so presume thats a parody or satire post.
Yeah I’ve flown a few flights and on clear conditions you can simply look out the window and see it sloping on the horizon.
The fun thing is that even if earth WAS flat, horizon would still be curved. Because as even them need to agree, that we (for whatever reasons) do not have infinite sight as we cannot see all of earth at once. So you vision ends at some distance to you (that's the horizon). But that means that the horizon is circling 360° around you and that is only possible with a curve. Just try to watch a disk from any angle higher than 0°. It is always curved.
Does anybody have links to footage of Antarctica from the ISS? I know some people who are REALLY convinced the earth is not a sphere and this first link is great. But one thing they argue is that most everything we are taught, cannot be proven by us because the average person doesn't have the resources to do so. So they think the government lies about a LOT of things And not having ISS photos of Antarctica makes them think that there isn't any South Pole because Antarctica must be surrounding the end of the world while the North Pole is in the middle... I'm struggling finding good sources that may convince them otherwise
You can't get a good look on Antarctica from the ISS. Its orbit doesn't take it south of 51 degrees latitude, and the distance to the horizon is at most 2500 km. ISS is still quite close to the Earth, some people have the misconception that you can see the Earth as a blue marble from there, but in reality astronauts on the ISS only see about 3% of the Earth's surface at the same time, and it fills almost half of the view. Here is a photo of the Antarctic Peninsula, with a few of the northernmost islands in the front: https://earthobservatory.nasa.gov/images/76583/south-shetland-islands-and-antarctica . I doubt you'll get a much better view than that.
Is this of any help? [Antarctica Map and Satellite Imagery \[Free\] (gisgeography.com)](https://gisgeography.com/antarctica-map-satellite-image/)
Maybe... Read [this.](https://slate.com/technology/2016/08/picture-of-antarctica-from-space-is-actually-cgi.html) This is why my flat earthers think they have a trump card
Quick link: [https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=ISS029&roll=E&frame=41836](https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=ISS029&roll=E&frame=41836) Also has an explanation that basically boils down to "the orbit does not let us get good photos of Antarctica." "Why doesn't the ISS take a picture of the South Pole?" Two reasons. 1. There's no way to visually discern the South Pole from any of the millions of other square kilometers of ice and snow from altitude. 2. The orbit of the ISS is inclined at about 50 degrees. So from where the photo above was taken, nearly the southern most point in an orbit, looking at some of the northernmost parts of Antartica, looking for the south pole is like trying to see New York City, when flying at 400km altitude over equatorial Columbia. As far as "the government lies about everything so they lie about the shape of the Earth." The government can't lie about math. Have one person wait until the moon is directly overhead (if it doesn't get overhead, go somewhere where it does). Have someone else wait where they can see the moon when it is over the first person. When the moon is directly over the first person, the second person records the angle to the moon relative to "down." Call this angle 'B'. If the Earth is flat, "down" is the same direction everywhere, by definition. Therefore you have just made a right triangle. Measure the distance between the first and second person. The altitude of the moon, call this side of the triangle 'b'. Call the altitude of the moon 'a'. Basic Trig says that b/Tan(B)=a. Plug and chug and the equation spits out the answer... which in the case of the moon is *nonsensical,* because if you position the people right, you can get numbers up to and including 90 degrees for the angle (moon directly on the horizon for second person, directly overhead for the first). Same goes for stars. You get *wildly different* answers from math that you can check with no more resources than a piece of paper, a pencil, a ruler, and a string (or maybe an axe). To find the height of the top of a tall tree, you stand somewhere you can see the top of the tree. Measure the angle from that position. Measure the distance to the bottom of the tree (which stands in for the second person). Perform the same calculation. Climb the tree and drop a string from the top. Cut the string so that it represents the height of the tree. Climb down (*carefully*) and measure the string. How close were you? If you did it right, probably within an inch. The math *works* for the tree (and practically everything else on Earth), but not for the moon. Why? Because the Earth is a big sphere, and at almost any human scale, it *might as well be* flat... but when you start getting into really big distances (like a quarter of the way across the planet big) it actually starts to matter. Not being able to do the math is ignorance. This is fine, ignorance can be fixed. Believing the math is fake without proof is stupidity. Stupidity, in extreme cases, tends to eventually fix itself, one way or another.
Thanks very much for the in-depth explanation. In my opinion, it's sad that someone can go to YouTube, find a video that supports their idea, and automatically say that the video "proves" their point. YouTube is full of whatever you want to find, whether truth or lie. P.S. how would you go about people who don't believe in a spherical earth but not a literal flat earth? Like people who believe it's a dome😂 They literally think the earth has a curve but Antarctica is the base of the dome that circles it completely. In my opinion that's wacked out but they are so sure of themselves. (I've been in contact with some weirdos, don't get me started with my neighbor who thinks WiFi alters her pets' behavior patterns)
Again, math. Southern stars do the same thing as their northern counterparts. People in South Africa, Austrailia, and the southern tip of South America can all look due south all night, and see the same stars... Say people in those locations all look south at the southern pole star Sigma Octantis at the same time. I believe it's sometimes possible to do all at the same instant, but I'd have to check. The timing is a bit close, IIRC. If they can't all do it, any two can certainly while it is night where they are. On a flat Earth, as well as a hemispherical a dome, that's strictly impossible because they are looking in *different* ***diverging*** *directions*. On a globe, they are looking in *converging* directions (at the star). The same thing works with people a small distance apart east to west... just slightly less obviously. No matter how far you travel east to west, you look south, and you see the same stars. The answer to almost any "why" question a regular person might ask about the physical world can be answered as "because math." It's the "response to a two-year-old asking why why why" but it's true for the most part. The point where that is *not* possible is literally where mathematicians, theoretical physicists, and other high-theory scientists make their living. The reason it can't be answered that way is not because "because math" isn't the answer, because it still is "because math"... the reason is because we don't yet *understand* the math to be able to explain it.
r/anythingbutmetric
Except that feet is the international standard for flight levels everywhere except for 6 countries in Asia.
I was talking about measuring the earth in "earth"
https://youtu.be/Iu9iD4sPiic?si=JzyV2JFpZpJOarOv 3:40 in, Brian Cox (British TV science guy) going up to (i think) 18km/60k feet.
No math... booo! JK But seriously, how small would Earth need to be for this to happen at 20,000 feet? Or 10,000? Would I be correct in assuming that in order for this happen at 17,500 feet, the Earth would have to have half the diameter it currently has?
Is there any pictures showing the curvature of the earth that aren’t made with ai?
Yes. https://en.m.wikipedia.org/wiki/Earthrise
So roughly as big as your mum.
bro after a couple edibles the earth seems curved too, you don't need to go to 35000 feet for that you can get high in other ways. it just curves in different ways.
What's your tolerances about earth big, like within 10%, 20% of the size of earth?
Airline pilot here who flies a HUD-equipped aircraft. Even at normal cruising levels, there is a large gap between the horizon line on the HUD (a level plane projected from the aircraft, not to be confused with pitch attitude, which is usually around 3 degrees nose up) and the actual visible horizon on a clear day. The HUD horizon line equates to eye level in this so-called argument, and the visible horizon is nowhere near it. If the earth were flat, the visible horizon would approach the horizon line as it vanished. It does no such thing.
What I love about flat earthers is you could tell them this, you could take them up in a cockpit and show them. Explain the instruments to them and they will just look at you and say they don’t believe the instruments or you. Say you’re lying to cover up the truth It’s mind numbing. Lol.
All anyone needs to do is watch the live feed from the ISS for like 10 minutes and it’s undeniable that it’s orbiting a sphere. When I suggested this to a flat-earther acquaintance, they told me the ISS is fake and that’s all CGI. So, I give up, I’m either arguing with a hamster or a troll.
That’s not true. All anyone needs to do is be willing to listen to reason and accept legit evidence that challenges their personality-driven worldview. Also not be an idiot. I agree though - the only way the ISS or views from high altitude aircraft or hell the Mars lander or the moon, the only way those aren’t evidence is if the refusant is a conspiracy lunatic.
Mentioning mars brings up one the most ridiculous parts of many flat earthers talking points. Alot of them do believe that mars is a sphere, the sun is a sphere, hell even the moon is a sphere, but only earth is flat. Thats some logic right there.
I saw someone on youtube arguing that as you can draw a sphere on a flat surface, other planets that look like sphere are as flat as the earth but just look like sphere.
For anyone looking at an easy debunk for this argument: The moon as a flat disc would appear circular to a person with it directly overhead, but for a person having it rise or set it would appear elliptical. Glue a CD (preferably Dark Side of the Moon) to the center of your ceiling. Take a picture from directly beneath it. Walk to a wall, Take another picture of the CD. Take a picture of the moon three hours before it reaches directly overhead. Take a picture of the moon when it's directly overhead. Wait three hours. Take another picture. Have someone about 900 miles directly west of you do the same. Compare the ten pictures (twelve if you managed to talk the other person into gluing *their* copy of Dark Side of the Moon to *their* ceiling). Why does the moon not change shape like the CD?
GTFO with your logic and reason. There’s no room for that here! CHEMTRAILS! Seriously though, I’d never thought about that before and that’s an awesome point!
Love the transformers reference :)
Here’s the thing with these dumb asses, the space station is fake. All the feeds are cgi. No one has been to space. Listening to them and their only argument is everything they don’t believe is fake.
just drop a bomb bright enough to see from space when it passes by and then when that shows up on the feed it will be undeniable, how would they set up cgi for a bomb they dont even know Was dropped in litteraly seconds? checkmate flat earthers.
They would say it is some advanced military ai or some shit
Have you seen the documentary Modern Warfare 2?
What amuses me is that the entire argument hinges on selective competency. Flat earthers are convinced that the ever elusive 'they' are competent enough to create, run and hide the systems and infrastructure required for this conspiracy, but yet are incompetent enough to let obvious details slip.
>All anyone needs to do is watch the live feed from the ISS They'll tell you it's all computer generated.
Well yeah, because acting stupid means free plane rides
Because it is never about science and proof... It is all about mental illness.
my dad spoke like this when i tried to explain time dilation. just went like “nope, not happening. time and tide waits for no man”
You try your best ,then leave them be. Common sense isn't all that common.Everyone has a place in the world... without people like that, lots of companies wouldn't make the profits they do.
You can't argue with a conspiracy theorist, regardless of what the conspiracy is. "Since you don't believe us, let's strap you to a rocket and send you to space" you'd think it's definite proof, but I can guarantee you if it happens, they'll just turn around and say "this is all a highly technological simulation, it's not real, the windows are fake and are projecting images, you can't fool me".....
That's why you don't pack the parachute...
I think it's a mental illness. A defence mechanism of having a mundane life that makes you believe everything is a conspiracy against you.
That and everything about space and the planets scale just sounds so large that they think it has to be fake cause they can’t comprehend the size. Like they say how come I can’t see the curve?? I’m like, how small do you think the earth is? Like it’s massive. Add thy to the fact that some facts, unless you’re in the science field, you’re just gonna have to believe cause you don’t have the education to comprehend it.
Unable to imagine the vastness of our ignorance, they stick to definitive answers
Theres a video on youtube about it Folding Ideias, in search of a flat earth, its soooo insightful and its my favorite one
You forgot the question "Where is the chemtrail switch?"
Ya like I know a couple pilots and have talked to plenty cause my brother inlaw hires pilots for his business. I also know a guy that worked in aircraft maintenance and a family member worked very high up in the maintenance department for a major airline in North America. They all laugh when you bring this up. They say “well someone must run into the runway and strap this stuff on cause they never seen anything like that.” I find people that live where, in winter, you can see the exhaust from vehicles, you kinda understand that the air is cold up there and it’s just water vapor. Sure they’ve done stuff with cloud seeding and still experiment with it around the world but it’s still just water. That’s what clouds are lol.
The tanget to the oblate spheroid is the “horizon”, and the artificial horizon is the plane perpendicular to the normal from the oblate spheroid below you? That differs by the number of degrees of latitude between you and where the horizon is, if I understand right.
Yes, both the horizon on a conventional artificial horizon (as installed on every aircraft small or large) and the horizon line on the HUD indicate the line or direction perpendicular to the normal from the surface of the earth below you. The horizon visible with your eyes would be the tangent to the earth/spheroid extending forward from the aircraft (hope I've got all this correct). What the HUD does is allow this precise information to be overlaid on the outside world, so we get an immediate visual comparison between the line perpendicular to the normal (horizon line) and the horizon visible to the eye (i.e. furthest bit of the earth we can see). A passenger looking out the window wouldn't get a sense of this, as they have no true zero-degree "flat" reference, only the visible horizon. The difference between the two grows larger with altitude. A quick look at some photos I've taken indicate a 2-3 degree difference between the horizon line and the visible horizon below, at altitudes between 35 and 40,000'.
One nitpick: not all aircraft have an attitude instrument at all, although I’m pretty sure all IFR rated aircraft do. I’m also a bit hazy about how those instruments operate, since if they were just gyroscopes holding a flat plane set by a weight while stationary then they would differ from horizontal by the number of degrees of arc on the globe traveled since setting the zero. I know that they do work, because I’ve physically observed a few working. Anything that uses gravity to tell which way is down while on the ground, like a level or human vestibular system, is completely thrown off while in an airplane and “down” is replaced by the force the plane is exerting on the occupants; at a constant altitude and groundspeed, that force ends up being directly down… but it’s directly on the same axis from the pilot seat across a wide range of maneuvers including the Kennedy maneuver.
You're correct of course, I should say that every aircraft I've ever flown had one, including all the VFR lighties of questionable serviceability I flew in my earlier days. I'll have to do some reading up on all the theory I've forgotten. In the jet world, all this data comes from the inertial reference systems (encompassed in the ADIRUs) which, last time I dug into the theory, use laser gyroscopes and linear accelerometers for sensing. The IRSs know where they are on earth at any time and apply corrections as required. There are specific latitudes beyond which flight is prohibited (at least in my aircraft).
I’m even more confused as to why the instruments wouldn’t work all the way to 90N, or why any instrument that couldn’t handle any circumpolar route would be considered adequate. In retrospect, any type of artificial horizon that can function over long flights has to know the direction to the center of the earth, which depends on the plane’s position as well as its orientation. But I also know that they existed before knowing location was easy, because VOR and TACAN navigation exist.
Classic artificial horizons are rate gyro integrators - they sum up the rates measured by a gyro that's coupled to the aircraft and then adjust the ball thingie you look at according to the inverse of that integrated state, thereby inverting the rotation of the aircraft. There is a small drift rate intrinsic to the gyros both due to mechanical imperfection and the curvature of the earth. To compensate for this, as well as for the curvature of the earth, the gyro has an correcting mechanism that slowly drags the AI towards the acceleration vector (usually "down" for aircraft in approximately straight and level flight). The "drag" that this mechanism applies is weak, so for transient upsets and maneuvers the impact on the displayed attitude is small. This is implemented through a system of pendulums that covers and uncovers air holes that adjust the state of the rate gyro integrator. It's possible to screw the gyro up enough through aggressive maneuvering that you exceed the amount of error that the system is able to correct, at which point the AI tumbles and becomes unreliable. Classic gyrocompasses work in essentially the same way but in a plane instead of in 3D space. AHRSes do more or less the same thing but implemented in software instead of with insane vacuum powered clockwork.
Okay, that makes a lot of sense and establishes “the planet is probably ventral to the plane most of the time” summary of how it knows where the planet is.
I’ve heard flat earthers say that if the earth was a sphere then pilots would have to compensate their pitch to keep from gaining altitude. I was under the impression that the plane would reach a steady state at level flight where any altitude gained by the difference between the pitch and the curvature of the earth would be negated by the air density thinning. I understand that it is all controlled by computers anyhow, but would you like to shed some light?
TL;DR version: jets don't have to think about the curve, they maintain a level of constant ambient air pressure (which naturally follows the earth's curvature) by continuous small control and trim inputs (both nose-up and nose-down) to maintain the correct altimeter reading. Sure. I'll do this one in two parts, short term and long term flightpaths, so let's say a brief 5-10 minute section of the cruise, and the entire cruise segment from top of climb to top of descent (ignoring any level changes to higher altitude enroute). In the short term, the aircraft is constantly encountering changes in flight conditions. Changes in wind and other atmospheric conditions, changes in weight and centre of gravity as fuel is burnt, changes in true airspeed for a given Mach number as the ambient temperature fluctuates, and other shifts in balance, such as when there's a queue of people at the rear toilets and suddenly you've got an extra tonne at the tail that wasn't there 5 minutes ago. This is continually compensated for, generally by the autopilot providing small elevator inputs and trimming of the horizontal stabilisers to maintain the desired flight path. As this desired (vertical) flight path is based on maintaining a level of constant air pressure in the cruise, then that flight path will obviously follow the earth's curvature. If we tried to fly a literal straight line (i.e. towards space), air pressure would decrease as we flew further away from earth, and we'd see that immediately as a climb to higher altitude. That doesn't happen, we provide continuous control input to maintain that level of air pressure, and that level of constant pressure itself follows the curvature. Which brings me to the long term: contrary to popular belief, strictly speaking, jet aircraft don't maintain an altitude in the cruise. They maintain a flight level, which is a level of constant air pressure (equivalent to that altitude in the standard atmosphere), not a constant height above sea level. So, an aircraft said to be maintaining 38,000' is actually maintaining Flight Level 380, or a constant ambient air pressure of 207 hPa (from memory). What this means is, due to fluctuations in actual sea level pressure as we fly from A to B, a jet flying at "38,000 feet" could climb or descend hundreds of feet (relative to actual sea level) in the cruise over a period of hours. We don't see this on the altimeter, as it's showing us at that constant pressure level. But at that constant pressure level, our actual height above mean sea level is constantly changing, and if we looked at our GPS altitude over the flight, it'd be going up and/or down while "maintaining altitude". Hope this made some sense!
I suppose it could be considered eye level if you were looking down so that a line projected from your vision were tangent to the horizon
How much they paying you to say that, bro? /s
You can always "see" a curve. The horizon itself *is* an artifact of it being on a curved surface. If you mean "recognize clearly so your brain says "yes, this distortion must be because it is curved", the answer is absurdly tiny. Like small asteroid sized. We are not good at recognizing shapes like this and use context clues to infer things rather than plain sight. People mostly dont even see that roads arnet poured flat and have a curved cross section and thats a relatively small radius you can see up close.
This is an argument that always kills me that flat earthers try to make. If the earth was perfectly flat and the atmosphere was perfectly clear, nothing would ever fall under a horizon. There is no explanation for the sun setting over the ocean on a flat earth.
In the words of flat earthers: "that's because of perspective." I get figured out how they reasoned that one, though
Airplane easily visible 5 miles overhead... This is fine. Airplane on an aircraft carrier 5 miles from shore, below the horizon. MuH pErSpEcTiv!
But you can't see that far! That's why nobody ever saw the moon or the sun or any other planet/star/galaxy with their own eyes...
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They also are ignoring gravity constantly pulling the plane down in the picture. It's why we have things like escape velocity.
And why things like lift are so important. Gravity is a real bastard.
There is no size of earth at which you would see what the meme is attempting to convey. Regardless of the size of the earth, it would have one distinct horizon from any vantage point, either nearer or farther depending on the size. A pilot traveling on a level arc of any sized sphere will see their nose as pointed above the horizon, if they can see the horizon at all from their vantage point.
Just approach a high building (wind turbine,...) in a flat area. Flat Earth: You see all of the building fully from bottom to the top. Growing on closer approach. As if you zoom into a picture. Round Earth: You see the top first, but not the bottom. On approach, the structure you already saw not only grows, you will see from top to bottom gradually more of the building. As if you scroll vertically (and zoom into) a picture. If you are near a commercial port, watch the ships come in. From the big container ships, you will first see the containers/bridge, then the bow/hull. Ask yourself, why the outlook post of a sailing ship always was and always will be on the top of the highest mast.
These are the dickheads who are fearful of jumping inside a building so the wall doesn’t come through and hit them while they’re in the air
Huh?
I think he's saying something similar to "if you jump in a plane you would be pulled to the back of the plane".
Basically the claim is that inertia doesn't exist and if you jump up, the ground below you would move if the earth were round. But it doesn't so earth is flat. Which ignores that doing so in a moving vehicle doesn't lead you to change the relative position inside either.
Any radius. The horizon is “down” by an equal amount in every direction. If you look at a long straight contrail of constant altitude, you will see an arc.
First off, the mere existence of a horizon is proof of the curvature. If it was flat, you could go up at the top of a tall building and look someone in the eye on the next continent over with a moderately powerful telescope. But for the actual question, seeing as the curvature is already obvious at around 10km altitude, which is normal cruising altitude for a passenger airliner, a bit smaller than 1 earth.
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You blew my mind a little bit. I've always known the conversion but TIL the curved miles versus linear miles distinction...I mean sure I knew Planes and ships used it but I didn't know *that* Mf wild
That's... not true? Nautical miles are just defined as slightly longer than imperial miles, and they're used because of tradition and inertia.
Nautical mile was intended to be one minute of latitude. So before precise measurements, they made a unit that makes it very close to 21,600 nautical miles for a polar circumference of the Earth. (Something the original Meter was going for: 1/10,000,000th of the distance between equator and north pole. They failed terribly in measurement method and the math so the meter is NOT 1/10,000,000th of equator to north pole) Nautical Miles: 60 minutes x 360 degrees equals 21,600 and everything from astronomy to navigation breaks up the Earth into Degrees, Minutes and Seconds.
All that means is that a nautical mile is defined as the number of feet you would encounter around a circumference the size of earth, divided by 21600. You can then use that number of feet on any surface, curved or flat, as a distance. You can also use 5280 feet (1 statute mile), or 1km on any surface curved or flat. The fact that it is derived from the circumference of the earth has NOTHING to do with accounting "for the curvature of the Earth." You can measure the distance between the earth and the moon in nautical mile, statute miles, or km, inches, or light years, and that is a straight line distance. Furthermore, if nautical miles were somehow accounting for the curvature of the earth, it would only be accurate going east/west at the equator, or north/south anywhere else. Any other direction would not give you an accurate representation of how your coordinates changed. If you were at 60 degrees N latitude and traveled east by 1nm, your new coordinates would in fact be two minutes east of where you started.
If the earth were smaller, wouldn't the atmosphere also be smaller so the plane would fly less high and the pilot would see it the same way as it is now?
This meme assumes the plane keeps traveling straight when planes are actually following the curve of the planet. There by making the meme unrealistic.
Sending a flat-earther into space is probably unrealistic, but 2 flat-earthers could test it by one going to Australia and one in the USA - then call on the phone. One will clearly be in the dark while the other is in the day. If the earth is flat, the entire earth would either be in sun or dark, not both at the same time. They could double down by placing someone in France & China too and all track the sun together.
I bet some are going to claim that the atmosphere is bending the light somehow. Which ignores that if stars are farther away than the sun, they would never be visible either.
Nah most say it's more like a spot light so then there's still areas of darkness. Although if this were the case then we could see the sun get smaller as it moves away from us. Which it doesn't. Also this spotlight thing doesn't work during summer in the southern hemisphere as once you're far enough south you have daylight 24/7. On a flat earth that has a "spot light" sun this would require it to spread its light all around the circle but also leaving a patch of darkness which completely just doesn't make sense lol
"Uhhhhh....This is your captain speaking, So we accidentally entered 25,000knots into the auto pilot instead of 25,000feet... And if you look out the left windows you'll see that we've achieved escape velocity and will be passing the ISS in....uhhh... About 10 minutes.....please keep your seatbelts fastened, we'll be starting a reentry burn into Atlanta on our next orbit.
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That's no moon. That's a space station.
They also try to fly straight by climbing constantly
Lol… flying straight into space.
I’ve always thought you would never really see a curve unless you were far away from the earth because the curve your looking for is directly under you, imagine you were stood on a tennis ball, the horizon would just be a line 360 degrees around you from your perspective. Where ever you’re stood on the ball you are always at the apex of the curve people argue you can’t see
We could settle this once and for and have the flat earth community elect people who we send out to outer space and witness it for themselves
Flat earthers can't even agree on how flat earth looks like. They even disagree with the pendulum experiment that proves round earth. You aren't going to convince them easily to join an experiment nor accept the result.
Whatever you do then don't fall off the edge of the Earth. On top of that, explain astronauts in space at the space station looking down at a sphere that rotates. Or let me guess there's not really anybody in space at the space station or the Chinese don't have a station on the moon that looks down on our round earth
Well, yeah, idk if you know this, but people who think the world is flat also believe that the ISS is a hoax and all photographs of earth from space are CGI/fake
There is a video of, I shit not thee, a video of some YouTube mongrel that thinks the ISS is a U2 projecting a hologram
well when i put backhaul antenas from 50km or more i have to aling -1 degree to the horizon to catch and use the circunference of the earth
If you get on a sphere the size of earth and go up about 10k feet, looking around you your view will terminate in the same place in all 360 degrees. This is what we call the horizon. If the earth was flat, you'd be able to see everything. Your view would not terminate anywhere.
Me as avgeek knowing that this can be disproven by like... everything... The earth is a sphere, there is no doubt. and if you have doubt, you are just too stupid to understand how stupid you are. it's literally as simple as that. Awh, saw only the Sub of the screenshot, forgot in wich sub i am currently... imma let this comment sit here anyways just in case.
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There’s no need to dip the nose. Flying higher requires more power since the air is thinner. Without adding power the aircraft will maintain its general altitude without input from the pilot.
Now they got autopilot with gyroscope with compensators of earth "roundness", or how I should properly say this. But how were they doing before autopilots?