TARINunit9 Posted January 7, 2020 Share Posted January 7, 2020 Is it possible using geometry to estimate how high Earth Proxima missions are above Earth's surface? Whenever I have a moment to look around I start thinking "wow, these massive asteroids the size of houses don't look to be orbiting much higher than the real life International Space Station" Link to comment Share on other sites More sharing options...
(PSN)AyinDygra Posted January 7, 2020 Share Posted January 7, 2020 They're also the wreckage of an Orokin Tower, so tech could still be actively suspending it against all known physics. Just a thought. Link to comment Share on other sites More sharing options...
Sapphirya Posted January 7, 2020 Share Posted January 7, 2020 Actually some of the larger asteroids have rockets bolted to their undersides, so it looks like the Grineer might be actively maintaining their orbits. Probably for mining efforts and stuff. It's also possible that they have other craft (Ogmas and Dargyns?) that act as 'tugboats' to keep 'em aloft if they're not large or stable enough to mount thruster assemblies on. Link to comment Share on other sites More sharing options...
Firetempest Posted January 7, 2020 Share Posted January 7, 2020 You'd have to use the curvature of the horizon and arc degrees and whatnot. The surface is blown up aerial photography. Link to comment Share on other sites More sharing options...
CriticalFumble Posted January 7, 2020 Share Posted January 7, 2020 In short yes, there is a way. I believe the method would be to use the (linear) length from one end of the planet to the other as a given. Then find the angle centered on you, from one end of the plant's length to the other. With that you have three angles and a side of a triage - with which you can find the other two sides using trigonometry, and distance from the surface with another calculation. Spoilers, though, I believe the answer is "too close". The game (not the only offender on this thing) uses art and not physics - and as such they'll ignore scale rules to make everything look more clear, for plot or atmosphere reasons, or just for cool factor. Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 4 minutes ago, CriticalFumble said: I believe the method would be to use the (linear) length from one end of the planet to the other as a given. From horizon to horizon, or from pole to pole? Link to comment Share on other sites More sharing options...
32768 Posted January 7, 2020 Share Posted January 7, 2020 Earth's equator length is approximately 40k kilometers, IIRC. From that you can reverse Earth's radius (and diameter). Your warframe is about 2 meters tall, i think (might be wrong). So looking at Earth and comparing it to your warframe you can estimate its observable radius/diameter. Then you need to somehow un-transform perspective. I'm not sure how much smaller objects become when they are getting farther from the observer, but at least you could use another warframe for a reference and i think it would be safe to extrapolate. You could ask someone to move 100 meters away from you, assuming you see that warframe became 1 meter tall (compare to your warframe) at distance 100 meters, then every 100 meters halves observable dimensions. Or so i think. Double-check that at distance 200 meters you're seeing taht warframe is 0.5 meters tall. Knowing this factor, factual Earth radius and observable Earth radius, you could establish how far away Earth is from you. If perspective is not linear, then this will be more complicated, but i don't think that non-linear perspective is a thing, although i'm not really into optics. If you need actual numbers - check NASA site (don't check Wikipedia), i'm getting these numbers from the top of my head, they might not be correct. Link to comment Share on other sites More sharing options...
CriticalFumble Posted January 7, 2020 Share Posted January 7, 2020 58 minutes ago, TARINunit9 said: From horizon to horizon, or from pole to pole? Depends on what you can see. If both poles are visible from the railjack, that would probably be the best, but any correct number you can get should do for an estimation - the Earth is a sphere squished by its own rotation, so there's going to be inaccuracies if you don't have the right angle. - - - I actually did a quick search for the number: 7,916 mi / 12,756 km at the equator; 7899.86 mi / 12713.6 km pole-to-pole. Worth noting that you'll need to subtract the radius from the distance to earth calculation you do, otherwise you'll have a NASA Mars rover incident. Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 Follow-up question: Is it possible to estimate distance from an object of known diameter (altitude above Earth) by measuring how much it takes up in your field of view? In other words, if Point A is directly below my Archwing on Earth, and Point B is my Archwing, and Point C is on the horizon, can we use the angle ABC to measure altitude? Or are there too many trigonomic unknowns even with a known (averaged) radius of Earth? Link to comment Share on other sites More sharing options...
GrimSinner Posted January 7, 2020 Share Posted January 7, 2020 2 hours ago, TARINunit9 said: Is it possible using geometry to estimate how high Earth Proxima missions are above Earth's surface? Answer: Yes Next question. How high are Earth Proxima missions above Earth's surface? Answer: ________ km Because I need to know now but too lazy to do math. Link to comment Share on other sites More sharing options...
Chewarette Posted January 7, 2020 Share Posted January 7, 2020 (edited) Honestly seems like a bit higher than ISS but not much Edited January 7, 2020 by Chewarette Link to comment Share on other sites More sharing options...
Aekhon Posted January 7, 2020 Share Posted January 7, 2020 There are a couple of ways you could go about doing this, and my guess is that you're going to get different answers depending on which method you use because DE probably didn't bother to make things accurate. For instance, knowing that the Earth curves 360 degrees (sorry flat Earthers, Warframe's Earth is undeniably round), its diameter and your screen's FOV, you could calculate the amount of the Earth's curve you can fit in your screen, and then use the curvature formula to calculate your altitude. Alternatively, you could also time how long it takes for the Earth to spin once beneath you (yes, it does spin in-game), giving you a rough estimate of your Railjack's orbital period (time for one orbit), and then use that to calculate orbital altitude, since orbital altitude is dependent upon orbital speed. Of course, this one is only going to be a rough estimate because you have to take into account the Earth's rotation as well. There are probably a few other ways of doing it, but again, my guess is that the answers won't agree. DE probably didn't bother to match altitude to orbital speed. Link to comment Share on other sites More sharing options...
32768 Posted January 7, 2020 Share Posted January 7, 2020 1 hour ago, TARINunit9 said: Follow-up question: Is it possible to estimate distance from an object of known diameter (altitude above Earth) by measuring how much it takes up in your field of view? In other words, if Point A is directly below my Archwing on Earth, and Point B is my Archwing, and Point C is on the horizon, can we use the angle ABC to measure altitude? Or are there too many trigonomic unknowns even with a known (averaged) radius of Earth? I don't quite understand what you are trying to do, but as far as i understand your question, you are having trouble measuring Earth from side to side because it's not entirely in your field of view. You can try to find two landmarks on Earth that both visible at the same time. I don't remember what hemisphere is showing in Warframe, but for example, find Yamal peninsula, choose a point on its coast, then find Baikal lake and choose another point on its coast. Somewhere at coasts, so you can use them as landmarks and you can find same points on Google maps. Somehow measure observable distance on screen, then open Google maps and measure distance between those landmarks at known zoom level. I think it should be possible to find zoom-altitude relationship for Google maps somewhere. Then scale distance you measured on Google maps to distance you measured in Warframe, this scale is scale of altitude you've seen in Google maps to altitude you see in Warframe. Note though that Google maps distance tool is likely to show great circle distance instead of projected "flat distance" that you see on screen, don't let it mislead you. Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 2 minutes ago, 32768 said: I don't quite understand what you are trying to do, but as far as i understand your question, you are having trouble measuring Earth from side to side because it's not entirely in your field of view. No, I'm trying to draw a triangle. Two triangles actually. Sorry for the ambiguity, in my question "field of view" does not refer to video game field of view Imagine one line from the center of the Earth to my Archwing. Imagine a second line from my Archwing to the horizon. Imagine a third line to complete the triangle I figure that if we know the distance of the first line and the measure of the angle, we should be able to determine the altitude of my archwing Link to comment Share on other sites More sharing options...
32768 Posted January 7, 2020 Share Posted January 7, 2020 2 minutes ago, TARINunit9 said: No, I'm trying to draw a triangle. Two triangles actually. Sorry for the ambiguity, in my question "field of view" does not refer to video game field of view Imagine one line from the center of the Earth to my Archwing. Imagine a second line from my Archwing to the horizon. Imagine a third line to complete the triangle I figure that if we know the distance of the first line and the measure of the angle, we should be able to determine the altitude of my archwing If you know length of first line, just subtract radius of earth from it, this will be altitude above surface. Distance from center of Earth to archwing = radius of Earth + altitude. Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 (edited) 1 hour ago, 32768 said: If you know length of first line, just subtract radius of earth from it, this will be altitude above surface. Distance from center of Earth to archwing = radius of Earth + altitude. That's what we're trying to figure out: the altitude. We don't know the length of the first line because we don't know the altitude. Edited January 7, 2020 by TARINunit9 Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 5 hours ago, Firetempest said: You'd have to use the curvature of the horizon and arc degrees and whatnot. The surface is blown up aerial photography. Well after about a hundred different ways of wording my question in Google, I finally found an equation for your method. All we need now is a way to measure the in-game skybox in radians Link to comment Share on other sites More sharing options...
32768 Posted January 7, 2020 Share Posted January 7, 2020 22 minutes ago, TARINunit9 said: That's what we're trying to figure out: the altitude. We don't know the length of the first line because we don't know the altitude. Good point. I can only suggest to know at least something before proceeding. You can try to establish how many kilometers there is in centimeter on screen and go from there. Check out these links: https://gis.stackexchange.com/questions/24786/what-is-my-distance-when-viewing-a-scaled-topographic-map https://www.esri.com/arcgis-blog/products/product/mapping/map-viewing-altitude/?rmedium=redirect&rsource=blogs.esri.com/esri/arcgis/2008/02/25/map-viewing-altitude They don't answer your question directly, but maybe it can be helpful. You need to introduce meters somewhere in your calculations, otherwise you can't get meters from degrees, units won't match. Same way as you can't get kilograms from meters alone. But i think it will be easier to find a matching projection in Google Earth or something and look at eye altitude value there. Link to comment Share on other sites More sharing options...
xarvh Posted January 7, 2020 Share Posted January 7, 2020 (edited) Camera is at 996Km, even considering the coarseness of the measure, it's compatible with the ISS perigee of 408Km. Edited January 7, 2020 by xarvh Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 24 minutes ago, xarvh said: Camera is at 996Km, even considering the coarseness of the measure, it's compatible with the ISS perigee of 408Km. Lemme just measure the pixels... Yeah, thanks to the forum software scaling those pictures to the same size, I think we can call this one closed. We're in the ballpark of 900 to 1000 km when we fight the Kosma Grineer Link to comment Share on other sites More sharing options...
Itsmez Posted January 7, 2020 Share Posted January 7, 2020 the earth is flat Link to comment Share on other sites More sharing options...
TARINunit9 Posted January 7, 2020 Author Share Posted January 7, 2020 12 minutes ago, Itsmez said: the earth is flat sun also confirmed for flat Link to comment Share on other sites More sharing options...
Firetempest Posted January 7, 2020 Share Posted January 7, 2020 (edited) 6 hours ago, xarvh said: Camera is at 996Km, even considering the coarseness of the measure, it's compatible with the ISS perigee of 408Km. Too bad the ground textures are in 10s of miles, not thousands. At least in the area I figured out. They just made it look convincing. They likely looked at similar ISS images and tried to replicate it by only eyeballing it and dialed in what looked best with as little as possible. Fun tidbit: The texture repeats as the ocean mask moves at a slightly different speed as cloud cover obscures the change over time leading to more diversity in landmarks making it look far more detailed and larger then it really is. So seems like they succeed in what they were aiming for. LEO. Edited January 7, 2020 by Firetempest Link to comment Share on other sites More sharing options...
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