How to Navigate in Realistic Space Travel

Spacedock delves into the fascinating subject of space navigation.
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[@mitwhitgaming7722]

I like the idea of your average star-hopping, rag-tag smuggler in a sci-fi setting actually being really good at calculus, because you would have to be in order to make a living in space.

[@ksevio]

Or they have a computer

[@mitwhitgaming7722]

​@ksevio But that's the thing. If the computer fails, you either have to know how to fix it or do the calculations yourself. Both of which are equally funny to think about.

[@tunguska2370]

Texas instrument

[@exploatores]

@@tunguska2370 yes I got a Ti 83. as long as it gets fresh batteries. it takes almost anything.

[@TheTrueAdept]

That is not likely, as the math required for maximizing dV efficiency will be phenomenally complex, thus requiring computers. People forget that Apollo's computers weren't the main computers; they were there just for 'that final mile,' so to speak. The real computers of Apollo were massive mainframes at NASA that sent data to Apollo. While we've got computers now that can do what those mainframes did _on_ the spacecraft, we're getting to the point where we'll need pretty chunky computers to maximize dV efficiency. At least until we get CG-NTRs (Closed-Gas Nuclear Thermal Rockets, aka 'nuclear lightbulbs') using water up and running.

[@antguy3195]

Han Solo being a disguised super-nerd is quite the funny thought.

[@Edge-wx7hv]

I'm pretty sure it's Chewie who handles the math-y stuff. (Though you're right, I imagine han prefers to be able to keep the falcon's tech maintained himself, so he's probably pretty knowledgeable about the machinery)

[@silverjohn6037]

It's not nerdy when it's a practical skill used to get a useful job done;).

[@hoojiwana]

Han Solo is using a droid brain trapped in his ship to navigate for him. - hoojiwana from Spacedock

[@antguy3195]

​@@hoojiwana However as another person has said, he still has to maintain the machinery. And, correct me if I am wrong, but there have been several points in time when he wasn't accompanied by an astromech. Though I am not the most knowledgeable on star wars so if you are talking about an actual computer in the falcon then I retract my statement.

[@enisra_bowman]

@@hoojiwana and not forget that there is the whole Astromech Droid Class for that task and L3-37 was one

[@TheSaneHatter]

"Wheel, telescope, astrolabe, compass: a ship's a ship" - Doctor Who, 'Curse of the Black Spot'

[@tedarcher9120]

Astronauts on Apollo used an advanced Astrolabe to navigate

[@rfletch62]

"... a tall ship, and a star to sail her by".

[@3Rayfire]

"John Masefield"

[@CathrineMacNiel]

@@3Rayfire Are you sure about that?

[@3Rayfire]

@@CathrineMacNiel I am well versed in the classics doctor.

[@CathrineMacNiel]

@@3Rayfire Then how come you didn't know Row row row your boat? >:(

[@3Rayfire]

@@CathrineMacNiel 🙄

[@marwcelin4022]

The missile knows where it is at all times. It knows this because it knows where it isn't, by subtracting where it is, from where it isn't, or where it isn't, from where it is, whichever is greater, it obtains a difference, or deviation. The guidance sub-system uses deviations to generate corrective commands to drive the missile from a position where it is, to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position where it was, is now the position that it isn't. In the event of the position that it is in is not the position that it wasn't, the system has required a variation. The variation being the difference between where the missile is, and where it wasn't. If variation is considered to be a significant factor, it too, may be corrected by the GEA. However, the missile must also know where it was. The missile guidance computance scenario works as follows: Because a variation has modified some of the information the missile has obtained, it is not sure just where it is, however it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be, from where it wasn't, or vice versa. By differentiating this from the algebraic sum of where it shouldn't be, and where it was. It is able to obtain a deviation, and a variation, which is called "error"

[@LilFeralGangrel]

I need to ask, how difficult was it to type this all up? Good job at any rate!

[@marwcelin4022]

@@LilFeralGangrel I just found a copypasta of it and fixed the errors that's all

[@user-wp2wi1hb7y]

I've seen this exact comment before .

[@charlesparr1611]

This never gets old, but what is the origin of the text? Does anyone know?

[@CptJistuce]

You are so creative and smart, I have never seen this before!

[@Frudu]

All I need is the light of the astronomican. Bless the emperor 🙏

[@danielseelye6005]

Gloria in Excelsis Terra.

[@cyborgspaceman]

With the astonomican and my trusty gellar field, we have no need to fear the dangers of space. Of course, I do not fear at all, having partitioned my unnecessary emotions apart from my cognitive functions. Praise the Omnisiah. 🙏

[@the_senate8050]

"Bröther, I crave lamp!" -several hive fleets

[@CantankerousDave]

In one of the later Foundation books, the main character insists on making the hyperspace jump calculations himself (which can take hours or even days) because he doesn't trust the ship's newfangled "com-pyoo-ter" to do it properly.

[@logion567]

Now I'm reminded of the "Jumpships" in Battletech, and how they can calculate their FTL jumps with a Human or computer. Said Jumps are limited to 30ly at a time, it takes a week to recharge between jumps, but can be accurate to a few Kilometers. The lore blurb in the "Strategic Operations" Rulebook also mentions how very bad navigators can sometimes "misjump" and find themselves several light-years away from their intended location. Said Jumpships usually find themselves with an open Navigator position shortly thereafter 😂

[@kiwiwarlord8152]

I love that you are making a few videos on a bit more of the practical matters of spaceflight. In my studies as a civilian mariner we where taught that gps simply works by caculating our distance to any gps satelite. If you have the exact distance to a minimum of three satelites, you know exactly where you are. The distance is calculated by measuring the time it took the signal to reach the vessel ( usually down to a fraction of a mili-second), As Distance= Speed* time traveled, and we know speed and time, this isn't that hard for a computer.

[@deep.space.12]

One more thing about FTL-capable civilizations is that, when you warp/hop to another point in space, you are seeing starlight, their redshift, and positions, at vastly different points in time. Say, our map of Proxima Centauri's position today, in Earth's inertial frame, is its position 4.2 years ago. And that's the second closest star to us.

[@Edge-wx7hv]

very old stars and exogalactic objects like other galaxies and super-stars etc. are already in use for stellar observations and figuring out where things are. anything outside the galaxy should make for a useful reference point in a pinch, if you don't have local starmaps and whatever you use during FTL for navigation (if thats a thing for your FTL system)

[@tearstoneactual9773]

Big oof. Not only do you have to calculate position by how many reference points, you have to factor in light delay with each one being it's own variable. Which means you also have to track "when" you are, and "when" you left as well, and of course the faster you go the more varied that can be, as well as passing closer or farther to gravity wells. And as @Edge-wx7hv points out, you might use other galaxies and super-stars for farther reference points, but if you make a blind jump, or get sent somewhere way far off from where you expect to be, or beyond your frames of reference, you might well have no way to tell "where" or "when" you are. Though that last situation is probably a pretty far out outlier. And if we're in a situation where we wind up in a different corner of the universe, we've either got that solved, or we've got way bigger problems.

[@ForestRaptor]

This is a concept that I love about Sci-fi. @@tearstoneactual9773

[@Gala-yp8nx]

And then you have to account for stellar drift or end up popping out of FTL in the middle of nowhere.

[@ben501st]

In Star Wars lore, astronavigation information was regularly updated via the holonet. It seems the Empire could have effectively controlled who could travel where by cutting off updates.

[@CantankerousDave]

The Star Wars galaxy being a flat disc simplifies things there.

[@RipOffProductionsLLC]

The Empire didn't control the Astronavigation update system. The neutrality of the guilds responsible for it has been paramount to their business since before The Republic was a thing.

[@RipOffProductionsLLC]

​@@CantankerousDaveit's only a flat disc in artistic representations in soyrce books because pages in books are flat, in-universe it's as 3D as it should be.

[@Lonovavir]

That may explain why about half the Star Wars galaxy is marked here be dragons. The Empire doesn't want people to know what's out there. Or Abeloth?

[@countfizix6415]

You can go a level above and use quasars for extra-galactic (maybe out to order 0.1-1B LY) navigation in a similar manner to pulsars as the ~200 brightest have well defined absolute brightness and distance. These quasars are also incidentally, the reference points the GPS satellites use to estabilish their own location as they are far more fixed in space from our perspective than the sun is relative to stuff like pulsars or bright local stars.

[@VelociraptorsOfSkyrim]

Do you know what would be interesting? A combination between using Quasars and Pulsars within a galaxy. Since Quasars are functionally stationary in the night sky, you can use them like a North Star of sorts, with the Pulsars giving a secondary set of coordinates.

[@willythemailboy2]

@@VelociraptorsOfSkyrim It turns out that pulsars are basically useless in terms of interstellar navigation because the beams they put out are narrow. Even as close as Alpha Centauri you could potentially be out of the beam path of many of the pulsars in an earth-centric database. The location plaques on the space probes mentioned in the video will be completely useless if some other civilization finds them, because they won't be able to see the pulsars used as beacons. Later probes used globular clusters as signposts because they can be seen from any angle.

[@VelociraptorsOfSkyrim]

@@willythemailboy2 That is an unfortunate pickle. Quasars and Globular Clusters, then?

[@KorianHUN]

I worked on a sci-fi world where the main form of FTL navigation was based on measuring pulsars. The navigational computer held a large darabase of pulsars and large stars with information to calculate changes based on age. Naturally FTL would mean the signals from the same pulsar were not the same 1000 and 8000 lightyears from it. Navigational accurace was based on how accurate your pulsar database was. However a small angular difference and any gravitational interference would change your trajectory. To nerf FTL but allow for it as a story element travel required a lot of shorter jumps. Constant readings confirmed the accuracy of the navigational system and the computer automatically adjusted jump direction based on it. This was the way to allow FTL travel even for damaged ships. And traveling to other galaxies required getting the appropriate pulsar and system maps.

[@tearstoneactual9773]

Did it account for doppler shift/light delay? Your point of observation changing would change how "old" the light from your points of reference would be, so you'd be seeing where it "was" not where it "is" now.

[@willythemailboy2]

It turns out that pulsars are basically useless in terms of interstellar navigation because the beams they put out are narrow. Even as close as Alpha Centauri you could potentially be out of the beam path of many of the pulsars in an earth-centric database. The location plaques on the space probes mentioned in the video will be completely useless if some other civilization finds them, because they won't be able to see the pulsars used as beacons. Later probes used globular clusters as signposts because they can be seen from any angle. Quasars would work within a fairly big radius, though.

[@sophietaylor9753]

A realistic star tracking system on a galactic scale would need significant computational power, I think, in order to calculate the movement of individual stars from the positions listed in the ephemeris. Another factor is navigating while travelling at relativistic velocities; you have to deal with non-simultaneous, non-causally-linked events being ordered arbitrarily. You also would have to deal with the fact that new stars are born and old stars die; stars which are in the catalogue might not be around any more, and stars which meet all the criteria for being in the catalogue might not be in them, because they were born after the last update of the catalogue.

[@captainmatthew661]

fun fact i had a lecture from the person who discovered pulsars today. i wish i saw this video first so i could of asked about if she thought of or heard of the navigation use. her name is Dame Jocelyn Bell Burnell if anyone is wondering.

[@localhearthian2387]

About time she got a title for her work.

[@BFVgnr]

I'm currently reading the Frontlines series by Marko Kloos. "Orders of Battle" has the main character's ship sucked into an Alcubierre bubble, where FTL is capable. In human vessels, the farther the system from the entry node, the longer the transit. When drafted along by the alien vessel, they go farther than ever before, and with the shortest transit time they'd seen. For example, the 150 light year transit requires a full 24 hours in Alcubierre. But the alien bubble takes them 900 light years, over a mere 33 minutes. When they determine their position, they use what is referred to as Galactic Positioning, which uses known pulsars as points of reference. The fine points are not addressed, but they determine themselves to be 900LY from Earth space.

[@slimnerek]

That’s a great series. Read all 8 books in like a 3 month span

[@barrywhite8747]

Never read the book I'll look it up. Does the alien bobble in theory work the same as warp bobble? The way you deceive it seems like it.

[@Phrancis5]

GPS is indeed a very clever and accurate form of military navigation that Reagan released to the public after the Korean Air 007 was shot down by the USSR in the early 80's after it strayed into Soviet air space. I was a young child at the time, but flew on that same Boeing 747 KAL-007 on the same route a year prior.

[@RorikH]

Hey, I just thought of the reference-star navigation idea myself, mostly because in Starfield Cora Coe keeps saying, "on Earth people used the stars to navigate, but that doesn't work in space" even though in Space there's... pretty much nothing else to use to navigate.

[@hoojiwana]

Oh dear, its very possible to navigate using the stars, what else would you use! - hoojiwana from Spacedock

[@ooooneeee]

Yet another Starfield fail. Bethesda has fallen so far.

[@originaluddite]

The phrase "Borg know-how" conjures the image of a gruff yet reliable cyborb tradesperson in overalls.

[@deanlawson6880]

For solar system nav, I can see us setting up solar system GPS satellites/beacons in lagrange points of each of the planets, just doing the same type of GPS calculations we do now with satellites around our planet, just on a much bigger scale, and it can be just as accurate, and will move with the planets as they move. For interstellar nav, the only real feasible method has got to be Pulsar nav. Those things are very regular and "reliable", and can get you reliably to another star system, or space based installation close enough to use transmitted beacons from the remote system or installation you are approaching, kind of like a layered series of systems. Serious fast nav computing with multiple redundant backup nav computers checking and cross-checking each other would be essential for doing all of this. This is really interesting for a video topic - Thanks for this!

[@Woodclaw]

I think a great foundation for this subject is Dava Sobel's "Longitude", an essay about how difficult it was to calculate your position at sea during the age of sail.

[@mahatmarandy5977]

If I recall correctly, given how far away, the stars are from here, pretty much any solar system within about 13 ly of earth is going to have essentially the same constellations. Some individual stars may be a little brighter or a little bit dimmer, but their sky is basically the same same as our sky. And again, if I recall correctly, you can ghetto out about as far as 35 ly and still recognize the same constellations we see from here. They will be somewhat deformed compared to what they look like in the night sky, butmstill fairly recognizable

[@hoojiwana]

Yep, but think how many franchises have you going all over the galaxy, and not just pottling about the local neighbourhood! - hoojiwana from Spacedock

[@mahatmarandy5977]

@@hoojiwana oh, I know. To be honest, I’m not sure why I posted that, other than I thought it was interesting. Given how low tech a sextant is, and how old, it’s just sort of fascinating to think that it’d work just as well at, say, Tau Ceti as it would here, and you could even use the same starcharts.

[@Ensign_Cthulhu]

See "First Lensman" by E.E. "Doc" Smith, in which Virgil Samms uses his knowledge of star patterns to roughly locate the position of a drug syndicate's drop station for future detailed reconnaissance. The payoff comes when they detect a signal coming from that direction and have a fair idea of what its significance is.

[@Billchu13]

The falcon has a spirit of rebellion that calculates all the nav math

[@todayletstalkabout6908]

A cool tracking system that was used in the book series "looking slass" by John Ringo wich used cameras located across the entire ship and mouse image movement tracking software to build a location map and track the ships movement across space

[@exploatores]

Wouldn´t navigation in FTL be kind of strange. As youl catch up old signals from places behind you.

[@Edge-wx7hv]

presumably very much yes. you can however do observations, and if you're not worried about making noise, you could use radio-lighthouses to create navigation signals set up so you can tell where you are by which part of the signal was sent when

[@tyrannosaurusimperator]

You'd presumably need to just travel in straight lines, for a set period of time.

[@mattp1337]

IIRC, Harry Turtledove's short story "The Road Not Taken" offers a unique scenario, where alien species with bronze-age-to-medieval technology also have FTL and gravity manipulation. Humanity is exceptional in having completely overlooked the very simple physical effect by which aliens traverse the stars. It's tangential to the story, but the fact that these otherwise primitive aliens navigate across light years by dead reckoning and memory of major stars-no math or computers involved, I don't even recall if they had drawn charts-was a fascinating detail in that unique story universe.

[@wilwatkins2773]

I think it was Wing Commander when I first heard of pulsar navigation. Nice tie to submarines and inertial navigation, a technology that is still critical and evolving.

[@chrisbacon3071]

Still using that space engineers music sound track? Nice 😎

[@Nostripe361]

Kind of like the idea some type of deep space stations that release gps like signals to help a ship navigating the void between star systems

[@ChakatBlackstar]

I remember the Star Trek TOS Technical Manual had a page that summed up how they handled course tracking, with the computer integrating a SINS platform, several elements of what would be needed for dead reckoning(engine output, records, helm response, etc), as well as external systems including the various scanners, a telescope, and a "civil spaceways beam rider" which I'm guessing would be a type of space-GPS system from before we had a term for that.

[@Marinealver]

Even in the Military we say Lost = Dead. That statement is never truer than out in space.

[@dinonuggets7148]

My ways of space travel are called "fuck it we ball" and "I fucking guessed"

[@EridaniOpsCG]

I just wanted to say that your videos have really helped me out with my full-time work modeling spacecraft and my own channel during 2023. Thank you for your videos.

[@goiterlanternbase]

There is an often overlooked aspect of traveling at relativistic speed. The ginormous future cone.

[@bowenmadden6122]

Ooh, this certainly does give me inspiration! In my setting, the protagonists start in a single solar system that doesn't have interstellar travel-well, until the events of the story come along. It would make sense if they mostly used a solar system map & GPS to navigate, and so when the protagonists are stranded in another star system, they would have to learn how to navigate without either method. 🤔

[@michelleshaw337]

One of your better videos - practical and grounded appropriately in some good real science.

[@sundragon7703]

With respect to system or planetary surveys in science fiction, I cannot recall if a story used ship-centric "GPS". The survey ship would be the reference point, then deploy micro-satellites to generate a temporary base map of a planet or system. As the survey obtains more information, the temporary base map would be discarded for the completed survey map.

[@crmesson22k]

Space navigation sounds like a pretty cool occupation

[@PlehAP]

If you are using a sextant and clock to travel between stars, also consider that relativity has time and space dilating as an object approaches the speed of light, which could throw off your calculations for where your destination will be by the time you get there

[@Arashmickey]

On the softer sci-fi side of things: what if you're in a dust cloud or void or some kind of anomaly, could anything get through? Would you be restricted to particular signals? Could you use variations in CMBR, which is supposed to look mostly the same everywhere? Gravity wave stick charts?

[@jaw0449]

Thank you for mentioning 4D! As a physicist, I love your videos, thank you!

[@Nobody.exe50]

I love how many footage of shows you use , great ones to see in the future

[@TehAntares]

This topic suprisingly made me a lot more interested.

[@Nikolai_The_Crazed]

Navigation through the stars would be quite difficult. Light takes time to travel, so the stars aren’t even actually where they appear to be. The view we get of them is from where they were in the past. Meaning you have to predict where they’re headed, and used that prediction in relation to their distance to get a rough idea of where the star is now. While we can predict the movement of these objects, much like the predictions on hurricane movement, that becomes less certain over larger distances. Interference from other objects could make that course deviate in ways you couldn’t predict. For example, let’s say there’s a blue shifted star, and through all the observations you’ve seen, it appears to be moving toward you. You set a course, but when you get there, oops. There was a black hole no one detected, and the star was orbiting that. While it was headed for you at one time, thanks to that orbit, it has now deviated away from your original intercept point. It’s apparent motion may not look very big, but it is now somewhere completely different. Plus, all the stars around you have not changed their positions as well. You are now lost.

[@lc1138]

Much inspirational indeed. Thank you !

[@philrm99]

Excellent discussion.

[@circuitboardsushi]

Internal errors are not the reason you can't rely only on inertial sensors. The problem with inertial sensors is that they can be fooled by gravity. By that I mean they will fail to detect gravity when installed on a spacecraft that is being pulled by the same gravitational field. In order to have accurate dead reckoning it is necessary to account for any perturbations. The inertial sensors can only detect thrust and non-gravitational perturbations, like solar pressure.

[@FranksFilmEcke]

You forgot the real problem: knowing where "you" are and knowing your vector is just one part of the equation of star navigation. The next step is knowing where your target will be. You see a picture of the past (which is only problematic for longer distances) and the target, where you want to be, moves in a 4D space. Additionally, you need to know the way, including sling shot maneuvers, gravitational forces, and fuel economy.

[@feralprocessor9853]

Pretty stunning to see a Pulsar phenomenon.

[@Zamun]

Thanks for the content.

[@LS-001]

1:10 reminds me of a line from the book "The Martian": (Spoilers, I guess?) When making his way from the Hab to the ARES-IV launch site Mark Watney also uses a sextant for navigation. In his log he makes a joke something like, "It's quite funny, I'm standing here on the surface of mars, wearing a high-tech spacesuit. But I'm navigating using 16th-century tools." NOTE: In the book, when preparing for the journey, Watney messes up and destroys pathfinder (which he has been using as his make-shift radio transmitter), therefore NASA can't tell him his location.

[@spikedpsycho2383]

Space navigation is a awkward concept, but the technology they use is no different that what we actually use. The "Inertial Navigation System" operates by use motion and rotation gyroscopes and sensors thus it can determines position, orientation, and speed of the vehicle without using the stars, Sun, Moon, planets or some outside visual reference. This was used by Apollo program to create a computer controlled navigation system. Another method is use of X-ray/Gamma pulsars which permeate across the galaxy, the hyper bright burst of quasars. These objects remain fairly static and their pulse frequency is an ideal method to compare various distances.

[@Monderoth]

For sextant navigation you could create an atlas book of different star maps! Every page could be a different star maps from the perspective of another star, and they could all be calculated by a single astronomer anywhere in the galaxy prior to a starship's voyage. They could even calculate the star maps for unexplored stars too! As long as they can see it in their telescope, they can map it.

[@frankharr9466]

Thank you for pointing out that everything is in motion.

[@SeanStephensDarkElfLX]

Interesting that this comes up on the same day I've been watching about real world problems in GPS spoofing in Commercial flight

[@saturnv2419]

Always find it hilarious GPS essentially started with some tech guy trying to test if general relativity works.

[@modelmanjohn]

No mention of the most bloodthirsty method of the astromonicon from warhammer 40k with the sacrifice of 1000 psychics a day?

[@kenbrown2808]

I would expect a populated space with established travel routes would also use some form of beacon, much like the beacons used in early transcontinental air travel. for a planet, there would be a geostationary beacon "ahead" and "behind" it in orbit, for a star system, one beacon would be enough for interstellar FTL travel, because it wouldn't move enough in the travel time to require plotting an intercept.

[@resurgam_b7]

The end result of this series of sci-fi mechanics and science had better be an announcement that Space Dock has constructed its own space battleship and will soon be casting off from a secret construction station in the lunar shadow to conquer the solar system then the galaxy in the name of all the nerds and sci-fi enthusiasts of Earth!

[@appo9357]

5:02 That episode of Sliders was one my favorites.

[@Paul-A01]

GPS is even cooler because the satellites don't just have to account for the light speed delay But also the relativistic effects of time dilation because they move so fast around the earth. If they kept normal earth time the calculated position would drift by miles

[@stormycatmink]

One issue with using pulsars for navigation, is they rely on the orientation of the pulsars beam crossing relatively close to you. If you moved significantly far (say the other side of the galaxy), the odds the pulsars sweep planes still cross your point in the same way is unlikely, unless they were extra galactic pulsars. (which may be fairly common.. can't remember how well we can see extra galactic pulsars, my brain is mixing them with quasars a bit)

[@thinaphonpetsiri9907]

Speaking of navigating. I’m kinda wonder how many ship’s helmsman in sci fi able to pull off an extreme maneuver with just a touch screen? I mean, think about those USS Enterprise E conn and the Expanse iPad like thingy that the pilot uses, it looks rather hard to use that to control a massive aircraft given how cumbersome they would be.

[@bmobert]

With pulsar navigation, you would also need a spin-down model to figure out if the your relative instantaneous speed. Pulsars slowly change their pulsation speed as their spin slows down. How fast you are going will also change the the apparent pulse rate. Triangulation between pulsars isn't good enough to narrow down your position if you don't know how the light cone from those pulsars are warped because of your relativistic speed. To compensate for that distortion, a good model of the pulsars' ring-down would be needed and compared to known pulsation from a known distance, time and relative speed. The larger the percentage the speed of light you are traveling, the more important this discrepancy becomes, getting very bad at FTL speeds.

[@PrinceAlhorian]

"Pilgrims were the first space explorers and sailors. For five centuries they defied the odds. They embraced space, and for that, they were rewarded with a flawless sense of direction. They could feel magnetic fields created by quasars and black holes, negotiate singularities, navigate not just the stars, but space-time itself. "

[@eugeneloretta5814]

Some of those methods work for low velocities relative to the light speed, get closer to light speed and they don't work so well.

[@justinrita7793]

It’s pretty crazy how all the tools we need to survive in space are there. We just have to figure out what they are and how to use and understand them. I like to believe that if we weren’t supposed to be out in space we wouldn’t be able to even leave earth in the first place. I think of Earth as tutorial island at the beginning of a game. We have to learn as much as we can down here so that way we can apply all of that out there. It’s forgiving here on earth to some degree (please don’t burn me at the stake for saying that, these are just my observations) But out there it’ll require a lot of team work. There wouldn’t be room for prejudices or petty grievances. The bigger picture would have to be the mission. A future for all generations to come. Just like the sacrifices people made before our time. The hope for a better life for those that come after.

[@theaureliasys6362]

Even submarine launched ICBMs use star navigation (amongst other systems, of course)

[@randybentley2633]

It'll be interesting when GPS goes from Global Positioning System to Galactic Positioning System...

[@RiceWD05]

Will admit I fojdn this especially interesting since I am trying to work out my own sci-fi setting, snd navigation being a big aspect since thr ship found herself in another galaxy without good charts. Now of we can get a video on radiation shielding

[@ashtiboy]

what about the newest real life gravity wave detectors that bsacly use lasers via gravty wave vidrations to bascly when disurbed by the menuite difreaces of the lasers pathways caused by gravty waves intracting with the laser beams can be bascly used to detect and navgate in deep space. also they can also detect thsoe gosh darn alein gravity wave ftl drives realy easly too by the way if you got enotgh of them to trangalte where they are bascly.

[@Molikai]

a) Gravity wave detectors are HUGE. And ridiculously sensitive bits of kit. (They can pick up your footsteps from KM away, sensitive.) b) GRavity waves are not regular, repeated events as a rule.

[@chrisbelkosky5466]

Loving the Space Engineers background music

[@h8GW]

Dammit, I'm not the only one who read "realistic space travel" as _"relativistic_ space travel", right?

[@222toastedtoasters3]

yippie space engineers music again 🥰🥰 my scifi origin

[@philjohnson1744]

I love the idea of galactronaughts using aol CD's to make the adtrogation navigation

[@tomaszworoch]

What about orbital dynamics ?! You get the shot from Alex in Rocinante planning some crazy orbital manovers

[@feralprocessor9853]

Right off the bat, navigating the stars is harder than it looks.

[@liamsmith615]

In a story I'm working on the way the characters find out where they are in the galaxy is by which ring they are in, out of nine and going out from the core, and then by use of six pulsars that can be seen.

[@connorhenning786]

I like the Ariadne network used in Gundam Iron blooded orphans, i guess those would be similar to subspace beacons used in Star Trek

[@ush2177]

Hi Spacedock. Could you do a video on a possibility of a real world Homeworld type ship. So is it possible create a mothership that is entirely self sufficient and could be park next to an asteroid belt and mine and build fleets of new ships. The mothership wouldn't have access to a planet so it would need to be built to house anything it would need. mining facilities. refineries/ manufacturing, you would also need to support the crew so you would need on board farms and food processing.

[@sgtsnake13B]

The spacecraft knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the spacecraft from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position that it was, is now the position that it isn't. In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation, the variation being the difference between where the spacecraft is, and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the spacecraft must also know where it was. The spacecraft guidance computer scenario works as follows. Because a variation has modified some of the information the spacecraft has obtained, it is not sure just where it is. However, it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error.

[@SlinkyTWF]

In our latest SF novel, we use pulsars for fixing positions.

[@Arcticgreen]

My own StarWars headcanon: Astromech droids are startrackers, using the stars to determine their EXACT location. Instead of a simple catalog, they use a map of the ENTIRE galaxy!... or as much of the galaxy as has been reliably mapped, anyway.

[@tymek200101]

I wonder if a startracker that checks for paralax of nearby stars could be used to locate within the solar system, a sort of inverse f the method used for measuring distance to stars

[@EliotHochberg]

Are there any spectra from pulsars that could be used to fingerprint each one? Such that if you were traveling faster than like, you could work out which one is which and therefore use that to determine your location? It seems to be that other otherwise for fashion light travel the only alternative is for artificial intelligenceto know the locations of the various pulsars and extrapolate the possible combinations based on their positions and movement although with Fast and light travel, they’re movement relative to each other would make a larger difference depending on how time was dilated.

[@masterSageHarpuia]

Can you do a video on galactic mapping with sci fi cultures that have FTL. The first issue I see is that because the ships move much faster than light in these settings, which means maps need to account position and distance to determine where a Star should be via FTL, rather than the light that would be showing the stars past position.

[@SergeyPRKL]

This is a topic i have always wondered.... But Interstellar travel. WHere the travel time is so long, that the destination stars movement have to be counted accurately, or you miss your target... Not just point at it, To sirius, just point at it and you head for the location where it was 8.7 years ago. You have to count its present speed and heading.

[@ponyote]

Inspired, yes.

[@farkelrysunhope6339]

Will you be doing ship reviews any time soon? Been a while now.

[@griffinschreiber6867]

For the IMUs, of course gimbal lock is a problem.

[@StYxXx]

4:47: 3 billion stars. That's not sci-fy anymore. The Gaia probe has already measured almost as many objects. For almost one billions stars it got the position, speed, heading, color, magnitude. We can visualize our neighborhood pretty accurate and could also calculate our position. Well... if we could travel this far. But even a billion stars isn't much. It's just 1% of the galaxy. There are some neat visualizations out there showing the stars based on that real data. And we didn't even use Borg tech.

[@ThePiousMan]

What about looking into gravity? Relative twards mass of specified gravitational strength?

[@RandomNooby]

Modern high tech dead reckoning is an underestimated level of accuracy...

[@WillofDD]

My solution was using "navigators" telepaths who can detect and map out the surroundings when they're in a sense deprivation type of tank.

[@TotallyNotAFox]

Do they like "spicy" food?

[@WillofDD]

@@TotallyNotAFox Yes. But they have to be melange free, tho. ;)

[@tyrannosaurusimperator]

Do they by chance need a "lighthouse" powered by an immense amount of human sacrifice?

[@Lonovavir]

That would help avoid the Chaos realm and all the problems it causes.

[@therealshadow99]

In a slightly related topic... I've spent a long time trying to find a program that could plot a course between objects in space given an average acceleration value... Or even just a formula to do it correctly, but since it's really hard to get lines in space formulas are super complex and best left to a program that can actually draw the curves that a course would follow. I've still yet to find such a thing though...

[@captainteutonica5474]

The spaceship knows where it is because it knows where it isn't.

[@skrymerU]

If I (a tourist) saw that map and didn't read to carefully, I would just assume they were experiment with some new map design.

[@Ptaaruonn]

In my setting there are extra galactic beacons that are used for astro navigation.

[@Lonovavir]

I just blind jump/warp and rely on plot armor to not smack into planets at warp 7. It's worked so far.

[@patrickmccurry1563]

Technically, white dwarfs can very rarely be pulsars. So far only two such have been found though.

[@feralprocessor9853]

SPACE!!!