Geosynchronous Orbits are WEIRD
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- Опубліковано 11 тра 2024
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This video is about the physics of geosynchronous and geostationary orbits, why they exist, when they don't, when they're useful for communication/satellite TV, etc.
REFERENCES
Fraction of a sphere that's visible from a given distance
math.stackexchange.com/questi...
Orbital period
en.wikipedia.org/wiki/Orbital...
Kepler's third law
en.wikipedia.org/wiki/Kepler%...
Kepler's 3rd law (which can be derived from Newton's law of gravitation and the centripetal force necessary for orbit as mr\omega^2=G\frac{mM}{r^2}, and using \omega=\frac{2\pi}{T}) is
T = 2pi Sqrt(r^3/(GM)) where M is the mass of the central object, G is the gravitational constant. Alternatively, we can solve for r, r = (T^2/(4pi^2) GM)^(1/3) ~ T^(2/3)/M^(1/3) = (T^2/M)^(1/3).
There is a limit (kind of like the Roche limit but for rotations). A rotating solid steel ball or other chunk of metal that has tensile strength (ie that isn't just a pile of stuff held together by gravity like most planets) would be able to spin faster.
Calculate how much of a planet's surface you can see from a given geosynchronous orbit/radius? (Obviously for lower ones you can see less, etc) - d/(2(R+d)) where d is distance to surface, ie, R is sphere radius, R+d is object radius from sphere center.
Let's plug that in with r being the geostationary orbit radius. That is, we have \frac{1}{2} \left(1- \left(\frac{4 \pi^2 R^3}{T^2 G M }
ight)^{1/3}
ight)
Average density of a sphere
ho is given by
ho =M/(\frac{4}{3}\pi R^3), ie
ho=\frac{3M}{4 \pi R^3} aka
\frac{M}{R^3}=\frac{4}{3}\pi
ho.
So we can convert the "fraction of planet surface seen" to
\frac{1}{2} \left(1- \left(\frac{3 \pi}{G
ho T^2}
ight)^{1/3}
ight)
So as either
ho or T\to \infty, the fraction goes to a maximum of \frac{1}{2}. And the point of "singularity" where the orbit coincides with the surface is where G
ho T^2=3\pi, aka
ho=\frac{3\pi}{GT^2}. For a rotation period of 3600s, that corresponds to a density
ho \approx 11000kg/m^3, which is roughly twice the density of the earth. For a rotation period of 5400s, we have
ho\approx 4800kg/m^3, which is basically the density of the earth.
Alternately, if we plug the density of the earth in to an orbit of period 5400s, we get as a fraction of the planet seen:
\frac{1}{2} \left(1- \left(\frac{3 \pi}{G
ho T^2}
ight)^{1/3}
ight) = 0.02
aka 2\% of the earth's surface.
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One thing excluded from the video: if a body rotates REALLY slowly, you would never be able to have a geosynchronous orbit because of being disrupted by whatever it's orbiting (in technical terms, being outside its Hill Sphere). For example, a stationary orbit around Mercury would have a radius of 656,231km, but Mercury's influence only extends out to 175,300km, so even if you placed yourself that far from Mercury, you would be orbiting the Sun instead.
That's actually really interesting. Thanks.
The venus orbit he described is also outside of venus' SOI and wouldn't be possible.
tldr; geosynchronous orbit too far away
What do you mean by "influence"? Gravity's influence is endless. It diminishes with a distance, sure, but at what point you call it "sphere of influence"?
@@Max_Jacoby The Earth's sphere of influence ends where the Sun's gravitational influence dominates instead of the Earth's. Likewise the Moon's sphere of influence ends where the Earth's gravitational influence dominates instead. The gravity for all of them exists everywhere, but spheres of influence are a convenient way of thinking of which one is the strongest there. That's the one you want to do orbital calculations with first.
The animations in this video are fantastic.
Hello destin. Love your vids :)
Just add the ballons and the animations would be complete. Love your channel BTW Destin.
my favourite thing is that the content hasn't changed in so many years of uploading. The music, length and format are all perfect and work together so well
The length has actually changed. In the early early days of the channel, the videos really were approx. 1 minute long. But eventually they more or less covered most of the interesting topics that could be done in that short of a time and started doing videos of about this length where they could cover more topics without watering them down too much.
@@phiefer3 I quite like that tbh, and I consider the "minute" part of the channel name to mean "on the order of a minute" ;)
I wonder if this is silently throwing shade at Veritasium's most recent video...
not to mention the content of this video will also not change either - barring some cataclysmic cosmic event in which Earth gets hit by big enough object to significantly change it's rotation speed, that is
@@vaakdemandante8772 at which point we probably have other more important things to worry about lol
Technically satelite TV wouldn't be too hard to implement even with a long delay of geosync orbit. Since it's just pure upload and download, your TV will simply be delayed by the time it takes to travel. Which isn't a big deal because if you're watching news, does it matter that you got your news 1.5 mins later than someone else? The issue comes when you're talking about communication satellites. Can you imagine having 15,000ms of latency?
The problem is the cost, not latency. Huge dishes, huge transmitters, even further to fly with a rocket with heavier and more electrically hungry satelite.
@@Tondadrd Satelite tv would have been delayed a few decades at best
I think I've played MMO games with more latency than that. Or at least it felt like it.
@@emrek99205 It's the kind of latency where server decides you probably turned off the game and closes the connection. So you get "logged off" pop-up before crash/return to some menu.
@@Tondadrd actually the problem is the problem because a problem is a problem.
fun fact. Moon doesn't have selenocentric orbit. At the distance one should be, you are no longer bonded to the moon but rather to the earth. Also, most lunar orbits are unstable since moon's gravity is unevenly distributed enough that it interferes with low orbits.
Lunar Reconnaissance Orbiter (LRO) began as a circular orbit at 50 km altitude. It has been orbiting the moon for over 13 years now, though in an elliptical orbit to conserve fuel.
@@rickkwitkoski1976 That's what the person you responded to was saying. You have to consume fuel to stay in orbit. LRO carried a lot of fuel with it with the knowledge that it would need to consume fuel to stay in orbit.
@@Ergzay too many people don’t realise the difference between passive orbits and active ones :(
@@kaitlyn__L Ahahahahahahaha 😂😂😂😂😂
There are no _selenosynchronous_ orbits. There certainly are selenocentric orbits.
Lag-time aren't too problematic for TV use. That is mostly one-way transport of information, and as long as there are no faster channel even the deciding point in a tennis-match doesn't get spoilt. The problem is two-way communication where the lag-time becomes too annoying.
I wonder if there are other planetary properties for which we aren't in the goldilocks zone, but other planets are
@@Matthias_Fischer i think he means the planets in our solar system
@@Matthias_Fischer Also the idea of the universe being infinite is currently really only an idea.
There is no rease to not believe in a looping universe or simply some borders. Just that we haven't found any borders or loops so far.
Well titan has liquid methane on it’s surface, that’s a Goldilocks zone
@@sirsanti8408 yeah earth limely had it , but it's also likely that it got oxydized by cyanobacteria during the great oxidation event
Ohh that would be cool to figure out.
The other problem with a "Venus-syncronous" orbit would be that it would be unstable: it would need to be so far out as outside Venus's sphere of influence, and so it would start orbiting the Sun instead of Venus.
Maybe some sort of Distant Retrograde Orbit (similar to Artemis 1) could be "synchronous" but it wouldn't be anywhere close to circular, iiuc it would be sort of "bean-shaped"? and more importantly its speed would change radically at different points of the orbit, moving faster on the day side and slower on the night side. And if that's the case I doubt it would be useful for constant communications with regions of Venus.
Edit: Come to think of it, the kind of DRO I'm thinking of being syncronous might not be possible in certain situations. If it's so far out that Venus's gravity isn't a major factor, then it would need to be on an elliptical orbit around the Sun that happens to have the same orbital period as Venus's year. Which would be incompatible with Venus's day unless the ratio between Venus's year/day is just right.
See also: Hill Sphere
Better question, who the fudge would be down on Venus's surface? Most people would be in floating blimps which travel around the planet much faster (therefor they would be using much closer satellites, but what the heck do you call a satellite in sync with an altitude of atmosphere?)
Cool.
I think that problem is kinda moot anyway. If a planet spins that slow, it would be unsuitable for life as it's surface temperature would be too extreme.
@@azlan194 It doesn't have to be that way though. There's nothing preventing a planet further out with a cooler surface temperature from spinning more slowly. There are multiple planets in the Trappist-1 system, for example, that are in the habitable zone of their star (therefore cool enough for liquid water) but still most likely rotate very slowly
*"We happen to live on a planet... in the Goldilock zone for satellite TV."*
I just learned something this minute.
Any planet or other object that can have a synchronous orbit with a spacecraft large enough to house necessary equipment for satellite TV is in the goldilock zone. That means almost all planets on Solar System including Pluto. Most of the moons too. That is because TV is one way broadcast so the latency is no issue.
@@anteshell "Any planet..."
You must have watched a different video.
@@Blackmark52 Please, go back to school and learn to read. There was quite a many more significant words than just those two you quoted.
For example "Any planet... *that can have synchronous orbit...*"
Further more, I state "almost all planets", which quite literally means that I do not mean those couple of planets that do not have synchronous orbits.
Now, you can either admit to your mistake or double down on being an illiterate idiot. Which one you choose?
@@anteshell "Now, you can either admit to your mistake"
What mistake??? I haven't made any claim. My comment was that I learned something from the video. I have no idea what you are talking about in either of your comments.
@@Blackmark52 Yeah, I can see you have no idea. Not even a slightest of ideas how language works.
Wait... for satellite TV, a few extra seconds delay doesn't matter, does it?
(Signal strength might be an issue though, I don't know about that. And things like (video) calls and internet in general are a different story, but it's hard tot argue we're in the goldilocks zone for those.)
It’s definitely more so the signal strength, but geosynchronous satellite internet is neigh unusable with it’s bandwidth and delay even in Earth
@@sirsanti8408 Even there, the delay is not relevant. TV over the internet is perfectly usable with higher delays. Other than hearing the neighbors celebrate the goal a few seconds before you get to see it, people rarely even notice the delay. But I'll agree on that it is close to unusable with its bandwidth on earth.
A late TV broadcast is not a problem but imagine any kind of duplex (two way) communication. If we were talking via satellite phones, a 10 second delay would be terrible.
Yep, lazy narrator
@@jasper265 we solve this today with buffering
When I was growing up, we had one of those old-school satellite tv dishes that had to physically rotate to be directed at the satellite in orbit. I'm assuming those satellites were geosynchronous because once it pointed in the direction of the satellite, it didn't move, haha. And I got hooked on TV at a young age.
My grandparents had one. It was as large as their house. Crazy stuff. Now we have all this xG technology transmitting not only the televisions but also the flu! How times change.
@@legacysage I hope you're sarcastic
And that’s why geosynchronous satellites in particular (as opposed to satellites in lower orbits) are especially handy; that dish is gonna be cheaper for a given signal strength since you don’t need hardware and mechanisms to rotate it.
@@alexsiemers7898 Doesn't it need to be rotated initially? Also, what if you don't live on the equator?
@@Anonymous-df8it the initial rotation would just be done during the installation. And if the satellite itself is above the equator, then your latitude on the ground won’t matter as long as there’s line-of-sight (it’ll instead just be pointed north or south to compensate)
It’s interesting to think of the geostationary radius as the maximum size of earth before chucks of rock get flung off
its been so many years and his content has never changed, and i love that
Would you be weightless if the geosynchronous orbit is at the surface?
Yes, on the equator. At other latitudes it gets interesting because the "down" gets a leading term defined by surface friction.
Since your orbit is neither expanding or contracting, yes, you would be weightless. Here on the surface we have weight because we're closer to the earth's center mass and what we feel is our orbit colliding with the compressed rock (or whatever) below us.
@@jounikyou would be weightless everywhere but if it s not an equatorial orbit you would drift between 2 max latitude depending on how the orbit is tilted
@@Boss_Tanaka Basically permaskating over the equator of something shaped much like Bennu and then back again - hence the surface friction bit.
@@jounik if you want to avoid surface friction, just jump a little bit and you ll be hovering westbound
Why wouldn't satellite TV work with a 10 second delay? Live events would have a slight delay but my favorite series could very well be seen as long as the signal is continuous.
I have the same question here. Sure, phone calls would be an absolute pain, but TV usually has more delay than that.
Especially in the US for specific reasons
Yeah that part makes no sense
@@fluffigverbimmelt What reasons?
@@Anonymous-df8it only applying to live events, and I mean nipplegate
Geostationary and geosynchronous orbits are fun, but you know what's even cooler? Sun-synchronous orbits! *Almost* at 90 degrees they use the hecking fact that Earth is a bit wider around the Equator to give themselves a little bit of rotation each orbit to stay in-sync with Earth moving around the Sun. It's a really weird quirk of orbital mechanics that lets them do that and it's so cool! Would love to see a video about that from you :D.
???
Let me know when you finish the video
I need Hourphysics, an extended version where Henry just reads all those side notes you can only catch for a fraction of a second in the cc AND goes full ham into the details
That's called MIT OCW :) Physics lectures and entire courses for free!
You didn't mention the case in which synchronous orbit doesn't exist because a body is spinning so slow the resulting orbit is far outside body's sphere of influence and therefor unstable. Usually the case with tidally locked bodies like the Moon or Mercury.
then the3 obects woould be postitioned so no relative orbit.
Mercury isn't tidally locked.
@@shawn4116 technically true, but a 3:2 resonance is too slow as well.
See also: Hill Sphere
If mercury were actually tidally locked an L1, 2, 4 or 5 orbit would do the trick
Great video. I once did a ping via a geosynchronous satellite and was amazed to see just how long the RTT was on the lights on the modem.
Great content as always
Minor nitpick: Satellite TV is possible even with 10 sec delay. Only for real time communication application it poses challenges.
Not only satellite at 280 km altitude would cover 2% of the Earth's surface, but it also would be subjected to atmospheric drag. ISS is constantly pushed up, imagine hundreds of satellites that are even lower.
If geosynchronous orbit was at 280km, the atmosphere wouldn't be as thick either. And even if there was an atmosphere at 280km, it would be as fast as the satellite (on the equator only). A scientific explanation for floating islands!
@@mathiasplans atmosphere would be much more thicker actually. Centrifugal forces would raise atmosphere up higher.
@@Max_Jacoby centrifugal force isn't anywhere near close enough to gravity to have that effect... -.-
@@Max_Jacoby the centrifugal force would whip the atmosphere out into space I imagine. It would be cool if someone simulated it to figure it out
@@irrelevant_noob It is when the rotational period of the earth was just 90 minutes. Earth radius is 6371km. If you'd be weightless at 6650 km above the earth center, then you'd be nearly weightless already at 6371 above the earth center. On the ground.
I love that you're still doing this. Keep it up man. You were on my radar since the "should you hurry in the rain" video
This is the only channel I see post and get excited to watch the amazing crazy physics questions be answered and understood with stick people and I love it keep it up!
Geosynchronous orbits can vary in their longitude as well if the orbits are ellipses instead of a perfect circle. Also, for some bodies with slow rotation rates and a small sphere of influence (like the Moon) it's not possible to have a stationary orbit since you would have to orbit so far out that other bodies would mess with the orbit.
Exactly, the geosynchronous orbit has to lie within the Hill Sphere
If the axies of the orbital elipse vary much, they are not "geosynchronous" according to the normal definition, The nearest point on the surface of the Earth will vary due to the varying orbital velocities.
The nearest point on the Earth is only fixed for geostationary orbits (which are a subset of geosynchronous orbits)
actually you could put your vessel on earth-moon langrage point and have it be stationary
@@absentchronicler9063 stationary relative to what?
Why would satellite tv not be practical on Venus because of the round-trip time? It’s linear receive-only content so all you get is a 10s (extra) delay if you’re watching live events but for everything else (watching soaps or movies or the news) that delay doesn’t matter or can be compensated for
It's so far out that it would orbit the sun instead!
Love this! (I was a satellite technician overseas for 5 years.) Just one additional note: the geostationary orbit appears as a small figure "8" in the sky. Because no one has figured out how to keep a perfect orbit, {north to south and/or east to west}. I know this because if the automatic tracking systems stopped working, every two hours I would need to go out and manually track the dish back onto the satellite.
Keep up the good work.
Excellent information, I never thought about the effect rotation speed has on stationary/synchronous orbital distance.
Satellite TV could still be possible with a long delay, since it's a continuous stream. Satellite telephone or internet on the hand would be a headache.
I’m just impressed with how we can place phone calls and send messages with small handheld sat phones to satellites in geosynchronous orbit since the past decade or so. Prior to that you’d need to use a constellation in LEO in order to keep the size of the handset small.
I am so happy to see a new miniutephysics video! More! Please, bring us more. This is one of my favorite channels. :D
I still remember the day I realised an orbit is just falling fast enough to miss the edge of the planet
"Venussyncronous orbit"? Doesn't Geo just basically mean rock? wouldn't it therefore mean that "In synch with the orbit of Earth (specific)" be Terrasyncronous?
My guess is Terra comes from Latin and Geo might come from Greek "Gaia"?
Geo is usually reserved for the Earth. E.g., “Geo”graphy = study of the earth. “Seleno”graphy = study of the moon.
@@jaimepujol5507 And Gaia is earth goddess
I think rock is something like petra, like the city built in rock or petrology the study of rocks. PETRoleum meaning rock oil etc.
That's a very muddy distinction, partly because language formed long before we knew space existed, and partly because English is actually three languages in a trench coat that are always fighting for who gets to be the head. The stems "geo" and "terra" can both mean Earth (the planet) or earth (the stuff you stand on). "Terrain" for example is used to refer to the surface features of all rocky planets, and "geology" is the study of rocks in general, again regardless of planet. Trying to be prescriptive in language and assign use case to one or the other isn't really a productive exercise when language is a purely descriptive tool. If people know what you meant, then you said the right thing and that's all you can really hope for.
I’ll never tire of this channel. Good job!
This channel was my first sub.. Glad that you're still here educating us Henry..
If the synchronous orbit is really far away due to a slow spin, you also run into the potential problem of other celestial bodies making that orbit unstable. For instance for tidally locked planets, their synchronous orbits would be as far or farther than their 1st and 2nd lagrange points, making it impossible to have a synchronous orbit over any points along the equator, except for the lagrange points themselves which turn into synchronous points, though they are not stable like most normal synchronous orbits.
You should tell the people who put the James Webb telescope at L2 that the orbit is not stable. Might be news to them. Get a current issue of Sky and Telescope, they show the asteroids at Jupiter's L1 L2 and L3 points that have been there a long long time. These are not the Trojans.
1:06 extremely satisfying to watch
I love this kind of learning. Exactly the optimum sequence of informational elements at the optimal pace, as if concepts are circling my mind as my head spins, and don't spin off on a tangent. There should be a catchy name for this principle. Maybe cerebralsynchronous learning. All UA-cam lessons should be like this. Good job.
This video is all around great. Thank you for what you do.
It probably wouldn't be so bad to get satellite TV with a 10 second ping, as long as the bandwidth is decent. Of course, we use satellites for other kinds of signals like Internet and phone communications, and in that case, a Venus-synchronous orbit would indeed be bad.
Cool stuff. I would point out that we don’t need geosynchronous orbits for tv or other telecommunication systems. Starlink shows that, but didn’t invent the principle. Since we have geosynchronous orbits available, we took advantage of that, but maybe it just slowed down development of superior LEO systems. But the “Goldilocks Zone” quip was still fun, if not really accurate.
There's also the problem of cost. If it's going to cost me 300 million+ to send up one satellite, I'm going to send up as few as are viable to make my satellite TV or internet work with maybe one or two backups, and I'm going to make those satellites as beefy as is practical so I can earn back the cost to put them up in the first place.
Starlink just happens to be at the intersection of small enough systems to pack a ton of them onto a single medium to heavy lift rocket, standardization of systems to allow assembly lines, and cheaper launches due to partial reuse. There's a reason Sirius and XM had to merge to survive.
Starlink is not useful. It is not even a good example of non-geosynchronous orbit used for telecommunication.
Firstly, Starlink didn't show anything. We were perfectly aware something like that was possible.
Starlink requires a ridiculous amount of satellites to even get decent coverage, which reduces the eventual quality you can make them in due to production limitations and quantity necessary.
Beyond that they are in a deliberate decaying orbit, which means you are going to have to send up new satellites constantly, which makes the system incredibly expensive to maintain.
Even beyond that, the Starlink satellites still just do Earth->Space->Earth communication, not between satellites. A very inefficient system in most cases.
And even beyond that, the sheer amount of Starlink satellites necessary for a full scale system is insane. Already now it is having severe effects on our ground based space observation. It is making it harder and harder to get good data. It also adds tons of space junk which will make space launches more and more difficult.
Starlink is one of the worst implementation of space based telecommunication we have ever made. The reasons for not having superior LEO systems isn't because of geosynchronous orbits, but rather because there has been made cost/benefit analysis of it many times. It is simply not feasible with current tech / economy.
Yeah, smaller cost threshold to entry can be a factor, certainly. My point is that lack of geosynchronous orbits wouldn’t be a deal breaker, and might lead to other development pathways. Conceivably, the higher initial cost could slow development, but it also might be a stimulus to even bigger technology jumps.
@@thomasr.jackson2940 Geosynchronous orbit has actually lead to a lot of development. LEO is easy to attain with little to no issue, while Geosynchronous requires a lot more, meaning the bigger technological jump we already made.
Imagine if aliens are amazed and jealous at us that we can afford to have geosynchronous orbits.
What if that is the GREAT filter?
Great explanation! Was always inspired by your channel, I started mine to, to support the many people out there struggling to learn!
Thank you so much !!
I have a similar concept in my Physics book
this helped :)
Probably a reasonable simplification, but since the sun is fluid, don’t parts of it have different rotation times? I think I remember hearing that somewhere. Still MinutePhysics probably made the right choice to simplify here, as the general point probably still stands.
@@gregoryford2532 Ha! I missed that! I was watching on phone and must have looked away for that second. Thank you!
@@gregoryford2532 Also thank you for replying with the timestamp. :)
Yes and no. Yes in a way that what you say is strictly speaking true. No in a way that the differences are so small that their effect on the result is negligible. It is somewhat similar as Earth's atmosphere, although much stronger due to not having solid stuff pushing the fluids around. In Earth, both the air and large seas shows some patterns in which way and how fast the fluids generally speaking flow. However, when averaged out, they more about at the same pace as the solid material. In Sun and gas planets the differences in the movement are much larger due to the lack of solids but on average, everything still keeps the same pace.
Also, it spits out so much radio noise that the satellite would have to very powerful for the reception to be good.
So what exactly is weird here i don’t get it
That they're something that isn't common with bodies , but our planet has the ability to maintain them.
02:56 saying a geostationary satellite that is 280km in altitude is "much less useful for communication" is not true. It just means you would need more satellites and the ability to relay a signal between them.
Gravitational couples is something I remember from college, the calculation of which involved integration of all possible inputs to find a rms value. These corrections contribute a small amount as to why a retrograde orbit favors arrivals while a prograde orbit favors departures. Landing heavy, take off light.
It was taught in conjunction with lunar landings and gravity assist maneuvers such as those used later by Voyager. Discussed during planning sessions is the only time I ever heard them used in industry.
Next do an explanation of Lagrange points
If God never intended for me to sell pictures of my feet to a man in Kyrgyzstan, then why did He optimize Earth's geosynchronous orbital distance for satellite communication?
Hi, it seems that the captions are based on the script/notes for this video. Which is kinda cool because they provide more information than the spoken audio, but no so great because they don't actually caption the video, that is, reflect what is spoken. I see in this video and others that you have extensive notes in the description, so having that information in there for the future would be cool! Overall, captions are most helpful when they plainly represent the audio of a video. Thanks for such great videos as always!
I haven't watched minutephysics in a long, long time, but I'm still glad it's still here after a decade
Heliosynchronus Orbits tends to refer to something different than you have said in this video. Usually it refers to a polar orbit around Earth (or another planet), not the sun as you suggested in this video, which precesses through one complete revolution every year and arrives at the same point with the same sun position each day. This is very helpful for weather observation satellites for example, with which we want to observe the same region at the same time with the same lighting each season.
Wouldn't geosynchronous orbits do the same thing?
@@Anonymous-df8it Heliosynchronus is more suited to imaging in some respects than a geostationary orbit, as you have: consistent lighting, it is a much lower orbit than gso (so less energy to reach and better ground resolution), and you can observe whilst centered over a number of different latitudes.
@@thomasblethyn9639 *higher. It would be higher than the moon!
@@Anonymous-df8it I think lower was correct; a SSO (Orbit which arrives at the same position at the same local solar time each day) is around 700km whilst GSO is around 36000km; the orbit that would be higher than the moon is something else - perhaps one with a 365 day orbital period - I don't believe that a stable orbit exists around earth with this characteristic, but I may be wrong; it is possible that there is some n-body system that will result in such an orbit being possible.
@@thomasblethyn9639 1 revolution/year would be slower than the moon, so it would be further away!
I'm willing to bet there would be some perks to having the alternate modes of possible geosynchronous orbits too and in an alternate universe we might be praising those perks and debating how awkward it would be to have the possibilities we currently have... would be interested to know what cool perks a planet might have that was larger/smaller or faster/slower in rotation than what we currently have.
I can think of one example, the earth rotating every 90 mins would mean it would be much easier to get into orbit.
This is why I don't fully believe in the Goldilocks zone. Mamma bear and pappa bear might exist too.
This is nuts, I had NO idea about this. Great vid!
can't imagine the work you put into this
Thank you !!
Venus-synchronous orbit just sounded wrong to me, which made me wonder if there was a different term for it, that was more correct.
Venutio-synchronous orbit maybe??
Then I came up with Venereal synchronous orbit, which is most probably even most wrongerest of them all 😆😆
Venusian synchronous orbits?
Well, if mars gets areostationary, maybe something to do with aphrodite or ishtar, but I've got no idea how to make them work
just call it veneosynchronous?
Im curious how flat earthers explain this
In essence, it is similar to tidal locking, which means that from the moon's perspective it would appear that earth is in a geostationary "orbit" around it even though it is the moon which orbits us and is tidally locked to face us. So to the potential humans on the moon from the near future, from their little moon bases, it would appear to them that earth is this huge geostationary "satellite", which is pretty cool when you think about it. just a neat little thought experiment which i thought would be nice to share.
first time on youtube listening to the audio alone has been less confusing than watching with subtitles
Instead of satellites, just use Starfleet subspace communications. That should fix any planetary geosynchronous problem.
Humanity got EXTREMELY LUCKY with Earth and its properties
yep! With a moon of a decent size etc. Read Isaac Asimov's "The Tragedy of the Moon"
Well, it's more likely that humanity exists BECAUSE of the Earth and its properties
@@LtPulsar true 🤔
This channel is the reason that I love physics
We don't happen to live in a planet where satellite TV is possible. We happen to live in a planet where geosync internet IS NOT. Which means: We just develop whatever tech is useful :P
Our planet has the most lucky gimmicks in the universe. No wonder why we end up appearing here.
Wooo new vid!!
The subtitles were a doozie to try and read but I love the extra info!
What's the overlap like between the goldilocks for life and the goldilocks for satellite TV? A planet spinning so fast that parts of it fly off does not sound very appealing for life, or one spinning so slowly that parts of it get superheated while others freeze.
Are all life-bearing planets suitable for satellite TV? Please, please tell me so!...
I work in satcom on the front lines of operations. Been in the field for a couple years. Its pretty funny how small the industry is. Independent teleports are staffed 24/7 and our customers range widely from major telecom corporations to institution programs, quasi-governmental agencies, shipping industry. We provide the means (antennas) to either transmit or receive RF frequencies to/from a satellite, granting us the many fortunes such as accessibility to internet, radio, gps, we all take for granted. The RF we downlink is run through customer equipment which converts it to a format which we run out of our building via fiber where it is shared within its enormous network. It’s a really incredible field. I enjoy it.
Dunno, I don't think it's an _insane_ coincidence that our day length is somewhere between 90 minutes and 8 months...
We have satellite TV, so it's not weird that we live on a planet where that's possible.
Wow. Whoever planned this one sure was thoughtful!
The round trip delay is (almost) totally irrelevant for television applications. In fact there is already a huge delay, depending on the technology you are using. You can hear that during a football world cup. Different houses erupt in cheers sometimes 30 seconds and more apart from each other. That is, because they probably use different technologies to get their TV signal and these technologies have different delays.
stuff like these makes it even more convincing that we are in a simulation 😅
Thanks for highlighting the geosynchronous vs geostationary difference.
New to the channel, interesting and helpful content, keep it up 👍
2 videos in 1 month? it's a christmas miracle
Those graphics are way cool! Thank you!
I've heard the term Areosynchronous used to describe a Geosynchronous orbit around Mars, so by that logic the Venusian equivalence to geosynchronous would be Athenosynchronous
You mean aphrosynchronus; Aphrodite is the Greek counterpart to Venus, not Athena
@@GODDAMNLETMEJOIN oops, yes you are correct
Another interesting type of orbit around the Earth is the set of Sun-synchronous orbits that are often used for satellites that take images of the Earth. These orbits are around 90 minutes period, pass near the poles, and they are designed so they pass over whatever area has a specific local time of day such as noon, 10 AM, 6 AM, etc. (plus they also go over areas at the opposite time of day midnight, 10 PM, 6PM).
Its also interesting that those sun-synchronous Earth orbits are possible because of the shape of the Earth: en.wikipedia.org/wiki/Sun-synchronous_orbit
One way communication like broadcast satellite TV would be fine. A few seconds Latency wouldn't bother it, the problem comes in two way communication like a call.
Nice video! Not sure about WEIRD in the title though. Best part was the point about Earth being in the Goldilocks zone for satellite TV.
New videos on this channel make me my day
Kerbal Space Program has a third problem: with the planet Duna it’s geosynchronous orbit is preoccupied by its nearly binary moon Ike, so if you put something up there then there’s a good chance you are not going to see it again 😅
umm, doesn't the distance determine the speed needed for a stable orbit? Meaning that if ike is there, then IT is synchronous, so we could just put satellites at other points within the orbit and they wouldn't be affected?
@@irrelevant_noobgood argument
With a roundtrip of 72,000km (or just under) wouldn't that mean signals could bounce off a satellite in
My thoughts exactly!
If there's any Kerbal Space Program players who found this video interesting, I recommend checking out Whirligig World, a planet mod that puts the space center on a rapidly rotating super-earth. (Mesbin) There's a moon in a geostationary orbit that is extremely close to the planet, and in fact that stationary moon (Statmun) has to be held together by tension forces rather than gravity, so you can't land on its equator. As the developer of that mod, it was really cool to see this MinutePhysics video about many of the same concepts my planet mod explores!
One note that i'm surprised you didn't bring up: Venusian geosyncronous orbits are impossible, because the day is longer than the year. If the orbit is too high, it can be beyond the sphere of gravitational influence of the planet, and force you to be pulled away into a solar orbit. Mercury, Venus, the Moon, and all tidally locked worlds etc, all have this problem.) Mars' geostationary orbits are also impractical because you're stuck between two moons and because Mars' gravitational field is somewhat lumpy. You can get some of the advantages of geostationary orbits using lagrange points, but as you pointed out, distant enough stationary satellites are impractical to use.
That is such an interesting insight! Thank you!
3:46 Finally, a fine tuning argument I can get behind!
I was reading about geostationary satellites used for weather mapping a long time ago and it mentioned that you can't just put a satellite anywhere on the equator and have it stay in place. Because the Earth is "lumpy" (i.e. not a uniform density perfect sphere) there are subtle "hills" and "valleys" in the gravitational field along the path of the equator. In this case, the European weather agency wanted a satellite that was exactly centered over 0° longitude, but since that is not one of the stable positions, the satellite will naturally want to drift east or west (I forget which direction). This means the satellite must use fuel to periodically make corrections to put the satellite back where they want it before it drifts too far away.
I studied this in 9th standard, now your explanation made it more clear. 🥰
Amazing how you can produce such an interesting five minute video!
Some people are just simple and easily amazed
Small correction. Satellite TV doesnt care at all about roundtrip times.
Having a higher orbit wouldnt be so much of an issue.
And sure you need a bit bigger antena to receive, but the transmiter is not that much bigger. Because signals through space travel quite easily, its the atmosphere that messes it up.
Just look at any satellite we have sent past the moon with a camera, their antenas arent that much bigger.
Even the ones in voyager aint that big.
Now 2way communication... Thats a different story.
Where have u seen a normal satellite (and by normal i mean one that orbits the@themoon) and one that was sent past the moon to compare those 2? Because it is besides the point, obv the one going past the moon will be bigger by any means
The moon tides very slowly slow down the spin rate of earth.
The rate depends a lot on (possible) ocean currents, depending on continental drift, that can counteract tidal forces on land mass.
Most of the time we had dinosaurs, we also only had 1 big continent, and during that time, the rotation of earth did not slow down over time, because somehow it was in an equilibrium.
What I don't like for an educational video: the caption tells much more than the video
Just so we’ll written. How can you not be entertained while being enlightened. If only school was this efficient and interesting.
This video/topic reminds me of the anthropic principle, if we lived in a planet with no geostationary orbits then they would just be a niche thought experiment and no one would make videos about them
I think most confusion seen in this is that people think of orbiting crafts, and the “relation” they have with the rotation of the earth. Once you realize the rotation of the body basically has nothing to do with the gravitational effects objects have while interacting with it, the easier it is to fully comprehend.
If geo stationary orbits weren't practical the youtube video would be talking about why we don't use them and use some other tech. We utilize what is useful. There are infinite possibilities that aren't useful given our situation.
That was interesting as hell. I never would have thought of any of this...
I love the additional humour in the subtitles!
One thing ived noticed about geostationary satellites is that they only seem to cover up/down to 75°N and 75°S latitude.
So we need to have slower rotation of the earth to cover one whole hemisphere of the earth
It’s called infinite distance. Which means no matter how further u go you will not see more of a round object.
Thanks for the beautiful illustration of how perfectly Earth is positioned in our star system to allow not only life but also geosynchronous orbits - I’m going to use this in my future apologetics! 😊 I am continually fascinated by the ways science itself proves a Creator.