What Makes Lagrange Points Special Locations In Space

[@SteveHodge]

As wikipedia says, "In an effort to avoid naming everything after Euler, some discoveries and theorems are attributed to the first person to have proved them after Euler."

[@willemhaifetz-chen1588]

Good point

[@oldfrend]

was euler really that much of a genius? a wonder he's not spoken of with the same reverence as newton.

[@insanitysportal6692]

🤣

[@milkdrinker7]

@@oldfrend Euler was the greatest Mathematician to ever live

[@mathis8210]

That tells us just how bitchy and envious these people were. He figured that shit out, so he deserves the honor.

[@TusharGoyal1997]

Those were some of the most intuitive graphics I've seen when explaining Lagrange points. Well done, Scott!

[@danieldosen5260]

I came here to say the same thing. THESE pictures are worth a thousand words.

[@Allan_aka_RocKITEman]

I agree...👍👍

[@larryscott3982]

Ditto. Without reservation, Lagrange points have never been better described by graphics.

[@jeremystern1471]

Right, Scott is the man. Amazing video

[@petemurphy7164]

Was going to post the same.

[@deboanalagoa8824]

I'm a physics student and I've done the math. But those graphics were really next level. Thanks, Scott!

[@randbarrett8706]

I’m a pixel student and have done the animating but those maths were really next level.

[@mastershooter64]

@@randbarrett8706 The mathematics behind it are really fun! you should try them out.

[@PanzerBuyer]

He lost me at Hi I'm Scott Manley.

[@0sm1um76]

I completed an undergraduate degree in Physics and we never covered Lagrange points or the three body problem. What level of classical mechanics did you do it in, or did you just do it for fun?

[@talesmaschio]

And judging by your nickname I’d guess you’re studying physics at UFSC and lives at Lagoa da Conceição. Did I guess it right? 😄

[@cativillegas]

For a non-science person like myself, these graphics were super helpful to better understand this concept! Just witnessed the launch this morning so I had to look for more information to further clarify L2. Thank you!

[@nakfan]

Same here 😊 Webb is on its way (3rd day) to L2 so better understand it a bit better 😀 Hope Webb will last longer than the estimated 5 years...! Happy New Year from Denmark --- Per

[@techtheta2164]

You are not a non-science person if you're trying to understand it.

[@michaeldunlavey6015]

@Michael Jordan Rosalind Franklin

[@Samuel-hw6in]

@Michael Jordan Fishing I see

[@ddtus]

Does "non-science" mean low IQ?

[@mjmonjure]

Finally, an explanation that is clear, concise, and visually communicative for us lay people. Thanks so much!

[@Sanquinity]

Exactly. I've had trouble understanding how the JWST could basically orbit "nothing" so far, but this video at least gave me a bit of an idea of how it works. Still can't fully wrap my head around it, but at least it doesn't just sound like math magic to me anymore. xD

[@l.mcmanus3983]

It always blows me away what math people were able to work out centuries ago. So much of where we are today and what we are able to accomplish is based on hundreds and even thousands of years of technology and mathematical understanding.

[@r3dp9]

Even more wild, is that they discovered a rule of thumb that requires no math at all. L4 and L5 are located on two equilateral triangles with the long side centered on a line between both bodies. That's easy! (Though NASA points out that the distances involved are large enough that you have to take into account additional gravitational sources, such as the sun and nearby planets.

[@stephenbarrett8861]

Ole Romer was a boss. Calculating the speed of light in tar 17th century.

[@tiemen9095]

​@@r3dp9 Equilaterial triangles with a long side? They each form an equilateral triangle with the two bodies: E.g. Star-planet-L4 and Star-planet-L5 will form 2 equilateral triangles, and these triangles lie within the orbital plane. That perfectly defines the position of L4 and L5 for any system.

[@brendawilliams8062]

With you

[@eventhisidistaken]

They didn't have our tech, so they *had* to work it out on paper. ...practice makes perfect.

[@VeraTR909]

That 3d model representation was great!

[@danielmconnolly7]

Fantasy.

[@jamalalkaabi8]

Lagrange points getting a scott explanation is pretty awesome

[@billhart9832]

Scott, one of your best ever presentations with very intuitive graphics, your impeccable narration balanced between detailed but layman accessible, and kept ever-entertaining with your boundless enthusiasm! Perfectly timed preparing us for the arrival of JWSS!

[@gregor393]

I totally agree - the Webb telescope has sent me searching for Lagrange explanations, and this is great.

[@apotheosis27]

Lagrange Points are incredibly complex concepts. Thank you Scott for helping me understand them a little bit more.

[@chrisrandom7409]

I literally just learned about Lagrange multipliers today, with an exam on multivariable critical points/ extrema on Monday and now its connected to my favorite subject, space, and my day is made

[@MikePaquette]

I'm pleased the youtube algorithm thinks I'm smart enough to appreciate this video

[@stamfordly6463]

First heard of L-points in the '90s game "I-War" where they were used as start and end points for interstellar jumps but I never quite "got" why all of them existed. So thanks for this Mr Manly, you've dissipated a bit of twenty-odd year old incomprehension.

[@Schyz]

What an amazing videogame.

[@AldorEricsson]

@@Schyz Yep. Space sims without that really stupid "space friction" can be counted on one hand, and two of them are I-War 1 & 2.

[@collinbarker]

@@AldorEricsson If you are looking for another space game with no space friction, you may be interested in Space Engineers. It is a building game though, rather than a sim. Think of it as mincraft in space with physics

[@watchm4ker]

The L1 point tends to crop up a lot in sci-fi because of a subtle misconception. Writers assume it's the point where the gravitational fields cancel out. It's not, but it is very close, astronomically speaking.

[@danilooliveira6580]

I think I first heard about lagrange points in Gundam, I was kinda surprised when I found out that the lagrange points were real and that the colonies design were inspired by a concept called O'Neill cylinders made by the physicist Gerard O'Neill.

[@DrUseful]

Brilliantly and clearly explained, and very interesting to watch. Thanks for finally managing to make this, Scott! The rotating potential well graphics were a complete revelation moment for me.

[@DrEnginerd1]

The contour plot max this instantly make sense. Thanks for the intuitive understanding Scott!

[@1000dots]

I thought I already had a good understanding of lagrange points but I learned lots here

[@idjles]

I learnt that L4 and L5 were wells- we didn’t get told about the Coriolis force.

[@1000dots]

@@idjles It makes so much more sense. I could never understand why those points didn't just slowly accumulate dust and debris until it made a big enough object to mess up the lagrange effect. An incorrect theory I'd had myself was maybe 'large' objects can form in lagrange points and then drift away but we'd just never seen it happen. I thought it could possibly be an important factor in planet formation or whatever. Now I know the better explanation: I had been misinformed in a sort of accurate way with the best of intentions. I love when you get to understand something in a new/better way. Anti-science people never understand that science is a self correcting method of understanding things, not a list of facts. Finding out I'm wrong is so damn exciting sometimes :)

[@jeffbenton6183]

Same.

[@matthewb8229]

The nunber of "aHA!" moments of me realizing what you were saying because of the animations was quite high. Really good stuff, Scott.

[@EtzEchad]

Wonderful explanation of the LaGrange points! I knew what they were from the equations, but I never saw the rotating reference from potential wells before. That really makes it clear what's going on. I also didn't know why L4 and L5 were stable. It's pretty obvious that the others wouldn't be stable though. You are a wonderful teacher Scott!

[@r3dp9]

Same here. It all makes sense now.

[@Dragrath1]

@Michael Bishop yeah though it is a matter of timescale even Jupiter's L4 & L5 aren't truly stable just stable enough to still have a bunch of captured bodies from the formation of the solar system over 4.5 billion years later. Though really given enough time no orbit is stable in our large complex universe where n approaches infinity and that is without considering gravitational waves which over vast amounts of time cause orbits to gradually radiate away energy

[@antoninbesse795]

Just watched for a second time; now I really get it thanks to Scott’s well paced authoritative narrative and great graphics. Thanks, and long live JWST!

[@sukuvar]

India's Aditya L1 Mission will reside at L1 for 5 years...L1 signifies Lagrange .

[@mastershooter64]

Why is euler everywhere??? okay I'm convinced that euler's a time travelling math wizard

[@jtn191]

Ben Stein: Euler? Euler?

[@juhajuntunen7866]

Genius got more ideas between breakfast and dinner that aweraje joe in his lifetime

[@mastershooter64]

@@juhajuntunen7866 Lmao ikr!

[@flix7280]

gangsta of the mathematical world

[@olmostgudinaf8100]

Being a genius is not enough. Imagine being born a genius in the 17th century - to peasant parents. You would be sentenced to a life of drudgery, your genius lost forever. The same applies today, come to think of it.

[@Default012]

Just watched SmarterEveryday’s videos on JWST and was very interested in learning more about all the Lagrange points. Thanks for the video scott

[@chrismusix5669]

Too.

[@maksphoto78]

I think Scott, Destin, Physics Girl, and Amy Teitel should collaborate to make one of a kind of a video!

[@mikefriend1514]

Methinks Scott and Destin track each other’s orbits!

[@thomascharlton8545]

Thanks Scott! Now I have a much better understanding of the stability of the Lagrange Points. Likely not capable of a complete understanding but I do now have a “better” understanding. Orbital mechanics is basically simple yet mind numbingly complex.

[@dandan1364]

None of the other videos about Lagrange points make any sense … just guys retelling what they heard without understanding anything. I think you understand this stuff and explained it well. Thank you.

[@deepakgogoi5975]

Came here today after the successful launch of India's Aditya L1 Solar Observation Mission, for an understanding of Lefrange Points! Looking forward to another enlighting telecast on the subject soon. Cheers!

[@nicholasgold9021]

I cannot wait for the James Webb. I hope the fuel it has on board miraculously lasts much longer than it is supposed to.

[@grantexploit5903]

I wonder if it'd have any use in an end-of-life eccentric Earth orbit or Heliocentric orbit...

[@erideimos1207]

@@grantexploit5903 Yes when it finishes the 12 year mission, if it can, it's supposed to stay in a heliocentric orbit and keeping reporting on any fly-bys.

[@StarkRG]

"We accidentally added a second fuel tank so we figured we might as well fill it."

[@sovo1212]

Let's hope Starship to make refueling easier.

[@Tudarc]

The fuel is planned for 11 years but the gossip is that they think they can get quite a few more years than than. The most significant factor is the Mid Course Correction (MCC) planned for 12.5 hours after launch. If it occurs on time it won't have to dip into the L2 station keeping fuel. If the MCC gets delayed for any reason it will eat into the fuel budgeted for the science mission causing the mission to be shorter.

[@jeremynolan4681]

Thank you so much for this. My layman mind has been struggling with this for 2 years while reading about and watching videos on the James Webb telescope. This is simplest and most easily understood explanation of the Lagrange points I've found.

[@Xenosplitter]

I've known about Lagrange points and had a basic understanding of what was going on, but the visualizations at 5:35 really made it click! I think it helps I've been recommended that one video on flipping a sphere inside out, but with the combined gravity wells diagramed as deformities on the object's surface having the "bowls" (although bowls in this diagram aren't Lagrange points themselves), "saddles", and "domes" I finally pieced it together! While I'm not using the proper terminology each time the surface "inverts" a point exists where a theoretical marble would fail to fall out of it's place.

[@user-AdamSmith]

That time lapse of the Earth from the Sun's perspective as the year cycled was really fascinating.

[@NotAyFox]

By far the most comprehensive description of Lagrange points I've seen so far.

[@Yezpahr]

I've seen a hundred of these explanations, but now I finally understand it.

[@xXCatalystic37Xx]

Always love a good Manley explainer

[@clearlyepic9958]

This video so simplified the concept of LeGrange Points! Thank you Scott!

[@RijumanSen]

amazing graphic representation without overly oversimplifying. Awesome video.

[@prodanman]

Thanks Scott Manley. Best Explanation Of Lagrange Points. Happy You Even Cover Coriolis Effect That Nobody Else Covers. Thanks For All You Do For Us Science & Space Geeks

[@darrenmclellan6712]

Thank you for a well-done explanation Scott. It's not easy to wrap one's head around this but you have helped immensely.

[@fiveoneecho]

I remember writing simulations of this after taking multivariable calculus… Such an awesome problem to work on as a challenge!

[@TusharGoyal1997]

Perfectly balanced, as all lagrange points should be!

[@kukulroukul4698]

spiffing brit

[@marvnuts]

I understood that reference.

[@cedriceric9730]

Just like my...

[@EclecticFruit]

Gravity is a perfectly balanced system with no exploits whatsoever

[@positivelysteve]

I don't think I've had a better understanding of gravity wells than I did watching this video. Thank you, Scott, for all the science knowledge you impart so seemingly effortlessly.

[@randyfriend7474]

Mr. Manley, superb video. I’d never seen 3-dimensional depictions of “gravitational warping” but your video showed this. The L-points were expertly shown and described. Thank you!

[@cstenzy9167]

First learned about Lagrange points through one of the cards in Terraforming Mars, great to have an in-depth explanation!

[@ramji102]

Thanks, finally I understand why India Named Aditya L1 ( sun exposure mission), We are proud have say our Indian scientist made theoretical knowledge in practically applied and make the founder Proud...

[@dracula3811]

Great visuals and explanation of lagrange points. I understood what they were before but the graphics helps me with the comprehension considerably.

[@zachhouliston4508]

The way you explain complex concepts and make it so understandable and enjoyable is phenomenal thankyou scott

[@bookingsessential]

Agree with the previous comment... I've seen the whole "big black trampoline with a heavyweight in the middle" explanation before... but this was the first time it made complete sense... Seriously.... Great Job!!

[@bhnuc]

Indian here. Came after our space agency ISRO launched a Sun probe this morning named Aditya-L1 which will stay at Lagrange 1 point.

[@TusharGoyal1997]

Interesting to see both Lucy and JWST having their missions/orbits focuced on Lagrange Points!

[@UnshavenStatue]

There are dozens of spacecraft at SEL2, JWST will certainly be the most famous one. My personal favorite there is Gaia!

[@olmostgudinaf8100]

And SOHO is at L1. I thought Kepler was too, but could not find the reference. I must have misremembered it.

[@ivoivanov7407]

@@olmostgudinaf8100 Kepler telescope wasn't on L point, but on "trailing heliocentric" orbit. That is, it is a bit farther from the Sun than Earth, with orbital period of ~373 days.

[@kishordinkarsonar91]

And Aditya L1 of ISRO

[@magmaticly]

Interesting note: James Webb is going to orbit the Sun - Earth Lagrange point, not just park in the centre of it, because it needs to peek out of the Earth's shadow once in a while to get some Sun to power its stuff.

[@Markharlan95]

SM is a national treasure

[@felttip4431]

For me, L1 was the only one that seemed intuitive - it's the point when the gravitational pull of the two smaller bodies are equal and opposite, so they cancel each other out. Your motion graphics helped me to finally understand the rest of them, especially L4 and L5. Thank you!

[@Scripture-Man]

I just wanted to know what Lagrange points were and thought a 14-minute video would be going into too much detail. But I was captivated by the clear explanation and great graphics. Seems I got caught in a Lagrange point of my own.

[@randycastleberry3194]

That weird shadow on the Sun sphere almost convinced me I had dead pixels on my display.

[@shreeniwaz]

Thank you for this lucid explanation of a very interesting scientific fact. As India has sent it's first Solar mission 'Aditya' L1, the significance of the L1 helps to understand the purpose of the mission..👍🏻👍🏻

[@jonathanjanzen8501]

Instant thumbs up! I’ve been waiting for this video!

[@dmzone64]

Nice, serious. No crazy, easy speculation... You, Sir, are a breath of fresh air and got yourself a subscriber.

[@rectorsquid]

I had to look at a few videos and websites before someone showed why L4 and L5 are where they are. The gravity-well images made it so much more clear than other sites and videos. Thanks!

[@geofthompson3844]

It's so much like fluid dynamics. Hearing this stuff really does help illustrate the concept of spacetime. It's literally a sea, but without water or even matter. Orbiting a lagrange point is like surfing a sea of nothingness 😎🏄‍♂️.

[@brendawilliams8062]

Not nothingness is avoiding chaos.

[@edstirling]

1:53, just casually witnessing the end of the world.

[@Briggsby]

Could you put a pair of radio telescopes at Earth's L4 and L5 points and use interferometry to get an effective dish size of only slightly smaller than Earth's orbit?

[@AldorEricsson]

@@gamerfortynine Not really a problem, just sync them all using the same set of quasars, then factor in gravitational time dilation. The tech is around since 1990s.

[@insanitysportal6692]

Short answer: yes Slightly longer answer: but it's not easy Slightly longer corollary: and it's prohibitively expensive

[@jamessheridan2142]

You could add in telescopes to this at the L1&2 points stabilized by solar sails and sharpen up your results.

[@jamessheridan2142]

@@gamerfortynine Sounds like a job for one of those new fangled computers they got in them there big city's.

[@DrDeuteron]

@@AldorEricsson I now quasars are fine for navigation, but are the fast enough to synch the phase of a radio wave?

[@geoffreydowen5793]

being a luddite I had to watch this twice; I think I got the jist of this though so at the age of 64 I continue to be educated. love your channel your ability to simplify astrophysics , my bro is the physicist in oil though . thanks Scott top marks . fly safe yourself regards from the UK .

[@markmarco2880]

So much education in a single video. Thanks for teaching me how to chill in a group of orbital bodies.

[@targaryenXoolf]

Indian Space Organisation just sent a satellite set for stationing at L1 point to study The Sun. exciting times.

[@harrystuart7455]

I have to say, the visualisation here is absolutely superb. You've given great physical intuition for how Lagrange points and their (in)stability work without having to rely on any dense maths

[@FabioCalissi]

the most dangerous is Lagrange Point 5 where Solomon, Zeon's stronghold, is located

[@cbst6w5]

Side3, if I’m not mistaken.

[@FabioCalissi]

FWIK L1 = Side 4 L2 = Side 3 + A Baoa Qu L3 = Side 7 + Luna two L4 = Side 2 + Side 5 L5 = Side 1 + Side 6 + Solomon

[@cslloyd1]

Incredible effort on this presentation.

[@ScottSlooper]

That is the best visual/graphical discussion of LaGrange Points I have ever seen. Thank you!

[@johnc.195]

Well done explanation and animation, thanks for sharing. Not that Euler's mathematical feats weren't amazing enough, but is there any way of knowing if Euler worked on this 3-body problem during the latter period of his life when he continued to do cutting edge math while blind? Also, the JWST was inserted into its L2 halo orbit today. Kudos to all.

[@jeffcox4538]

Scotty; Honestly, "The" coolest video you have produced! As an ex SSBN submariner. Launching bad things into space if not necessary I learned a bit about physics and orbital mechanics. Thank you for being a nerd and a DJ like myself. BTW I miss the "Night a DJ saved my life." Off of your bookshelf!

[@soundjudgment2150]

Well that’s the most interesting thing I’ll see today. Thanks Scott. Great animations also. Makes me want to run a simulation with two “tethered” particles orbiting on opposite side of the L4 or L5 to see if it cancels out orbit instability at all

[@friedhelmmunker7284]

Jupiter Trojaner are on T4 and T5. Stable position.

[@chochonubcake]

The best description of LaGrange points I've seen. The one weakness is the inclusion of the Coreolis force (which of course isn't a real force at all) when that comes in, you should hit pause and compare this picture to Earth-bound artillery: the L4 and L5 points are continually leaving the orbiting object behind as they revolve about the large object.

[@shaggyhereagain]

Thanks for this. This was required before the launch of Aditya L1 to students like me who are just undergrad freshman and many people who are interested in the Earth- sun space system

[@ianthomas7139]

These get a role in the Neal Stephenson book “Seveneves” where some characters use Lagrange points to head out of the gravity well and go after a comet without burning insane amounts of propellant. Great book, be awesome to have Scott review it and some of the orbital mechanics used within it.

[@walshrd]

Read up on your history of the original halo orbit mission, ISEE-3. After it completed its mission, it was sent out on another mission to the comet Giacobini-Zinner in 1985. That mission to the comet was very successful.

[@georgelionon9050]

I got the idea of JWT going for L2 is also because it has earth's protective shadow shielding it from the sun, being in a position of permanent eclipse, because it needs to be cool for the infrared telescopy to work. Otherwise, L4/L5 would be better choices, no?

[@georgelionon9050]

@@bnightm okay, so now why is L2 chosen then for this? as L4 and L5 are much stabler wouldn't that mean a much longer period of operation? Or is it just than L4 and L5 are more difficult to reach making the additional fuel spent to stay stable in L2 not worth it?

[@markshumate78]

@@georgelionon9050 L2 was chosen so that the JWST can occlude both the sun AND earth (and moon?) with one heat shield. The infrared wavelengths that JWST will observe will be affected by the heat from the Sun of course, and even the earth (and moon for all I know). So having the JWST in an orbit such that a single heat shield can ALWAYS occlude the sun and earth is a great help

[@georgelionon9050]

@@markshumate78 I see makes sense, thank you

[@maksphoto78]

"Hello, it's Scott Manley here." - That's how you know you're gonna have a good day, watching an awesome video.

[@trixer230]

I love how far science communication has came! Lagrange points used to be so uknown about to the common public I could use it as a password, and It was my go to "noone will be able to answer this" trivia question! I love how in just 30 or so years the adverage person now knows what these are!

[@adamdagosto570]

I'll bet this video is getting a ton of hits these days! Great work putting this together. Thank you!!

[@conors4430]

Really neat, first came across this terminology when listening to the Apollo 13 flight controller tapes on KZbin, that’s when it actually clicked in my head that as a spacecraft rises further and further towards the moon it slows down like a tennis ball at the top of it ahrc before it falls, the aim is for it to have just enough Velocity that it crosses the LeGrange point and starts falling towards the moon. I never totally understood how it all worked until I realised that

[@RockChalk263]

There isn't a Earth-Moon LeGrange along the path Apollo 13 would have taken to get there. (Remember, the Apollo craft doesn't fly to the moon in a straight line, but rather a parabolic arc) The Sun-Earth L2 is several times further out from the moon's orbit. What you're referring to is the Apollo craft slowing down as it leaves the earth's sphere of influence and speeding up as it enters the Moon's and starts "falling" back down.

[@GregiiFlieger]

Play Kerbal Space Program and these things just fall into place :-)

[@conors4430]

@@RockChalk263 fair enough. I just assumed it was the halfway gravity point between two objects

[@D3emonic]

The moment when you wish Scott would release a new video... to realise an hour later, he did. Thanks!!

[@ammobake]

For some reason I’ve always disliked the idea of gravity being depicted in a flat 2D context. But neat graphic!

[@_Mentat]

Possibly because the reason objects fall down the gravity wells is because of gravity. These "rubber sheet" explanations are effectively saying gravity works because of gravity.

[@jaknap1]

Best explanation on KZbin of the Lagrange points. Easy to follow and the graphics are amazing. Thanks!

[@dispater5023]

Scott, you're doing humanity a whole world of good with these videos. Keep up the great work.

[@Clyman974]

Wow I can't believe they named a point of space after a ZZ Top song

[@ArKritz84]

Damnit, I should go to bed, but now I *have* to listen to some ZZ Top! 😂

[@hodor3024]

beat me to it.

[@RCAvhstape]

RIP Dusty Hill, gone to the great Lagrange point in the sky...

[@jimleane7578]

I asked myself "how, how, how, how?" Now I know. Thanks Scott ☺️

[@hughbrackett343]

They got a lot of nice girls out there.

[@glenn_r_frank_author]

I was wondering... as the Mars Rovers all had to take some time off from activity because of the Solar conjunction... Has anyone ever proposed putting relay communications satellites at L4 and/or L5? so we could send a signal AROUND the Sun to Mars? or is that just not worth the expense and time? Better just to wait out the conjunction? Seems like if we ever put settlements or manned missions on Mars we would need this though.

[@user-si5fm8ql3c]

A relay out ar L4/5 that needs to relay all the way to mars would be a gigantic technological challenge. First of all, you need a huge, light weight radio dish, its very likely that a spysat operated by the US Airforce has a dish with a diameter of 100m, big enough for our purposes, but no one is sure if and how it works, state secrets and all. Secondly, you need a very powerfull amplifier to boost the signal, with large solar panels to power it all, further adding mass and complexity For now, and even for martian bases in the future it might be easier to just wait out

[@Demobot1]

@@user-si5fm8ql3c You would have a bigger problem of fuel. How would you refuel a relay station that far out?

[@user-si5fm8ql3c]

@@Demobot1 You would not need to, L4 and L5 are stable points, what little force is required could be easily generated by solar wind vanes, without needing any fuel

[@Demobot1]

@@user-si5fm8ql3c all the Lagrange points are stable. But fuel is still needed to reposition the antenna to point to Mars or wherever.

[@user-si5fm8ql3c]

@@Demobot1 no, any deviation from L1-3 is not countered by a sufficiant corrective force, staying at L1-3 costs fuel, at L4-5 the corrective force is big enough that you can stay there without spending fuel. Pointing to mars can be done with big panels that catch the solar wind to generate torque, its not much torque, but you can supplement it with reaction wheels for more accurate pointing.

[@hak5129]

Here after Aditya L1 launched!

[@TheWeatherbuff]

Thanks for the explanations, and the added bonus of the models and graphics. Now even us mere meteorologists can make sense of this stuff! Excellent vid!

[@triaxon3791]

Thanks, this helps me wrap my head around this a lot better, The motion graphics really help. Gr8 job man(ley).. 😀☮

[@kshitizmishra5845]

KZbin recommended this to me, after India's mission to the sun

[@georgeford6056]

Lagrange points are special locations, but not as special as that shack outside La Grange.

[@throwawayavclubber7269]

They've got a lot of nice girls.

[@KimoPollock]

Hmm ... I was always taught that Coriolis is an effect rather than a force on spherical bodies e.g. what causes hurricanes and such. I was also told by another professor that there is no Coriolis effect in space after I asked if space is warped, shouldn't there Coriolis effects? He paused and then said paused for a long time and finally said no. I was skeptical of his answer, but other than that, he was one of the best professors I ever had.

[@JustFamilyPlaytime]

The Coriolis effect is best described as pseudo-force arising in a rotating frame of reference. The question "is there are a coriolis effect in space?" comes down to your choice of reference frame. Seen from outside we see the sun rotating and the planets orbiting and there is no coriolis effect. Seen from within, that is from the reference frame of the sun or any of the orbiting bodies, there will be a coriolis effect!

[@olmostgudinaf8100]

"Effect" and "force" are basically the same thing. The most famous "force", gravity, is an "effect" of space-time curvature.

[@KimoPollock]

@@olmostgudinaf8100 if force is measured in Newtons, what is the measure of the Coriolis effect? Momentum?

[@olmostgudinaf8100]

@@KimoPollock Coriolis force is measured in Newtons, too. Look at it this way. Coriolis "effect" means an object moving in a rotating frame of reference follows a path different from "expected". If you wanted it to follow the "expected" path, you would need to apply a "force" to it. A force with the same value but opposite sign of the Coriolis force. Measured in Newtons.

[@jesterlead]

I'm like a Pakled and Scott Manley is like Jordy La Forge. You're smart. You make us go!

[@g4ifx]

Brilliant explanation without over-simplifying - great job!

[@ashokreddy2982]

It's where India is trying to set it's mission thing to observe sun

[@Jason-gq8fo]

Does earths elliptical orbit affect this in anyway? And the fact that our elliptical orbit changes over time around the sun?

[@DrDeuteron]

you just have to add a little time dependence (cyclic, ofc) to the potential surface, with the rotating and radial part coupled via L = const.

[@fluxcapacitor]

Why does a 3rd strong gravitational potential appear to exist beyond the couple Sun+Earth at 06:20, all around them? The 2D spacetime surface should on the contrary be Lorentzian (Minkowskian) i.e. almost flat as a plateau beyond these two gravity wells. Actually as the wells become asymptotically flat to infinity, the Solar well should really extend with smaller and smaller curvature at a greater distance from it, an no "annular well" all around §that is shown in the animation) should exist at all. This is non-physical. But it would destroy your illusionary explanation for the L2 Lagrange point.

[@fluxcapacitor]

This makes me think that your 2D rubber-sheet analogy is fundamentally flawed, as the highest point of the curve of a "Mexican hat potential" diagram is NOT a stable point, it is on the contrary the _least_ stable point in such a system. It's like putting a needle so it stands straight onto its pointy tip, perfectly vertical, then taking a picture of it before the needle falls in any direction, saying: "See? The vertical position is stable". No, it's not. It is a very _unstable_ one, by definition. The real explanation for the Lagrange points lays in tides.

[@LuxTheSlav]

You are fundamentally misunderstanding what the surface represents. The grid is synced to the rotation of the bodies to more easily map the centrifugal force, all participating bodies are assumed to be in orbit, as they must be for any of it to make sense. The curvature is a sum of both gravitational and centrifugal forces, not just gravity. Therefore, the fall-off on the outside isn't another gravity well surrounding the system, it's centrifugal force overpowering gravity as you get further away from the gravity wells. It's true that any tiny force in L1, L2 and L3 will destabilize any body there, but calling them the most unstabile points is absurd - theoretically, a needle could balance on those points for an indeterminate ammount of time, whereas all the rest of the surface is sloped, preventing any balance whatsoever. So how is the former less stabile than the latter?

[@fluxcapacitor]

​@@LuxTheSlav Of course the top of the hill is not less stable than its slope down further! I was not comparing this place to the slopes on either side of the needle, I compared the convex part of the hill to the concave gravity wells created by the stars and planets, which are truly points of stability. Your needle is like a ballerina making a pointe on the highest part of a spherical balloon. Yes, it's the "most stable part of the balloon". As obviously, the dancer can't put the tip of her toe on the sides of the balloon... but instead of the top of a balloon, she'll be more comfortable doing it in a bathtub to begin with!

[@LuxTheSlav]

@fluxcapacitor Well yeah. The most stabile point in the system is in the centre of the sun. I just don't see how that's relevant.

[@fluxcapacitor]

​@@LuxTheSlav Yet it's very simple​. The most stable point is the Sun, yes, because it creates a stable gravity well. The planets then, less massive but they also generate stable gravity wells. None of the Lagrange points are gravity wells, that's just the point I made you are nitpicking about. They're the “least worse” points than the rest of space (which is "a slope" everywhere else). This is the top of the balloon. We can try to position things there of course, regularly correcting their trajectories because otherwise they will always slide towards the slopes, where they would clearly deorbit. Because they are not stable points per se.

[@pjeverly]

Brilliant video. I’ll echo a lot of the comments saying that the presentation and graphics make this very complex subject much easier to understand. Please keep up the great work.

[@nicholaswilliams8220]

This was the best illustration of Lagrange (Euler) Points I've ever seen! Thanks, Scott!

[@Navneet_100]

waiting for ISRO Aditya L-1 launch .....letz go

[@Keavon]

I've still always been confused: how does L3, L4, and L5 work in the real solar system, which isn't just three bodies? At the distance to L4/L5 and especially L3, the gravitational pull of the Earth must be extremely small. How come other bodies, like Jupiter and Saturn, don't play a much larger influence than Earth does on the entire opposite side of the solar system (L3) or as far away as the sun is (L4/L5)?

[@RutvikMarathe327]

Well there's a L3, L4, L5 for each of the planet-sun pairs. Earth-sun will have its own Lagrange points, as will jupiter-sun, etc. Although you are correct in saying that even at something like the Earth-Sun Lagrange points, Jupiter and Saturn will still cause some gravitational perturbations to those orbits

[@dykam]

My uneducated guess is that it only works if you either adjust for them, or those influences are nearly negligible at those points.

[@TheNasaDude]

Because the distances are huge and each planet remains the dominant body well beyond the Lagrange points. Don't be fooled by the usual visualisations where planets are all amassed near the sun. This video makes a good job of showing actual proportions: kzbin.info/www/bejne/sIOWepqZaLebnMk

[@TrueThanny]

First is the fact that gravity varies by the inverse square of distance, so its effects go down very fast as distance increases. Second is that the dominant gravity in the relationship is from the Sun, which is more than 1000 times more massive than Jupiter, as well as closer to the L4/L5 points.

[@toriknorth3324]

Intuitively, I would think that an object placed at a lagrange point is most affected by planets that are in orbital resonance with the object. If we look at an asteroid in, say, the earth-sun L4 point, the earth and the sun would both pull on the asteroid with basically fixed force vectors (in a rotating reference frame with the sun and earth fixed). Each other planet would have a varying force vector that partially cancels out when you integrate it through time. The orbital resonance causes the earth to have a much larger effect on the asteroid than non-resonant planets would.

[@sudiptechnical368]

Finally Our ISRO🇮🇳❤️ has successfully put Aditya l1 probe to the Lagrange point 1❤️

[@DrZond]

Very clear explanation of a concept that is difficult to visualize! Well Done!

[@davecarsley8773]

Very cool. After 50 other videos trying to explain it to me over the years, your video has finally given me at least _some_ decent understanding of why Lagrange points work!