I had this exact question when they first announced that they were going to put a lunar space station in a "near rectilinear halo orbit" and immediately did some research on it. It was so new at the time though that there wasn't much that explained it well, in fact the wikipedia article at the time was only a couple sentences stating it was chosen as the orbit for the lunar gateway without any explanation as to what a "near rectilinear halo orbit" even is. This was a great explanation, thanks for the video as always Scott.
As an aerospace engineer this is without doubt one of the best explanations I have ever seen anyone do on any space subject. This might also be one of the smartest and most practical missions I have seen NASA do in a long time. I'm actually a critic of the Gateway. At time I think people get so wrapped up in trying to do more they forget the basic tasks. I see this in every industry not just aerospace. I think the Gateway is way too complex for what's actually needed for Lunar Mission Support. All it needs to be is a place to dock vehicles and transfer fuel, cargo & crew. One of the main reasons Apollo worked was they broke the process down into viable segments allowing them to specialise on the vehicle tasks. The CSM had a primary task, get them there and get them back. The LM had the task of getting down and getting up. The CSM didnt need to worry about landing legs and the LM didn't need a heat shield or parachutes. Yeah they got cross purposed on CO2 filters, but they solved that. What it allowed was the CSM and LM teams to focus on there actual task AND IT WORKED. I think they are overcomplicating the Gateway and Artemis and the vehicles they need. That complexity is only going to make things a lot harder, a lot more expensive and the only winners will be the contractors.
Great explanatory video, Scott. What’s also interesting is that this cheap precursor, proof-of-concept mission, was also not NASA’s idea; if I’m not mistaken, the company(s) involved came forward with the idea unsolicited to NASA, who was smart enough to accept it.
You correct, it wasn't a requirement to have the unmanned cargo test landing, SpaceX threw that in. Imagine a hundred ton's of stuff waiting for the 1st human landing
The third stages of Apollo did a 6 minute burn to go from orbital velocity to escape velocity. This is much smaller so it is taking a week and many small burns so to grab as much speed as it can from the Earth "gravitational dwell" to employ for the lunar injection. I only hope the tiny engine does all it is asked to do to reach escape velocity. Thank you Mr. Manley for all the explanations...
I don't begin to understand the maths or orbits, but, as someone who lived through the Apollo programme, it just seems amazing to me that a little rocket like the Electron can fly to the moon!
@pyropulse I'm sure you know exactly what I meant! No idea where you're from, but if it's this side of the Atlantic - I was channeling Thomas the Tank Engine...
Wow...phenomenal video. Great explanations as I've come to expect by Scott, but the animations, charts and other graphical representations of the ideas and concepts discussed really made this content easily digestible.
Amusing that I basically did a simpler version of this for my communication network in KSP. No fancy Lagrange stuff of course, but I always put one relay satellite in a really high elliptical polar orbit and then 2 or 3 around the equator to communicate with stuff on the ground.
That's what makes it fun to watch!! Spacex launches are almost getting boring now with how routine everything is. At least they have good video production to keep me watching.
@@Titter2 Yeah, that's what happens when your thrust to weight ratio equals one! However, we should see a lot more of these when the Starships come in for "landings"!
I’ve been interested in Scott’s videos for a few years, but this… THIS is the most fascinating thing I’ve seen in a long while. This makes me want to break out my old Mathematica models.
5:10 Oh wow, I just realized this orbit's eccentricity is almost exactly what I had done in KSP with RemoteTech when I first went to the Mun! For the same reason too: It minimizes comms downtime 😁 Though I didn't know about NRH orbits at the time, so my relay sat was instead put around Kerbin with the highly eccentric orbit. This was an easier/cheaper launch since it didn't need to fly so far, and it meant all of my crafts going to the Mun could use lighter/weaker antennae 👍
Sadly, halo orbits of all types do not function in KSP - KSP uses one-body patched conics for gravity (only the most important / nearest planetary body affects you at a time), and halo orbits depend on two-body phenomena. (Unless KSP had a major physics overhaul since I last played!)
@@kvt-dev Not in stock mode, no, but there's the "Principia" mod for KSP, which changes from patched conic to n-body physics. I believe KSP2 is also going to have an overhauled physics engine, but IDK if n-body will be an option out of the box.
this is absolutely amazing, where can I learn the astrodynamics behind stuff like halo orbits and lyaponov orbit and stuff? is there a good book or something?
This is the best explanation of this orbit I've seen so far. I don't understand why the description on NASA's website is so poorly done. If I don't find a better one soon, I think I might make a more clear visualization of it myself.
Was trying to work out this NRHO business last night and thought- you know who would explain this well? Great vid and good work on the telepathic request system
Thanks for the explanation of the near rectilinear halo orbit and why it was chosen. As an Aerospace Engineering undergrad, I did a fair amount of orbital mechanics, but this was way above the undergraduate level orbital mechanics.
Thanks Scott. I looked at your channel earlier to see if you had done a video on this and didn't see anything. Just got home from work and a perfect time to watch your video on RLs Capstone launch.
Scott, Relativity question for you. Since we know that gravity affects time, and we also know that the moon's gravity field is 'lumpy', is it possible that a LPS (Lunar Positioning System) based purely on satellites in Lunar orbit could be less accurate than is possible on Earth?
I mean, they figured out a stable orbit around the moon. With all the data you need for that I'd think they know how to account for time dilation in LPS's systems
Even with Earth's gravity on the ground vs. at the height of GPS satellites, the effect is only about 45 microseconds per day. The moon's gravity is much lower than Earth's so the effect caused by the lunar gravities variations would be miniscule by comparison.
The Earth is lumpy too, so time corrections have to be sent to the satellites every now and then. There's no reason why the same couldn't be done from Earth to an LPS satellite.
Thanks for this video! Finally it is down to our man Scott Manley again to explain this thing in a way that normal people can somewhat understand it! Pls keep up the good work!
Slight correction for video... The simulation used to explain halo families and NRHOs from 3:10 to 4:05 is not FreeFlyer. It is actually the Deep Space Trajectory Explorer. Source: I wrote the software and made the original video content.
A fascinating video Scott, must confess I'm a little dizzy, think I need a second beer and watch it again. This research is hard....................... :o)
Seems like "cornerstone" would have been a better name for the spacecraft... I mean.. this is first block of the "Gateway" project ... a Capstone is usually put in last when building a "gateway" right?
1:16 thank you i was looking for this info after the launch and none of them make me undestand it. Lets see if my fav technical space youtuber solve my doubts. Cherrs.
Brilliant as always,..but I have , what I hope isn't a silly question? I understand the clear advantages of a Near-Rectilinear Halo Orbit. However, does this mean the spacecraft going to the moon will be unable to utilise a free return trajectory (FRT) for the spacecraft in the event of an engine failure? Of course, I am thinking of the Apollo 12 scenario where the FRT was necessary to return the astronauts back to earth (understanding the DeltaV required to leave the Moon's Gravity was achieved utilising the LEM Engine). Just curious?
Hi Scott. Great explanation. As a mathematical physicist can you explain the utility and 'reality' of "imaginary" numbers, especially in regard to orbital dynamics. I've a friend who rejects the whole concept of "i". As math is so integral to space science and technology, perhaps your viewers would enjoy a short dive into the validity of math, perhaps with a special nod to "i". For my own part, I'm a non-Platonist retired engineer, who sees all math from integers to transcendentals to "i" as wondrous human constructs that reveal much about the structure and working of our reality.
EXACTLY how Heywood Floyd described aerobraking over Jupiter in the movie "2010"! Only to have added "But the ones who put the numbers on the paper aren't here."
Thanks for putting this out Scott. But this Capstone sattlelite will eventually run out of fuel due to adjustments tho. The Lunar Gateway will be a GOOD step towards us being able to fashion a permanent Lunar Base, then Ship building facilities in Space, as launching Ships etc. from Space is MUCH MORE FEASABLE/CHEAPER utilizing WAY LESS FUEL than launching from Earth. Thus facilitating our expansion into Space. Even tho this is all in the future but, NECESSARY!! Is the HLS truly the future of our Spaceflight? My money's on Space-X!
Almost makes one think that the companies that suggested the Gateway were looking for something that could make them a pile of money without them having to deal with the more challenging tech required to actually land on the surface.
Excellent explanation, Scott. Thanks so much. I heard there were some communication problems for a while, but that they were resolved. I've also read that it arrived into the NRHO just a couple of days ago. Can you do an update on the mission's progress at some opportune time?
Someone on Ars Technica explained that both SLS and Orion do not have enough Delta V to get to the Moon's surface and back to Earth. This is why the Lunar Gateway station is needed. Problem is, building and maintaining such a station is very expensive and has drawbacks compared to a direct Earth-Moon access with more powerful spacecrafts, were a station is eventually built just on the Moon's surface instead of (also) in NRHO. There seems to be now a broad agreement among experts that a solution using just SpaceX's Starship would be far more economical in the long run, even if it takes longer initially to complete the Starship development and make it human rated for launch and return. Such a solution would dispense with Gateway, SLS, and Orion completely. Apparently the Artemis program was adopted as a technical and political compromise, and at the time it was not known the something like Starship would be available relatively soon.
Starship is a liability to the Artemis program Depending everything on it would spell almost certain doom for any near term accomplishments Orion, SLS and Gateway are really the only near term systems we'll have available this decade
@@brokensoap1717 But why even want to go to the moon in this decade if it is only possible with those three systems that are expensive and which will soon be superseded by Starship based solutions anyway? Why spend a lot of further money on SLS+Gateway (only Orion development is already finished) when we know with high certainty that these systems will be outdated in 10 years? And note that Starship could be used much earlier as a replacement for SLS/Orion/Gateway if we initially don't use Starship for launching and returning humans from/to Earth. I think we could launch and return them using the Crew Dragon or Starliner spacecrafts where they switch to/from Starship in LEO. At least I know no argument why this would not work. I think this solution would only take marginally more time than the current Artemis which uses both SLS/Orion/Gateway and Starship. And it would be much cheaper.
9:00 (table of orbit options) the occultation thing seems a bit overblown. Can't one place a satellite or two in orbits to relay communication? Other than that the NRO seems pretty decent. 0.5 day journey to the moon vs. some of the other orbits with up to 3-4 days seems to be its major trump rel. to the other orbits with "feasible access from Earth with Orion", whatever that means. Is DeltaV the limitation there?
Yes (for various reasons including history, cost, etc.), and regarding relays they are expensive and complex (at least compared to no relays), making them hard to justify when a relatively easy to reach orbit eliminates the need for them.
@@emilybraswell4570 If we are aiming for a permanent presence on the moon, satellites seem a pretty desirable component. Also, the Chinese have their magpie. Surely we could manage one. even commercial entities are venturing to send missions to the moon, and compared to the total cost of Artemis I really don't see a satellite or two as a hefty financial consideration.
@@FredPlanatia Perhaps, but this means a satellite is not *required*, and if said satellites go down for some reason you still have Gateway. That said, I do believe at least one lunar satellite constellation is planned (albeit not by NASA).
Interesting. solving the three bodies problem has yielded some fascinating results. If we apply some of those 'halo' rectilinear orbit zones to the Sirius system as high probability zones for finding if Sirius C actually exists ( and helps explain the eccentricity of the system ) , then perhaps the James Web telescope could used to efficient extent for that purpose
just so everyone knows, "near rectilinear halo orbit" is when the orbiting object is orbiting the PLANET and making near passes with another orbiting body. basically, while you can think of it as orbiting the moon as an oblong orbit with a really big apoapsis, you can also think of it as an orbit around the earth that is also being affected by the gravity of the moon, actually you should think of it as the latter because that's what it is, regular orbits around the moon aren't tidally locked to earth and i'll explain: it's not just a standard orbit around the moon, it's using earths gravity to remain tidally locked and the moons gravity to raise and lower itself along the ridges.
CAPSTONE is using a Ballistic Lunar Transfer, id love to see you go over that. It seems like a very intresting low energy transfer. Thanks for the video!
When the lunar gateway is on the close approach and on the turn around the North Pole of the moon would they experience a Centripetal force much like a car going around a turn where they would be feeling a forced against the walls of the lunar gateway? If anybody can answer this I would appreciate it. Great video!
No, they will feel no 'gravity' or sense of acceleration even when buzzing the north pole. The astronauts and their space station would, given the same starting position and velocity, independently follow the exact same path through space. Gravity Independently acts on the astronauts and the space station to make them follow an orbit, so there is no 'cornering force' like one would feel going around a corner in a car. Conversely in a car the force that the car exerts on you is the only reason you Follow it around the corner instead of continuing in a straight line.
both astronauts and surranding them station will be in "free-fall" - situation where external gravitational forces are not countered by any reaction (exactly as in the case of people in ISS). In fact, what we commonly desribe as expirience of "eart gravtiation" is in fact expiriencig reaction force (puted on our feets).
Is there any chance the gateway might be able to get a glimpse of webb? obviously not close enough to see it clearly but might get a glimpse of the sunsheild reflecting?
So when a rocket launches from earth to rendezvous with the lunar orbit, is it going to be aiming to meet at the point of lowest angular velocity around the mun (apogee)?
I’ve been waiting for an in-depth explanation of this orbit. Had no idea how complex it would be
I had this exact question when they first announced that they were going to put a lunar space station in a "near rectilinear halo orbit" and immediately did some research on it. It was so new at the time though that there wasn't much that explained it well, in fact the wikipedia article at the time was only a couple sentences stating it was chosen as the orbit for the lunar gateway without any explanation as to what a "near rectilinear halo orbit" even is. This was a great explanation, thanks for the video as always Scott.
He literally lectures rocket science in laymen terms
As an aerospace engineer this is without doubt one of the best explanations I have ever seen anyone do on any space subject.
This might also be one of the smartest and most practical missions I have seen NASA do in a long time.
I'm actually a critic of the Gateway. At time I think people get so wrapped up in trying to do more they forget the basic tasks. I see this in every industry not just aerospace. I think the Gateway is way too complex for what's actually needed for Lunar Mission Support. All it needs to be is a place to dock vehicles and transfer fuel, cargo & crew. One of the main reasons Apollo worked was they broke the process down into viable segments allowing them to specialise on the vehicle tasks. The CSM had a primary task, get them there and get them back. The LM had the task of getting down and getting up. The CSM didnt need to worry about landing legs and the LM didn't need a heat shield or parachutes. Yeah they got cross purposed on CO2 filters, but they solved that. What it allowed was the CSM and LM teams to focus on there actual task AND IT WORKED.
I think they are overcomplicating the Gateway and Artemis and the vehicles they need. That complexity is only going to make things a lot harder, a lot more expensive and the only winners will be the contractors.
@@tonywilson4713 Not to be too cynical, but I do have to wonder just how much input from said contractors they started with.
As ever, Scott breaks down the jargon into a clear and elegant explanation.
It was clear as mud to me. That's not Scott's fault though.
Did not expect to learn so much on this one. Title should have read 'Orbits 101"
Try orbits 302.
jesus christ this guy has 1 mil subs only 5 likes on comment
Title did not do it justice.
so jesus is interested in space lol
Hi Jesus, Great to see you are still following all the new space stuff!
Great explanatory video, Scott. What’s also interesting is that this cheap precursor, proof-of-concept mission, was also not NASA’s idea; if I’m not mistaken, the company(s) involved came forward with the idea unsolicited to NASA, who was smart enough to accept it.
You correct, it wasn't a requirement to have the unmanned cargo test landing, SpaceX threw that in. Imagine a hundred ton's of stuff waiting for the 1st human landing
Awesome visualizations and great breakdown of the concepts!
The only person so well informed and informer is Scott.
Fly safe in the Cirrus!
The third stages of Apollo did a 6 minute burn to go from orbital velocity to escape velocity. This is much smaller so it is taking a week and many small burns so to grab as much speed as it can from the Earth "gravitational dwell" to employ for the lunar injection. I only hope the tiny engine does all it is asked to do to reach escape velocity.
Thank you Mr. Manley for all the explanations...
India used a similar method of "plenty of passes" before sending their first probe to orbit Mars.
The Little Engine That Could. At every relight it's thinking "I think I can, I think I can..."
they're probably going to use a bunch of small burns since unlike apollo you can take your time
I don't begin to understand the maths or orbits, but, as someone who lived through the Apollo programme, it just seems amazing to me that a little rocket like the Electron can fly to the moon!
@pyropulse I'm sure you know exactly what I meant! No idea where you're from, but if it's this side of the Atlantic - I was channeling Thomas the Tank Engine...
Wow...phenomenal video. Great explanations as I've come to expect by Scott, but the animations, charts and other graphical representations of the ideas and concepts discussed really made this content easily digestible.
Amusing that I basically did a simpler version of this for my communication network in KSP. No fancy Lagrange stuff of course, but I always put one relay satellite in a really high elliptical polar orbit and then 2 or 3 around the equator to communicate with stuff on the ground.
Top tier video! it answered all the questions I had about how this orbit works and why NASA chose to use it.
Thanks Scott, great explanation as always.
So glad they pulled through. Rocketlab is getting good at launching, but I'm still nervous every time, especially with NASA missions.
That's what makes it fun to watch!! Spacex launches are almost getting boring now with how routine everything is. At least they have good video production to keep me watching.
@@Titter2 You can always watch some Astra launches to break up the monotony. Never quite know what you are going to get. Lol
@@zacrintoul I don't know if you saw that one drifting sideways a while back, but that was the craziest launch I've ever seen.
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@@Titter2 Yeah, that's what happens when your thrust to weight ratio equals one!
However, we should see a lot more of these when the Starships come in for "landings"!
Very interesting, the only thing missing was the deltaV differences for moon landings from the gateway to the surface between the different orbits.
Look at 9:00
@@ImieNazwiskoOK I missed the deltaV requirment to LLO at first
I’ve been interested in Scott’s videos for a few years, but this… THIS is the most fascinating thing I’ve seen in a long while. This makes me want to break out my old Mathematica models.
Scott,
Orbital dynamics are fascinating, can you address the burns necessary to get into this orbit?
play KSP
So cool to see FreeFlyer on your channel, Scott! Really informative video - the NRHO is going to be a game changer for the industry.
5:10 Oh wow, I just realized this orbit's eccentricity is almost exactly what I had done in KSP with RemoteTech when I first went to the Mun! For the same reason too: It minimizes comms downtime 😁
Though I didn't know about NRH orbits at the time, so my relay sat was instead put around Kerbin with the highly eccentric orbit. This was an easier/cheaper launch since it didn't need to fly so far, and it meant all of my crafts going to the Mun could use lighter/weaker antennae 👍
Sadly, halo orbits of all types do not function in KSP - KSP uses one-body patched conics for gravity (only the most important / nearest planetary body affects you at a time), and halo orbits depend on two-body phenomena. (Unless KSP had a major physics overhaul since I last played!)
@@kvt-dev Not in stock mode, no, but there's the "Principia" mod for KSP, which changes from patched conic to n-body physics. I believe KSP2 is also going to have an overhauled physics engine, but IDK if n-body will be an option out of the box.
@@eddievhfan1984 the way I understand it, it will be mostly simple dynamics, with some n-body approximation for the binary planets.
A way for constant communication between machinery from the Earth to the Moon. Brilliant video as always Scott! 👏
Shackleton has permanent, Direct line of site to earth, via gateway isn't permanent, is further & involves a relay.
We really don't hear enough about Rocket Lab, great vid
Where did you get all of the animations!? I super appreciate how it shows ECI and MCI frames side-by-side
The graphics are just amazingly wonderful.
this is absolutely amazing, where can I learn the astrodynamics behind stuff like halo orbits and lyaponov orbit and stuff? is there a good book or something?
This is the best explanation of this orbit I've seen so far. I don't understand why the description on NASA's website is so poorly done. If I don't find a better one soon, I think I might make a more clear visualization of it myself.
Was trying to work out this NRHO business last night and thought- you know who would explain this well? Great vid and good work on the telepathic request system
Really great summary. Fantastic description of the orbits involved without getting too technical. Well done.
Just thinking, if something in that orbit only needs
Cant wait for the day some one annouces they are going to put a sattelite in a near rectal orbit around Uranus.
Sigh 😂
Lame old joke. Show some respect.
I think Blue Origin would be most suited to the task, ut can you imagine the erection they would require for a full insertion?
And the probe should be powered by Fast Argon Tunneling engine :D
Damn it, Jim! I’m a doctor, not a celestial navigator!
Thanks for the explanation of the near rectilinear halo orbit and why it was chosen. As an Aerospace Engineering undergrad, I did a fair amount of orbital mechanics, but this was way above the undergraduate level orbital mechanics.
One of the most interesting and synthetic videos produced about orbits. Congrats Scott
Best description of this orbit that I've seen, makes so much sense now. Thanks Scott!
Thanks Scott. I looked at your channel earlier to see if you had done a video on this and didn't see anything. Just got home from work and a perfect time to watch your video on RLs Capstone launch.
Scott, Relativity question for you.
Since we know that gravity affects time, and we also know that the moon's gravity field is 'lumpy', is it possible that a LPS (Lunar Positioning System) based purely on satellites in Lunar orbit could be less accurate than is possible on Earth?
I mean, they figured out a stable orbit around the moon. With all the data you need for that I'd think they know how to account for time dilation in LPS's systems
the difference should be negligable.
But maybe measurable.
The relativistic effects of the lunar MASSCONs are absolutely negligible...
Even with Earth's gravity on the ground vs. at the height of GPS satellites, the effect is only about 45 microseconds per day. The moon's gravity is much lower than Earth's so the effect caused by the lunar gravities variations would be miniscule by comparison.
The Earth is lumpy too, so time corrections have to be sent to the satellites every now and then. There's no reason why the same couldn't be done from Earth to an LPS satellite.
Thanks for this video! Finally it is down to our man Scott Manley again to explain this thing in a way that normal people can somewhat understand it! Pls keep up the good work!
6:48 Apollo:
Do not go gently t'wards our satellite,
Rage, rage against the lumpiness of the flight.
Slight correction for video... The simulation used to explain halo families and NRHOs from 3:10 to 4:05 is not FreeFlyer. It is actually the Deep Space Trajectory Explorer.
Source: I wrote the software and made the original video content.
Thanks Scott, perfect timing. I heard about the Capstone launch and have been wanting to learn more about the orbit.
The third stage still has to complete a final main burn to get the satellite into it's orbit. Hopefully all goes well!
Well if things don't go well now is the time since this is just a satellite and not a rocket carrying people
Best explanation of NRHO on the internet. Thanks!
Thankyou! Finally. I've also been looking & waiting for these explanations. I'll watch this 100 times I reckon.
A fascinating video Scott, must confess I'm a little dizzy, think I need a second beer and watch it again. This research is hard....................... :o)
Fascinating, Scott! Well done!
Excellent explanation, and fascinating! Really breaks it down well. Thanks for the graphic animation too. Very cool stuff. 👍
Today’s lecture was awesome.
He should be a professor in astrophysics.
Good luck Scoii! Thanks for the report. 👍
It took me thee Times Watching that Video to make a map of these orbits in my Head - but now it makes sense :))
The same number of times it took for me to figure out the movie "Interstellar".
Thanks. Nobody is really covering this. Its a big development.
Seems like "cornerstone" would have been a better name for the spacecraft... I mean.. this is first block of the "Gateway" project ... a Capstone is usually put in last when building a "gateway" right?
Ok, but can you make that as an acronym
Ah, in 0g you can build from the top down if you want to!
@Scott Manley If you try hard enough there should be something
@@scottmanley I guess there is no "Up" in space so... I suppose you can start with the Capstone.
You and Anton Petrov are just the best!
Thank you good sir!
the classic stuff that only Scott Manley can do and explain with such understandable finesse
Superb explanation, Scott. You knocked it out of the park yet again!
Thank you Scott for making that perfectly clear.
Thank you. That was very informative. I knew what they were testing, but not the why or any specifics.
I absolutely love these explanations and the graphics you provide.
Great content, Scott.
thank you for the clarification, I had no idea there was so many different options for orbiting the moon
1:16 thank you i was looking for this info after the launch and none of them make me undestand it. Lets see if my fav technical space youtuber solve my doubts. Cherrs.
Brilliant as always,..but I have , what I hope isn't a silly question? I understand the clear advantages of a Near-Rectilinear Halo Orbit. However, does this mean the spacecraft going to the moon will be unable to utilise a free return trajectory (FRT) for the spacecraft in the event of an engine failure? Of course, I am thinking of the Apollo 12 scenario where the FRT was necessary to return the astronauts back to earth (understanding the DeltaV required to leave the Moon's Gravity was achieved utilising the LEM Engine). Just curious?
Great video on Artemis and Moon Orbit station orbits. I never understood the original dicusions but now I do. hanks for making this clear.
Hi Scott. Great explanation. As a mathematical physicist can you explain the utility and 'reality' of "imaginary" numbers, especially in regard to orbital dynamics. I've a friend who rejects the whole concept of "i". As math is so integral to space science and technology, perhaps your viewers would enjoy a short dive into the validity of math, perhaps with a special nod to "i". For my own part, I'm a non-Platonist retired engineer, who sees all math from integers to transcendentals to "i" as wondrous human constructs that reveal much about the structure and working of our reality.
Everything I know about space science I learned from you and KSP. I wish all my school teachers were Scott Manley.
"This stuff (NRHO) is dynamite on paper."
Scott Manley, 2022
EXACTLY how Heywood Floyd described aerobraking over Jupiter in the movie "2010"!
Only to have added "But the ones who put the numbers on the paper aren't here."
Very clear explanation of a complex topic. Thanks, Scott!
One of your best, because it is so timely. And well done.
Rectilinear? Damn near killed 'er!
Was waiting for this one. Very informative thanks.
Thank you for another awesome video. Space community love!! 🤖🧡
Excellent overview as always Scott. Someone smart should catalog your videos into a course on space exploration and physics. Well done!
Excellent video. Most informative - as usual, but exceeding even your 'usual'.
I really appreciated the illustrations of an NRHO.
Beautiful explanation Scott, thanks 👏
Nice but how exactly do you get to this orbit? Could you simulate that in ksp?
Thanks for putting this out Scott. But this Capstone sattlelite will eventually run out of fuel due to adjustments tho.
The Lunar Gateway will be a GOOD step towards us being able to fashion a permanent Lunar Base, then Ship building facilities in Space, as launching Ships etc. from Space is MUCH MORE FEASABLE/CHEAPER utilizing WAY LESS FUEL than launching from Earth. Thus facilitating our expansion into Space. Even tho this is all in the future but, NECESSARY!!
Is the HLS truly the future of our Spaceflight? My money's on Space-X!
your understanding is the opposite of the actual facts, longer duration, exposure, hazard, greater expense etc via gateway
Another great video, packed with interesting knowledge. Thank you Scott.
Well explained. Thanks for the great graphics.
Its amazing how much more ambitious and faster the Apollo program was despite having far less knowledge and technology
Almost makes one think that the companies that suggested the Gateway were looking for something that could make them a pile of money without them having to deal with the more challenging tech required to actually land on the surface.
I expected you would cover this orbit and do a great job. All that simulator time is an excellent extra background.
With such a high eccentricities, how safe is the orbit if it has issues with solar pressure, small leaks, bumps, ect.?
Excellent explanation, Scott. Thanks so much. I heard there were some communication problems for a while, but that they were resolved. I've also read that it arrived into the NRHO just a couple of days ago. Can you do an update on the mission's progress at some opportune time?
Brilliant, I always learn so much from your videos Scott, Thank You.
Thanks for explaining this subset of orbital mechanics.
Thank you for explaining in a way anyone can understand it
Someone on Ars Technica explained that both SLS and Orion do not have enough Delta V to get to the Moon's surface and back to Earth. This is why the Lunar Gateway station is needed.
Problem is, building and maintaining such a station is very expensive and has drawbacks compared to a direct Earth-Moon access with more powerful spacecrafts, were a station is eventually built just on the Moon's surface instead of (also) in NRHO.
There seems to be now a broad agreement among experts that a solution using just SpaceX's Starship would be far more economical in the long run, even if it takes longer initially to complete the Starship development and make it human rated for launch and return. Such a solution would dispense with Gateway, SLS, and Orion completely.
Apparently the Artemis program was adopted as a technical and political compromise, and at the time it was not known the something like Starship would be available relatively soon.
Starship is a liability to the Artemis program
Depending everything on it would spell almost certain doom for any near term accomplishments
Orion, SLS and Gateway are really the only near term systems we'll have available this decade
@@brokensoap1717 But why even want to go to the moon in this decade if it is only possible with those three systems that are expensive and which will soon be superseded by Starship based solutions anyway?
Why spend a lot of further money on SLS+Gateway (only Orion development is already finished) when we know with high certainty that these systems will be outdated in 10 years?
And note that Starship could be used much earlier as a replacement for SLS/Orion/Gateway if we initially don't use Starship for launching and returning humans from/to Earth. I think we could launch and return them using the Crew Dragon or Starliner spacecrafts where they switch to/from Starship in LEO. At least I know no argument why this would not work.
I think this solution would only take marginally more time than the current Artemis which uses both SLS/Orion/Gateway and Starship. And it would be much cheaper.
9:00 (table of orbit options) the occultation thing seems a bit overblown. Can't one place a satellite or two in orbits to relay communication? Other than that the NRO seems pretty decent. 0.5 day journey to the moon vs. some of the other orbits with up to 3-4 days seems to be its major trump rel. to the other orbits with "feasible access from Earth with Orion", whatever that means. Is DeltaV the limitation there?
Yes (for various reasons including history, cost, etc.), and regarding relays they are expensive and complex (at least compared to no relays), making them hard to justify when a relatively easy to reach orbit eliminates the need for them.
@@emilybraswell4570 If we are aiming for a permanent presence on the moon, satellites seem a pretty desirable component. Also, the Chinese have their magpie. Surely we could manage one. even commercial entities are venturing to send missions to the moon, and compared to the total cost of Artemis I really don't see a satellite or two as a hefty financial consideration.
@@FredPlanatia Perhaps, but this means a satellite is not *required*, and if said satellites go down for some reason you still have Gateway. That said, I do believe at least one lunar satellite constellation is planned (albeit not by NASA).
Is more time above Shackleton crater to observe really more useful than passing over at a low altitude?
What software package is this? Great work Scott!
Interesting. solving the three bodies problem has yielded some fascinating results. If we apply some of those 'halo' rectilinear orbit zones to the Sirius system as high probability zones for finding if Sirius C actually exists ( and helps explain the eccentricity of the system ) , then perhaps the James Web telescope could used to efficient extent for that purpose
Can't sleep so trying to watch this but I'm so tired 😴 it's not going on so I'll have to rewatch tomorrow, cheers Scott mate 👍
I looked up "rectilinear" in the dictionary during an earlier video. It didn't help much. Thanks for this video! 👍
Great break down scott
Great analysis. Thank you! Testing and "Proof of concept" is always a good idea!
great video! Thanks for explaining this to us all
just so everyone knows, "near rectilinear halo orbit" is when the orbiting object is orbiting the PLANET and making near passes with another orbiting body.
basically, while you can think of it as orbiting the moon as an oblong orbit with a really big apoapsis, you can also think of it as an orbit around the earth that is also being affected by the gravity of the moon, actually you should think of it as the latter because that's what it is, regular orbits around the moon aren't tidally locked to earth and i'll explain:
it's not just a standard orbit around the moon, it's using earths gravity to remain tidally locked and the moons gravity to raise and lower itself along the ridges.
CAPSTONE is using a Ballistic Lunar Transfer, id love to see you go over that. It seems like a very intresting low energy transfer. Thanks for the video!
Hi Scott! Another Goodie! Have you soloed? Could you let us know? An update on your flight training would be very exciting. Anyhow, great stuff!
When the lunar gateway is on the close approach and on the turn around the North Pole of the moon would they experience a Centripetal force much like a car going around a turn where they would be feeling a forced against the walls of the lunar gateway? If anybody can answer this I would appreciate it. Great video!
My intuition says no but I’m interested in hearing the scientific explanation
No, they will feel no 'gravity' or sense of acceleration even when buzzing the north pole. The astronauts and their space station would, given the same starting position and velocity, independently follow the exact same path through space. Gravity Independently acts on the astronauts and the space station to make them follow an orbit, so there is no 'cornering force' like one would feel going around a corner in a car. Conversely in a car the force that the car exerts on you is the only reason you Follow it around the corner instead of continuing in a straight line.
both astronauts and surranding them station will be in "free-fall" - situation where external gravitational forces are not countered by any reaction (exactly as in the case of people in ISS). In fact, what we commonly desribe as expirience of "eart gravtiation" is in fact expiriencig reaction force (puted on our feets).
He he he. You nearly said Rectum?
Damn near killed em..
Is there any chance the gateway might be able to get a glimpse of webb? obviously not close enough to see it clearly but might get a glimpse of the sunsheild reflecting?
Thank you for sharing Scott
So, when it's completed and on orbit, will Gateway be bright enough to be visible from Earth to the naked eye?
So when a rocket launches from earth to rendezvous with the lunar orbit, is it going to be aiming to meet at the point of lowest angular velocity around the mun (apogee)?