What Is Distant Retrograde Orbit, And Why Is Artemis 1 Using It? 

A square orbit. Now I've seen everything! Thanks for explaining.

My jaw dropped at that square orbit. Thats amazing.

The words "Three Bodies Problem" filled me with existential dread. The trisolarians are coming.

Really nice explanation. Reminds us that orbital mechanics involving multiple bodies starts to get really complicated really quickly, esp. when you factor in other key constraints like solar panel illumination and non-LOS-comms. Nicely done.

An amazing episode. The visuals provided a whole new context for the awe inspiring majesty of moon landings, and for just a moment I was a small boy watching those brave astronauts on Dad’s b/w TV. Today’s world exceeds my wildest boyhood dreams and every episode of your show expands my universe. Thank you.

Scott, your videos are amazing. I have a family member who is an engineer. He previously worked COTS, then on developing Gateway, and now he is leading a team devolving infrastructure to maintain a permanent station on the moon. He's way, way smarter than I. If it wasn't for your videos, I would be absolutely clueless every time he talks about his job. Some times, I say something to him that prompts a raised eyebrow and the question, "How the...[heck].. do YOU know that?" My response is always, "Tim Dodd told me," or "Scott Manley told me."

I love that all these new missions are planned, I just wish the time scale wasn't so long. Basically I am selfish and want to see them in my lifetime!

Wow why has noone else properly explained this? Amazing work again Scot.

I have to admit I was feeling pretty hopeless in my comprehension until you put it into Sandbox, and then Bingo, it made sense! I guess I'm just more of a visual learner - thanks Scott!👍

Love the time-lapse!!!! Thank you.

The best part of all of this is that Scott Manley put the Hubble Space Telescope into Distant Retrograde Orbit.

It's already such a joy to hear how you say "the mün", but "I'm gonna züm in on the mün" is the best thing ever.

Scott, very clear explanation and excellent graphics - that is why the community loves you! Eamon

Keep going. I appreciate the humor in your sharing things that give my brain a little twist.

Nice job explaining and visualizing DRO, Scott! Thanks for all you do.

Scott, you explain these things so eloquently and with great visualizations.

Thank you, Scott. What a great demonstration of what these difference orbits mean and do.

Yet another great explanation! Thanks for all you do, Scott! ❤️❤️

Incredible!! Thank you Scott.👍

Scott, this is one of the best videos I've ever watched. In any category.

Great explanation for this relatively non mathematical space nut (me). Strap line: it’s a stable orbit that doesn’t take much propellant and is de-risked coz they can get Artemis back if something goes wrong. It kinda puts the huge risks of Apollo into perspective.

Pretty interesting indeed! Thanks, Scott! 😊 Stay safe there with your family! 🖖😊

Thanks Scott that was very informative

I'm surprised how honest and frank you're.

I've been hoping for a video breaking down this DRO orbit. Thanks for your knowledge Scott.

Great podcast, thank you! Keep 'em coming!

I was wondering about NRHO: it's about the lunar poles! (and LOS). really nice orbital demo and explanation! Orbit safe!

Thank you. Was hoping you would do a video on this topic.

Keep up the good work bro.

A square orbit around the moon, well I'll be! I have to say, I was one of the doubters/haters of Artemis but since the launch and seeing all this stuff lately I've gotten pretty excited about it. The odd orbital mechanics is super cool. And so, by the way, is seeing that NASA worm logo out in deep space looking back at Terra and Luna.

thanks for your content ❤

Brilliant video, Scott

To calculate this by hand must be outrageously difficult, but I guess somebody had to. Give that man a medal, he deserves it.

It's wired how much I learned from ksp. Thanks Scott

Very interesting episode Scott! Thanks I will have to view your sims on my desktop as I couldn’t quite make out the names on my phone!! 🤪 Take care!

Been looking forward to this video.

This was incredibly helpful!

Great explanation thank you!!

Thanks for the great explanation! It's so easy to forget that EVERYTHING in space is in motion and when considering the Orion's trajectory, we need to take the moon's orbit around the Earth into account too.

Every science teacher is bowing in Scott's general direction right now.

brilliant explanation 👏👏

That is brilliant, and quite elegant. From the surface of the Moon it must look like it's dancing among the stars.

Excellent Reporting 👍

It’s been a long time coming but I have to admit, SLS and Artemis are pretty darn awesome. (I honestly thought it was going to explode on the pad… but wow, it’s really delivering… just wish it wasn’t so costly)

omg this cut at 4:16. Im blind now Scott, thanks!!! LUL

The Gateway orbit is just insane. In order to make it easier to arrive and leave within certain windows, they're making an immediate abort to the station impossible unless they have the delta V to catch up, or it just happens to be that few hours orbital window when Gateway is passing over. And abort from the surface directly to earth obviously isn't possible.

Wow that square 😳 so well explained too

Can never get tired of Scott Manley saying "mun" 😊😊

I hope we still do the asteroid capture at some point.

"Distant Retrograde Orbit" is what we use to describe the short christmas visits from the in-laws

The pic in the thumbnail is one of my new favorites. Been using it on my phones home screen

I can’t imagine throwing astronauts into this thing on the first launch. Wouldn’t be prudent.

Fantastic explanation of the orbits! I would have never thought the square orbit could happen, but orbital resonance has eluded me so far. I did, many many years ago, get a rotating triangle lissajous pattern once inserting Beatles music unto the x and y drivers of an old T.V. once (just before I shocked the living shizzle out of myself.) Always love your videos.

Hullo Scott and thank you for all the great content over the years. I wasn't expecting a video from you tonight but boy I sure need the most excellent distraction.

j’aime aussi beaucoup vos vidéos, carry on 👍

NGL, that orbit at 2:00 looks like what mine would when i've messed up a mun transfer and am now trying to catch back up lol.

I love those slingshot maneuvers! We might start calling the Capstone and others the Moon Moon.

I'm hoping you'll make a video covering the successes and problems/ failures of the mission. 🙂

I had imagined a DRO to be an elliptical orbit about the earth with the same semi major axis and period as the moon but with more eccentricity. So the apogee would be a distance above the moon and the perigee would be a distance below the moon. But from the moon's POV would look like a retrograde orbit since it falls behind the moon when above it and spurts ahead of the moon when beneath. But the animation doesn't show an ellipse with earth at the focus. Looks roughly elliptical but with earth at the center. So clearly not the Keplerian orbit about the earth I had imagined. I guess the moon plays a larger role than I had imagined with DROs.

I'd be interested in a short video where you go through the back of the envelope calculation for the universe sandbox simulation.

Thanks Scott. I'm not sure if this mission is worth $2 billion dollars, but there you are... I do want to see a new Moon landing though.

Oh I see you've been stepping up the thumbnail game :D

Excellent. Well done.

super explanation 🤯

Nice presentation

TY for splaining that

I love all those really smart orbits!

Good question. I’ll watch this tomorrow but then I already done this around mun

I really enjoyed this! Thought arising by watching, (unrelated to the topic) "Could quantum computing give better access to working the three body problem?".

You sir are a student and a scholar. I’m a little slow. If you knew how important you are to me. Thank you. I am a aviation nerd. You make space approachable for me. Thank you again.

You're a natural teacher

I thought it was hilarious when the video transitioned from the solar system simulation with Artemis 1 to the white documents! It actually jump scared me!

every now and then, scott puts out a video where i go, "wtf?" this is one of those videos

Excellent presentation. Thanks Scott. Here's a few more words for the RU-vid algorithm 😁

Those were very cool CGI orbital mechanics. The real deal too.

It’s been quite frustrating not to have a good conceptual explanation of Artemis-1’s orbital maneuvers the way we got that back in the day withApollo (yes, I’m old enough to have clear memories of that), but I think I now have one (sort of), The DRO is simply a prograde orbit around the Earth that - due to the Moon’s influence on the orbit - is significantly more elliptical than is the Moon’s orbit around the Earth and is in the same plane as the Moon’s orbit around the Earth. The ends of the major axis of Artemis’s orbit lie farther away from Earth than the Moon’s orbit, and the ends of the minor axis of Artemis’s orbit lie closer to Earth than the Moon’s orbit. When Artemis is in the farther part of the orbit it orbits around the Earth slower than the Moon and “falls behind” the Moon. When Artemis in the nearer part of the orbit it orbits around the Earth faster than the Moon and thus “catches up and passes” the Moon. Viewed from the Moon this would look like a retrograde orbit around the Moon at a great distance (if the distance wasn’t large, the Moon’s gravity would dominate and Artemis would orbit around it rather than around the Earth). The Outbound Powered Flyby and Return Powered Flyby are just lunar gravity assists - helped along by Artemis OMS burns - to get Artemis on its way to DRO and get it on its way back to Earth. What I would like to know is if the Outbound Powered Flyby and Return Powered Flyby burns are retrograde or prograde burns, and the same for the DRO insertion and DRO departure burns (I assume the DRO departure at least must be a retrograde burn).

Seeing that squarish tail is truly amazing

I hope you'll put the Hubble Space Telescope back once you've finished with it.

This will be used for other planets, moons and satellites as well !

Love the way you "spitballed" an orbit stable for 13+ years. Class.

At long last, NASA has proven that it's hip to be square.

It's pretty cool to see that now we are advanced enough in orbital navigation for these trajectories. Big advancement from the 2 body approximation and directly flying to Low Lunar Orbit that Apollo used.

Well done for finding an almost square orbit. I think I'd call that one a 'toast orbit' because its shape resembled a slice of bread more than a square, with some concave sides and one convex one like the top of the toast that doesn't get toasted if the bread is too tall for the toaster. It was great to see an eclipse of the Earth from Artemis as well - not quite the same size though. I wonder has any probe/satellite managed to film the moon eclipsing the Earth when they are exactly the same size? Or has one at or near the Earth's L2 point found the point where the Earth can eclipse the sun appearing the same size? It must happen somewhere.

Although fairly controversial, the advantage of Artemis is all the cheese from mining the Moon.

0:22 This shot is so much like that famous stage separation from the Apollo era (mind you, AS-202, it was a Saturn IB, not a Saturn V)

“Pen to envelope” 😂 My favorite way to take random notes, too!

A square 'orbit.' Absolutely fascinating!!!

@scottmanley, do you think you can see Artemis I's re-entry from the CA coast? Or how far inland do you think one can see it from?

Thanks for the nice conspectus of this flight profile. It's odd, but Artemis is an odd program for odd times.

Hi Scott!

Scott, the go to guy to explain this stuff to regular people

shout out to universe sandbox!

Great explanation. I also wanted to see that asteroid redirect mission happen. Oh well, the landing on the moon will pave the path to Mars so.

last time i was this early Scott still had hair :P

thank you

I don't understand many of the words used here. But I really like the space bird eye view where Artemis 1 literally just uses the moon to kill all it's orbital velocity and just drops to earth.

4:16 think fast, chuckle nuts!

Fascinating and mind boggling. But to put it in perspective, the averGE 1990 Hyundai had more computer power than the first lunar lander. Much of the Apollo Mission was done on a slide rule.

that is so efficient its unreal

Thank you for making this video, I've been wondering about this ever since the launch!