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

Artemis I flew beyond the Moon into a Distant Retrograde orbit, this is a special orbit which appears to orbit the moon backwards at a distance beyond the moon's lagrange points. The orbit requires low delta-V to reach and is stable over long periods, however, it regularly passes through regions where the Moon eclipses the Sun or the Earth, which is why NRHO is preferred for the Lunar Gateway.

You can get Universe Sandbox from the Humble store with this link, I make a small affiliate fee if you buy using this link

There's some great technical details in this paper

Follow me on Twitter for more updates:

I have a discord server where I regularly turn up:

If you really like what I do you can support me directly through Patreon

[Rebar_real]

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

[baomao]

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.

[donlindell]

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.

[ASpaceOstrich]

My jaw dropped at that square orbit. Thats amazing.

[jonbjo]

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."

[simontanguay]

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

[eamonstack]

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

[cal-native]

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!👍

[IanValentine]

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

[Rbobbe]

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!

[inqwit]

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

[danielmoser]

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

[charlesnazare]

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

[dannypipewrench]

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

[simba]

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

[frankgulla]

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

[MaryAnnNytowl]

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

[RCAvhstape]

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.

[jeffmartin-gr]

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

[triggerfish]

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.