NASA's New Exoplanet Hunter is Using A Clever Orbit

The Transiting Exoplanet Survey Satellite (TESS) is launching on board a SpaceX Falcon 9 rocket, and some clever work by the designers has enabled it to reach an ideal orbit with almost no work by the spacecraft. Instead much of the work is carried out by the Falcon 9 upper stage with only small adjustments made by the spacecraft's attitude control thrusters. By doing this they were able to make the spacecraft even cheaper and fit it into the small budget available.

[@RMoribayashi]

The Lagrange points get all the hype but this is some seriously impressive orbital mechanics.

[@rtaraquin]

Looks like an orbit I accidentally get in Kerbal all the time.

[@mekkler]

Me too, but to do it on purpose. That's where the genius is.

[@enoughofyourkoicarp]

Fooling people into believing it's intentional? Priceless.

[@JohnMichaelson]

A Kerbal orbit is never accidental. It ends up at the inclination and eccentricity precisely as it intended to.

[@Drixel5]

RAVA Corey LoL

[@petlahk4119]

John Michaelson, you gotta site things properly. "A Kerbal orbit is never accidental. It ends up at the inclination and eccentricity precisely as it intended to." - Kandalf the Green

[@RamHomier]

They better F5 when they get close to the moon cause these things are finicky.

[@boahneelassmal]

and better check 'dem stagin'!

[@alexlandherr]

bruchpilot747 It’s “Check Yo’ Staging!”

[@boahneelassmal]

yes, because SpaceX / NASA is just one person. m[

[@willis936]

I hope their simulation step size is sufficiently small or else this puppy might be leaving the solar system at the speed of light.

[@petlahk4119]

willis936 - NASA: "Did you run the simulations?" Elon Musk: "Well. I mocked it up in RSS KSP. So, I think it'll work." NASA: *Facepalms and frantically double checks all the math*.

[@Eltaurus]

4:55 The integer period relative to the Moon is not a Kozai resonance, it is a mean motion resonance (MMR). Kozai resonance is the libration of argument of pericenter, coupled with the libration of eccentricity and inclination. Kozai resonance does not necessarily require MMR (it was first discovered for non mean motion resonant orbits, actually), while MMR does not always lead to Kozai resonance. And the high inclination you are talking about is required only for Kozai resonance without MMR. In case of MMR, Kozai resonances can occur for small inclinations as well.

[@crackedemerald4930]

i thought he was saying quasi

[@ceonikhilpande]

This is why I love Scott Manley. I literally learn something new every video I click. You are my favourite space KZbinr atm, right after PBS Space Time and SciShow Space

[@unvergebeneid]

Nikhil Pande, _after_ Scishow Space? Their research can be really sloppy and Scott's understanding of the subject matter is _much_ deeper than that of the guys at Scishow. PBS Space Time is the bomb though!

[@patbak235]

sci show is garbage

[@SeanFalloy]

Cool! I am much more excited about this mission than I was 7 minutes ago.

[@redwoodrivers]

Thanks for giving me new levels of appreciation for what these launches are all about.

[@Tomwesstein]

The Mindful Nomad , I could not have found better words! I feel exactly as you say

[@Nojaru]

SpaceX shoulda used the procedural fairings mod

[@johnburr9463]

I had heard there was something special about the orbit and was curious. Thanks for the timely info.

[@mostrosticator]

I always want to play Kerbal Space Program when ever I watch Scott.

[@Tfin]

I'm waiting for the contract completion bug to be fixed, as it's rather annoying. The landing gear fix... is also a thing I want.

[@travcollier]

Sadly, N-body physics and normal KSP gameplay doesn't really make sense. However, now I really want to do some sandbox missions with the Principia mod.

[@ekzact92]

Do it! I've currently got a Principia career going with a few custom contract packs, and its been fantastic. It takes a bit to get a feel for the N-body orbital dynamics, and a learning curve for docking, but its so much more satisfying. Also Principia's built in mission planner is in some ways far better than stock.

[@mekkler]

Go for it! The only way it can go wrong is the exploding.

[@sixstringedthing]

I always want to play Kerbal Space Program. :)

[@frosto7]

Interesting fact: The F9 second stage will be going much farther than TESS. It will be disposed of on an hyperbolic escape trajectory to a heliocentric orbit. They will need to separate TESS soon-ish after reaching the transfer orbit and then do a small extra firing to accelerate the stage to escape velocity. Surprisingly little extra propellant will be needed for this, since the required delta-V for escape from this high-energy orbit is small and the stage will be light.

[@scottmanley]

I didn't realize that, otherwise I'd have mentioned that in the video.

[@nathanaelvetters2684]

Yeah with an apogee that high it doesn't take much to escape

[@wwoods66]

Huh, so SpaceX's second mission beyond Earth orbit?

[@MatthijsvanDuin]

Why not make it burn up in earth's atmosphere instead? Its orbit would already have taken it very close to earth again so not much correction would have been needed to make it deorbit instead, right?

[@frosto7]

+Matthijs van Duin : The deorbit burn would have to be done at apogee to not need even more propellant. The upper stage operational lifetime is too short for the long trek to apogee. Even if you added extra batteries like for the FH-demo upper stage, the US have not been tested in the thermal conditions it would face when spending such a long time so far from earth as on the trip to that super-high apogee, and SpaceX has probably not developed countermeasures to avoid the RP-1 freezing solid or done all the extensive qualification work to be sure all the parts can work properly under those conditions.

[@lateniteriot13]

I am so glad I subbed to this channel a couple years ago. As always another very informative video, thank you Scott for giving us a little bit more knowledge in our day.

[@Diani4629]

Great video, didn't know about the orbit thing.Thanks for the info.

[@nolanjshettle]

"exploder class" that's a ballsy name right there...

[@foobarbecue]

Scott, please never change the way you say "explorer."

[@exoplanets]

*can't wait for the launch!*

[@Lepo4256]

Wait no more! hahah Yay!

[@Papershields001]

Very cool. Ever since I watched LADEE launch on that tiny rocket from Chincoteague and make it to the moon high efficiency orbital tricks like this have fascinated me.

[@willbkr867]

LESS POWER MORE EFFICIENCY AND CHECK YO STAGING👍🏻👍🏻👍🏻

[@FifthSplit]

*MOAR BOOSTERS!

[@doorhanger9317]

*CHECK YO ASPARAGUS STAGING

[@mhilmyfauzi4523]

I'm already excited for this mission because it has "Exoplanet" in the name, now I'm even more excited because of the orbit.

[@freedomis4all]

Cool interim while waiting for the second engine second start. Thanks!

[@lupo19fun]

Thanks for the updates!I love all this "Space Activity"!!

[@dork18777]

Thanks for breakdown. I had heard about the orbit being something out of the ordinary and this explained it much better. Thank you!

[@suretobringskills]

Your habit of using "apoapsis" shows your familiarity planetary orbits. Something we said regularly in addition to periapsis regarding Pioneer 12 at NASA Ames Mission Control. It will always be the right term if you forget which body is being orbited. Using the gravity assist of the Moon was brilliant!

[@harryganz1]

I hope this mission goes well as that final orbit is a thing of beauty.

[@densealloy]

IMO one of your best videos, Scott. I am a space wanna be nerd but, I am flat out too damn dumb and a lot of the time your vids, while they do a good job explaining the science or maths, I have to watch several times and do additional research simply because I don't have the foundation. It's good that I have to do this as I do recognize the knowledge gained. But with this one the info and graphics plus the explanation of the cost benefits just really had me nodding along in agreement. Thank you for helping to fill in the chasm in my U.S. public education.

[@ann_onn]

Thanks for explaining it -I was reading about TESS, and wondering about the challenging orbit, when your new video popped up!

I feel so dumb watching this kind of video. Simple amazing how precise this complex systems are. Thank you so much for breaking this down for us. Kudos for the team and you!

[@rolfw2336]

Wow, that orbit is really cool. Thanks for explaining it!

[@nilsp9426]

And this is why one good idea can be worth millions of dollars... the power of design! Love it!

[@ChristopherDoll]

Love that faring. I'd be embarrassed if I did that in Kerbal Space Program.

[@ColinPaddock]

OTS FTW!

[@Rain663]

That is impressively clever. Gravity assists are just so magical. Well explained

[@VikingTeddy]

Thank you for this. A very easy to understand explanation. Top be fair, you have a very soothing voice. You could read a phonebook to me.

[@TarisRedwing]

Nice shirt.

[@rinoz47]

I hope nobody needs this anymore....

[@austinhamilton9707]

I had forgotten that Scott was a TLD player. I'd love to see some gameplay videos from him.

[@sambenedict7804]

I am the worst at TLD but hey, I still have fun.

[@wp2746]

Good choice

[@sciencecompliance235]

Hi Scott, I think the word or phrase you’re looking for at 5:50 may be simply “Orbit Design”. This is basically the title of Chapter 7 (also includes constellation design for multiple spacecraft networks) in “Space Mission Analysis and Design” (SMAD), Third Edition.

[@wbwarren57]

Great analysis! I don’t think anybody else gets into this amount of detail.

[@Happyhurtzlikn]

Thanks to KSP and your great videos about ksp, I understood a lot more than I should have ;)

[@davidrobine5350]

Great explanation, as always, Scott! Thanks.

[@dwadl]

great video. it's remarkable how much i understand about the terminology just from playing KSP

[@lovt16]

The $200 million budget is for the satellite alone. Launch costs are tacked on after

[@scottmanley]

Yeah, I misremembered. But the aim is still to make the rocket do as much work as possible.

[@lovt16]

Scott Manley yep, cool stuff!

[@skyhawksp]

Really interesting! I'm excited to see how it progresses

[@BestJohnEver]

Peace of cake! I do it all the time in KSP! Hahahahaaa! Thanks for the news Scott! Always is nice to see your videos.

[@ryanvoll7088]

Thank you for letting me know about this launch today. I'll keep my eyes open for when SpaceX goes live.

[@_Andrew2002]

Roughly two hours from now, and it's a drone ship landing and will hopefully be resued on the next ISS mission,

[@_Andrew2002]

Nevermind it's being scrubbed till Wednesday 18th

[@OldGamerNoob]

I'm noticing on the rendering of how it takes turns surveying different parts of the sky, that it covers two particular patches of sky for much more time and much more consistently as it is where each of it's survey paths overlap (on what would look like the "poles" of it's rotationary axis) I wonder where they chose to position these patches of sky. I sure hope it is in places of high star density so we can get lots of good data from them.

[@happyhome41]

I'm just catching up. This is amazing insight. THANK YOU !

[@jefffradsham2297]

developing that orbit is a fine piece of orbital engineering!

[@Maadhawk]

It is a brilliant piece of Orbital Mechanics Planning.

[@tixeright9120]

Ive done this kind of thing in kerbal space program before. Seems to work well enough when you have under powered engines for your fuel/payload size. But I don't know, on KSP it probably only saves 300 dv or so & it only seems really useful if your destination literally out in the middle of no where, which apparently is the destination of the TESS satellite. What's really fun is when both moons are in alignment on Kerbin, so you can do a direct to Mun burn from launch, and then a gravity burn to Minmus from the Mun, and then a Minmus shot practically anywhere in the kerbolsphere you need to get even when those alignments aren't working out so good for a traditional course. Typically you want your Mun gravity shot to be most of the velocity burn, with minmus providing the proper alignment-course correction burn. For me, saving fuel using these gravity shots is the best way to intercept that weird DRES planet that practically has no gravity, that is like a parody of Ceres, b/c I typically need a lot of delta to slowdown once I get an thread-the-needle kind of intercept. Every other destination, I typically just want to h-transfer wherever I'm going b/c I'd rather be lazy than ballsy.

[@DavidOwensuk]

Thank you Scott - great explanation !😁👍

[@SciSky]

TESS should be an exciting step as we get ready for JWST. Hopefully TESS can find some exciting exoplanets that have the potential to harbor life! Then JWST can really hone in on the best ones. Great video! I didn't know about the unique orbit until I watched this!

[@MrJdsenior]

Great vid, not something that would have come easily to mind as a mission savings tool. This stuff is obvious for planetary travel, but using the grav assist from the moon to increase deltaV, delta inclination, and orbit stabilization wrt moon periodicity is good stuff.

[@outlawis1337]

@Scott Manley I really hoped you make a video about TESS's orbit! And here you go! I can count on you. Fantastic! :D

[@muzakmike]

Would love to see a follow up video and see how they did!

[@Veptis]

I love to know about more interesting orbits that actually get used, the cycler was really interesting. Maybe something about comets and missions to near earth astroids? So in 61 days TESs will reach science operation and we hope to find out, that our solar system isn't as special as some thought due to biased in knowing more hot Jupiter though Kepler. What are the expected achievements here? Finding more and more rock lick exoplanets and learning about solar systems and planet formation? Finding system within our reach or an interstellar probe?

[@hopp2184]

MrVipitis I believe the ultimate goal is to find evidence of life if there exists any. The rest is of course important however finding life would be extraordinary

[@Veptis]

Ahsoka Tano I think the biggest step we will do towards this is JWST if it goes operational by 2023 or something....

[@danielcollins4172]

Don't forget, Planet X is still out there somewhere...

[@Vulcano7965]

As Scott said, it probably will only detect objects with a short orbital time. So we will still get more Hot Jupiters, but from the whole Galaxy. There is also CHEOPS from ESA that will continue to examine already known Exoplanets.

[@Tfin]

They won't find a system within reach of an interstellar probe. :)

[@jimcole5359]

This satellite should give us some impressive imaging without getting much interference due to the orbit. I do love how you slipped into KSP talk when you first mention the apogee by using kerbal terms :-)

[@patrickt4488]

Holy crap, something actually brilliant and innovative from NASA. I haven't seen that in a while.

[@HoRiGa94]

Thats actually a pretty neat orbit they have there for basically uninterrupted oberservation. I wonder how that compares to sending JWST or so to L2?

[@jeckobandit69]

Very interesting. Thanks Scott

[@R.Instro]

If using the applied knowledge of scientific processes to produce a desired set of works qualifies as "engineering," then the fitting of TESS' orbit to its mission goals viz. the available hardware, resources & safety concerns is probably best labeled as such. No need to make up or hunt down new terms when a perfectly good one already applies. =)

[@TheFLOW1978]

I've been asking this myself over the last couple of days. Thank you for that.

[@FTBLN]

Very informative, thank you. Subscribed instantly.

[@captaincharlie3105]

Thanks this really cleared up the mission for me 👍🏻

[@AlexKnauth]

How exactly do they get a gravity assist that will incline the orbit? Do they aim for a spot just "north" or "south" of the moon? And then how do they shift the phase of the orbit so that it never goes near the moon again? If they end up in an orbit with a small integer ratio with the moon that also started at the moon, they'll go near the moon again pretty soon. So do they wait a couple orbits with a different ratio before turning into that small-integer-ratio orbit?

[@scottmanley]

The post lunar gravity assist orbit returns it to perigee after 3 weeks, then it changes the orbit to a 2 week period, that's how it gets into a 2:1 resonance with the right phase.

[@joshuasims5421]

And yes, if you come in at the moon with some relative inclination, then your gravity assist can set you on a highly inclined orbit. OSIRIS-REx did something similar to catch up to Bennu. So aiming a little north or south of the moon is essentially what they're doing.

[@scottmanley]

Actually, Parker Solar Probe is going to use gravity assists that will arrive at the place where Venus will be, because they want to reduce orbital energy.

[@CombraStudios]

It looks like you never played KSP, Alex

[@JamesAustin]

As for the inclination part, by making a small inclination adjustment relative to earth, that can translate to a high inclination on arrival at the moon. Once the gravity assist kicks the satellite way out, the new orbit keeps that high inclination that it had at the moon. You can see the whole thing happen in this video.

[@aidanwansbrough7495]

Very interesting!! That is a very clever way of getting everything to work well - I wonder how they come up with orbits like that!

[@fred_derf]

Launch is April 18, 2018, The 30-second launch window opens at 6:51 p.m. EDT

[@TheMXMach]

MRW When MechJeb does all the calculations for you. /s Great video as always, and facinating how they could exploit the gravitational forces to max performance.

[@AlaskanBallistics]

Another great video sir

[@qqq1701]

For more savings they could have put one of those wifi SD cards in the camera. When it swings by Earth it will hit the wifi and send the pics.

[@dennispremoli7950]

ahahahahahahahahaahahh

[@z5396z]

Why don't they just attach Ethernet cable to the spacecraft? Then it can send the data anytime

[@petlahk4119]

Palindromemordnilap - No no. You build a space elevator first then you attatch one ethernet cable to the space elevator and the other directly to the earth and trace the ellipse.

[@milkhbox]

petlahk You guys are forgetting about how we're going to power the probe. My vote is for cordless extension cords and surge protectors plugged into themselves.

[@MrJdsenior]

Milkbox...You can't plug surge protectors into themselves, they will produce too much energy in that configuration. Just look around on YT. I'm sure you can find this "explained" somewhere in great (albeit nonsensical) detail. Search electric universe or flat earth and you should be in the general area. ;-) Yes, I'm an electrical engineer, or at least was.

[@HappyBeezerStudios]

That is a pretty smart orbit.

[@eldencw]

Do reaction wheel induced vibrations cause any reduction in camera resolution or blurring?

[@NoPulseForRussians]

03:56 isnt that called the Oberth Effect?

[@toolkit71]

Have followed your channel since KSP was first out in early access. Love your channel and always wanted to go to space....too old now to be a pilot but with Space X that dream still might come true. The question I had was, is this a mark V falcon 9 or a mark IV? I thought they were getting rid of Mark IV? Love all the updates and different shows, all about space :)

[@philb5593]

This is a block IV. They are landing it.

[@markmcculfor6113]

I have a name where did you see that they would try to land it? I thought they were phasing out the Full Thrust variation

[@sleepib]

At 4:06 the inclination relative to the moon is really low before the gravity assist. Are they going to do a big plane change with the F9 upper stage, or is that just a mistake in the animation?

[@b43xoit]

As I understood it, that plane change comes from the interaction with the Moon.

[@sleepib]

The launch site is at a latitude of about 28.5° N. so that is the lowest inclination you can directly launch into. The animation shows the spacecraft in a much lower inclination orbit before the gravity assist, within a couple degrees of the moon itself, which has an inclination of 5°. To get into an inclination that low the spacecraft would have to make an expensive plane change maneuver before reaching the moon, just to use a gravity assist to go back to a higher inclination orbit. Just curious if the animation is wrong, or if not, what advantage is gained by the plane change in low orbit.

[@koshu4]

Is this an unusually complicated/sophisticated piece of orbital mechanics? And does explain why GNC is suddenly a concern for the launch? I know we pull this kind of stunt in KSP all time. Even as Scott is talking I can visualize the maneuver nodes in my mind's eye. And sometimes it doesn't even end up with Jeb stranded in a farside crater.

[@dennispremoli7950]

I find it astounding that we can calculate such things and execute them perfectly.

[@whereswa11y]

Excellent info Scott. Hope it all comes off. Fly nominally.

[@innsj6369]

*Norminally

[@epicspacetroll1399]

Alexandre Fyne Unless I'm missing some reference to someone saying something silly, I think nominally correct. I don't think norminally is even a word.

[@SimplySpace]

This is very clever!

[@flwi]

Wow, great explanation!

[@sigitas909]

You said something about the new satellite looking for shorter period objects, but wasn't one of Kepler's limitations that it could only see lower period objects, and we've been missing more of the jovian-type objects due to this limitation?

[@nickhull83]

fantastic explanation!

[@blah5310]

Its so cute in the faring

[@killacookbook988]

Thanks for breaking it down! Your science videos are always palpable for me. You taught a 9th grade drop out the rocket equation...and for that, I Thank You! Lol, at the NASA Press Release they played down the significance of the orbit like it was normal or run of the mill. It was either Robert Lockwood or Omar Baez that said, this isn't an orbital profile we use often, but there's nothing special about it. Maybe that was the NASA answer for the taxpaying public because I'm pretty sure Omar took the question. It seems that there is some margin of error here that could damn the mission! I mean, they probably got this, Let's hope all is good in 2, 3 days

[@eldencw]

The video was great as always! When the upperstage of F9 has released TESS, how much fuel does it have left? Is it going to deorbit via aero braking with the giant party balloon and get recovered? (Ballute is the proper name I think)

[@markpix]

Hope they checked the staging!

[@ernestwagner6842]

loving this orbit, very efficient. Gravity assists are the nitro of orbital dynamics :)

[@raybidhq]

EFFICIENCY BRO!! *high five

[@WestOfEarth]

Insightful information! I don't know any where else I'd be able to hear and understand this sort of explanation. I will add, though, an $80 million launch must have saved NASA a good chunk of money too. I also understand that TESS will only be searching stars out to about 200 light years. So while it will capture nearly the entire field of the sky, the distance will be limited.

[@dewiz9596]

Orbital Mechanics is the REAL Rocket Science!

[@motomass8458]

Fascinating, thank you.

[@bobfmirvine6652]

What a clever bunch of people!!!

[@PanduPoluan]

With TESS operational and performing as expected in its novel orbit, will we see other spacecrafts using a similar orbit?

[@guintube]

Nice Video. With all of the additional volume in the Falcon 9 shroud not being used, could they not add a small engine to help with the orbit? Engines can't be that expansive compared to the TESS itself. Also, what part does the Falcon 9 second stage play in getting TESS out to it's orbit, and when does the TESS itself start using it's own motor? Another question is that with all the volume left in the Falcon 9 Shroud, could they not have launched another payload to help offset the overall launch cost,...or is the orbit of the TESS too specialized for that to happen. Just wondering. Thanks

[@ann_onn]

I can answer one part, about the second stage burns. In fact, I'll just list the time in minutes and seconds after launch; 02:29 1st stage main engine cutoff (MECO), separation, 2nd stage engine starts 03:05 Fairing deployment 06:29 1st stage entry burn 08:17 2nd stage engine cutoff (SECO-1) 08:20 1st stage landing 40:50 2nd stage engine restarts 41:49 2nd stage engine cutoff (SECO-2) 48:42 TESS deployment

[@rosariofell735]

is there a process to cross reference the images that these different satellites send back? and also - this is not being painted as telescope. but then again any camera is a telescope. how old is the tess project? vaguely heard of ms. teresa. lol

[@brianwyters2150]

Nice shirt with "The Long Dark" on it. I saw some people play it a long time ago.

[@rh906]

Considering NASA does not seem like it wants to give up on costly rockets, I guess this is how we are going to get any science.

[@ploobooble]

4:39 looks almost exactly like my landing on the mun attempts in career with kerbals with no SAS

[@nathanaelvetters2684]

TESS launch standing down for 48 hours. 🙁

[@smarttarts]

I actually just got back in to The Long Dark after owning it for years when there was one map and it was very difficult. The game is much more balanced and fun now :D

[@chaz720]

5:50 - In my experience, the job title for this work is "Mission Systems Engineer"

[@buddyp1952]

uh, no. The MSE has to be conversant in all aspects of mission development, but the organization that does this is called the Mission Design and Navigation Branch.

[@philmaggiacomo]

Have you seen new Lost In Space? Curious as to how sound the science of the orbit of that planet is

[@ColinPaddock]

Nice shirt Scott! You going to post any Wintermute gameplay?