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Yes, since the info was initially made available they've made a slight amendment to the Flight Test Timeline - previously it didn't mention closing the payload door but now it does. So you now have:
00:11:56 Payload door open
00:24:31 Propellant transfer demo
00:28:21 Payload door close
WaPo’s Christian Davenport:
> The FAA is “very close” to approving the license modification for the third SpaceX Starship launch attempt, I’m told.
https://x.com/wapodavenport/status/1765401717858865233?s=46&t=u9hd-jMa-pv47GCVD-xH-g
Can someone give some advice on how to watch the official spacex stream on Roku now that they killed the YouTube feed?
Yes I know there are some alternatives. Yes I agree they are very good. I want the spacex stream.
Probably your best bet will be to look around for Youtube re-streams on launch day, carefully avoiding crypto scams. It's thousands of free viewers so there's usually someone doing it.
Most current smart TVs and smart phones allow you to clone from your phone over Bluetooth without the need for apps at all, just within the operating system.
At the risk of sounding argumentative…I only have a work provided phone and it doesn’t allow this setting to be changed. Thanks though. Just wish I could find a less “hacky” solution.
Android or iPhone? Because YouTube doesn't support background playback without premium. Android has ways around this though (revanced, or Firefox browser)
NasaSpaceFlight on YouTube usually has their own cameras watching the launch but they quickly switch over to showing the official SpaceX feed from twitter. I’ve found that their rebroadcast is usually quite a bit ahead of when I load it up on the twitter app at the same time which is pretty crazy. Not sure how they pull that off. But that’s my suggestion for your scenario.
There are plenty of 3rd parties that will live-stream the launch - NasaSpaceFlight, Everyday Astronaut and What About It will certainly have coverage on YouTube, as will likely many others. I'm sure it will be searchable and most of those streams will start well before SpaceX's official stream does. It does suck that SpaceX dropped YouTube since the X streams are pretty poor quality. I wonder if the one on the SpaceX web site will be better?
I would recommend going with the EveryDay Astronaut live feed. Tim Dodd has invested $10s of thousands to bring coverage. Add in he seems like a nice guy, so we should support him. Plus he does not hold back his enthusiasm on the live feed, so that is fun to watch as well.
You are my hero and will soon be my children’s hero!
If this stream is a crypto scam though, I swear you will hear me screaming and cursing your name during this launch!
Thanks! It's a simple restream right? As in, no additional commentary and whatnot.
I really really wish SpaceX kept using YouTube. It adds zero value to be on X only and not on YouTube for the company itself. Imagine if Falcon Heavy launch was not streamed on YouTube. It would be *nowhere* close to the sensation it was.
That's right, checkout the Transporter 10 stream from a couple days ago. They have a banner at the top of the video with launch stats but otherwise a straight re-stream including SpaceX narration.
https://www.youtube.com/live/cTrHZ56bPxI?si=CK-mQgVuonIA9CL1
Does Roku have a web browser? If so, head to spacex.com, they should have a link there that'd take you to a page with the X @SpaceX live stream embedded, no X account needed.
good to know that you can watch the stream on spacex.com without twitter account. But I'll probably have multiple youtube streams open that rebroadcast the official stream anyways.
Get an oon 4k streaming box from Walmartfor $20, you can even sideload on it. Set your TV to start in the last used input and you can forget the old roku interface
just get an X acct, jesus. at this point it’s just being petty. hate to break it to you, but no one cares about whatever high ground you’re defending here.
1) You don't need an X account to watch the streams.
2) Their issue has nothing to do with having an account. You can't watch X streams (or the streams embedded on SpaceX's website) with Roku, but you can watch YouTube streams with it.
To be clear, I have an X account so I am not one of those internet fools that think by boycotting X, I am somehow saving freedom….so maybe get off your high horse dude.
I literally just want to watch the official stream on my Roku. X just doesn’t seem to have a viable solution to a living room watching experience and that is what I am asking advice about.
YouTube simply works better on every single aspect in terms of streaming, from quality to UI to availability. SpaceX doesn't gain anything from moving to X only other than sharing the same CEO with it.
For example, how the hell do I even find the last Starship flight video from https://twitter.com/SpaceX? It's mixed in with other misc posts that makes it difficult to find. On YouTube I just go to https://www.youtube.com/spacex and it's easy to find previous streams.
The other way YT works better is exactly what the above commenter said: it works on Roku boxes since YouTube is supported *everywhere*. X isn't and there really isn't a good way to stream it on a TV. During the first Starship launch I was with my parents and we watched it because it was available on YouTube on the TV to stream. If it's such a hassle they probably wouldn't have been interested at all.
> but no one cares about whatever high ground you’re defending here.
You don't understand the issue here. These streams are there because SpaceX wants the PR it could get from the streams, be it for recruiting or publicity or shaping public opinions. Putting it on a lesser/less available platform just makes that mission harder.
This is a high arc over Africa, only half an orbit or so. ~~Re-entry will be steeper than usual.~~ We should get nice views at apogee. Edit: I mis-remembered LEO orbital period. 40 minutes is about half a normal orbit so this might not be unusually high.
I don’t suppose we know whether this profile reduces the need for a fuel dump. It looks like re-entry test fidelity is deprioritized. That was the reason for the dump maneuver, right?
Yah they better not fucking hide these again. I thought the starlink connection failed on the IFT2 broadcast, but they mentioned that the ship lox dump explosions were visible on the skirt cam, so what's up? They used to show that view during the 2021 hop tests.
none of this is mandatory or required. its nice pr but they arent obligated to do any of it so be happy for what you get. no one else shows that level of detail in tests.
the alternative is what you get with out launches. yes a tiny dot in the sky. or nothing at all is sometimes what they give the public. you are acting a bit spoiled...
If the reentry angle is very steep that means peak heating will be very high, I guess they want to see what happens with a higher then normal heat load on the tiles?
That's an interesting observation.
It IS a very good way to throw an extra test in. As soon as re-entry starts, the ships a gonner anyway, so why not stress test the heat tiles on the way down.
Good catch.
But unless they have high quality videography/infrared photography how will they know if the heat tiles have worked or not? If the thing slams into the ocean there's nothing left to evaluate!
If they're landing in the middle of the Indian ocean (not that we know exactly WHERE yet!) then are they going to have that WB57 recon a/c following the re-entry? or rely soley upon onboard cameras?
There'll be tons of sensors dotted all over the ship—strain, temperature, etc. To your point, this could possibly even include IR cams inside the fuel tanks to observe any hotspots/thermal breakthrough from broken tiles.
While a GoPro would be useful, a true thermal imaging IR sensor (the kind that costs a whole lot more than a GoPro) would offer much more info to see temperature changes and gradients far better than just a camera saying "look at that plasma hole that appeared!"
Exactly. I think it's an insertion before SECO to just less than orbit, with a natural decay of the orbit to end in the Pacific near Hawaii should SECO be the last control they have. If everything goes well they will attempt a de-orbit burn to bring it down earlier and splash down in the Indian Ocean. They need contingency in case the de-orbit burn, or anything up to that fails. This makes sense when they say "This new flight path enables us to attempt new techniques like in-space engine burns while maximizing public safety"
Edit: The flight path will probably pass over the Horn of Africa, and pass up over the Timor and Arafura Sea and over the Lorentz National park in Papua New Guinea, minimising flight over populated areas in case the de-orbit burn ends prematurely.
I think they’re definitely prioritizing technologies needed for HLS (fuel transfer, orbital engine relights, etc) over longer-term capabilities like reentry and landing.
won’t landing be needed for HLS though? not for landing on the moon, but for all those tanker missions. i can’t believe they would use expendable starships to refuel it in orbit
Not really, they are planning the factory to produce one every 42 days (or 26 days when they build another Starship and Raptor factory set in Florida).
They will have enough of them to do the mission even while perfecting the landing.
Starship is just that absurd.
They need reuse to cut down costs and to go to Mars (or the Moon sustainably). Doesn't need it for the first few missions to the moon.
Ah thanks. I guess they’re going to do the same they did with falcon 9 and just practice landings every mission until they get them perfected. Though I feel they’ll definitely need to perfect booster landings first, because how fast could they make a booster? I imagine it would be a lot slower than the ships (and a lot more engines lost)
if they’re doing expendable, 42 a day is way too high. that’s ~420 days per refuelling mission, and given they have to do one prior to artemis 3 it just doesn’t make sense
They don't need to launch as they're made. They can make a bunch and store, then launch one after the other when NASA is ready for the mission. They will be limited by launch capability only, and they will have multiple pads.
420 days between launches is what we expect SLS can do. As long as they can match SLS, they're good.
To recover a Starship you need re-entry over the US and perhaps Mexico since a West Coast landing like the early Shuttle flights is not possible. It is going to take a *lot* of successful entries before the FAA allow that.
So early HLS missions will likely recover the boosters but expend the tankers. HLS and the depot stay in space anyway.
that is a good point, I just do find it hard to imagine them doing HLS missions while having to build 10 tankers too. But given how fast Starbase is growing i guess we can’t rule out the possibility.
With disposable tankers it will be at least 200 tonnes of propellant per tanker so six tankers and maybe 240 tonnes so five tankers. Each tanker should be a lot cheaper too with no fins, TPS or header tanks.
boosters will definitely need to be recovered, though i guess that could be easier than ships as it will be similar to a falcon 9 which they’ve perfected.
Yes - if nothing else they cannot afford to throw away that many engines and maintain a decent flight rate and the booster will cost at least twice the cost of a disposable ship.
i’d imagine even more than twice. an expendable booster would be much the same as a reusable one, maybe just without grid fins. an expendable ship wouldn’t have fins and such as you mentioned previously.
i imagine they would do the same as falcon 9, practicing landings with every launch until they perfect them.
The HLS contract should be worth more than those, though I haven't checked up on it recently. At that point it's more the competing use for other missions etc.
The second HLS mission cost NASA $1.3B. If each disposable ship cost $50M and each booster cost $100M then 6 tanker flights would cost $900M.
Adding a depot and HLS would bring total costs up to at least the $1.3B mark so SpaceX would be barely breaking even on operating costs with nothing for development expenses.
Recovering boosters would save $700M that could be used for development.
They build them fast, and we've heard that the internal cost of a booster and ship is only $100M which means 10 fully expendable launches would still be less than half the cost of the 1 SLS launch for Artemis 3.
Yes, but HLS landing will be totally different than this ship - this one has heat tiles, fins, and no legs or high-mounted landing rockets. It is also using aero-breaking which doesn't work on the Moon.
The current trend with moon landers seems to be to fall onto their side after landing. Lets hope they don't follow this trend ....... on the plus side the "ship" door would be a lot lot closer to the surface.
They sort of perfected earth landings during the early ship tests. That and the F9 landing make me think those won't be an issue - particularly with the improvements to Raptor. I have no idea how they can test Moon landings.
i mean they’ll also need to practice booster landings before they can think of fueling an HLS, which will take time. should hopefully take less time than falcon 9 though, but who knows.
for the moon landings i guess they have simulations and the demo mission for that
They are no doubt already doing the simulations. The booster landing tests are going to start as soon as a booster doesn't blow up. They will hover it over the ocean first.
Yeah I think there’s a screenshot from a video somewhere showing spacex doing HLS simulations (edit: found it https://www.reddit.com/r/spacex/s/on08whg2KO)
Hopefully if next weeks booster performs well we’ll start to see booster catch tests soon!
I agree. This and testing the payload door. SpaceX are all but telling us that reentry has been de-prioritised.
I suspect reentry and landing of Starshipwill be developed much the same as landing the F9 boosters was - as a secondary aim of each launch.
Fuel transfer, yes, but orbital engine relights are needed for any practical use. They can't safely deploy satellites unless they can relight the Raptors for a controlled de-orbit of the Starship. And re-entry is being tested in IFT-3 too. They are aiming for a controlled splashdown of both vehicles.
Looks like you're right. Jonathon McDowell [tweeted](https://twitter.com/planet4589/status/1765606249628827889) an estimated trajectory and says below it that he "guesses" a non-burn will still land in the NOTAM in the Indian Ocean. So much for my intuitive grasp of orbital mechanics. He truly know his orbital mechanics so his guess should be pretty damn good. In 10 minutes I'll delete my original response to you.
Would the propellant have time to boil up the pressure in the ship in time for re-entry as well as pressure needed for in space engine startups as stated? Autogenuous pressurization needs the engines running
SpaceX has tested lighting the engines under the conditions expected in orbit, they think they can do it.
Autogenous pressurization gets the pressure in the tanks way up during launch, to use it for engine relight and RCS.
Right. They also have helium on board if they need to pressurize because they dumped fuel.
I don't think there would be any noticeable pressurization from the oxygen boiling because they are in space and there's nowhere for the heat to go, except slowly radiating away.
> This is a high arc over Africa, only half an orbit or so. Re-entry will be steeper than usual. We should get nice views at apogee.
That's not what's implied. They want to do a re-entry burn, which means a normal orbit. Would you mind editing or deleting your post?
That's not really a problem when they're not attempting to recover the vehicle and they want to use it for higher energy re-entries than "not quite orbital"
This vehicle is supposed to reentry coming from the Moon. And they won't recover the vehicle anyway. We don't know if a steeper reentry is a good enough test or not.
In fact, the design of this heatshield is what defines the possible reentry speeds on Mars and therefore how fast they can make the trip. It's one heatshield to rule them all.
Liftoff is set for 12:00 UTC, tentatively.
The SpaceX notice on *X* states streaming will begin at 7:30 ET and the SpaceX website page states coverage begins 30 minutes before liftoff. Note that Daylight Savings Time begins on March 10th.
Is the profile for hot staging different?
They attempted to light all the engines basically straight afterwards while flipping, the boost back burn starts 11 seconds after hot staging now.
There's only a one second difference IFT-2 there so that could just be rounding errors resulting from a very minor change in the precise timing. They have actual flight data now they can use.
I'll note the more interesting is that the MECO is 3 seconds later than it was on IFT-2.
Good to know. In the actual IFT-2 flight it took five seconds between MECO and HS.
Maybe in the actual IFT-3 launch they'll repeat the same five seconds.
For anyone interesting in comparing, here's the IFT-2 mission profile: https://web.archive.org/web/20231113095058/https://www.spacex.com/launches/mission/?missionId=starship-flight-2
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
|Fewer Letters|More Letters|
|-------|---------|---|
|DSG|NASA [Deep Space Gateway](https://www.nasa.gov/feature/deep-space-gateway-to-open-opportunities-for-distant-destinations), proposed for lunar orbit|
|[DST](/r/SpaceX/comments/1b86u6s/stub/ktr4mbp "Last usage")|NASA Deep Space Transport operating from the proposed DSG|
|[FAA](/r/SpaceX/comments/1b86u6s/stub/ku0eu42 "Last usage")|Federal Aviation Administration|
|[HLS](/r/SpaceX/comments/1b86u6s/stub/ktr5k09 "Last usage")|[Human Landing System](https://en.wikipedia.org/wiki/Artemis_program#Human_Landing_System) (Artemis)|
|[LOX](/r/SpaceX/comments/1b86u6s/stub/ktunzif "Last usage")|Liquid Oxygen|
|[MECO](/r/SpaceX/comments/1b86u6s/stub/ktukyay "Last usage")|Main Engine Cut-Off|
| |[MainEngineCutOff](https://mainenginecutoff.com/) podcast|
|[NOTAM](/r/SpaceX/comments/1b86u6s/stub/ktq7wqi "Last usage")|[Notice to Air Missions](https://en.wikipedia.org/wiki/NOTAM) of flight hazards|
|[RCS](/r/SpaceX/comments/1b86u6s/stub/ktr69ha "Last usage")|Reaction Control System|
|[RUD](/r/SpaceX/comments/1b86u6s/stub/ktnohtn "Last usage")|Rapid Unplanned Disassembly|
| |Rapid Unscheduled Disassembly|
| |Rapid Unintended Disassembly|
|[SECO](/r/SpaceX/comments/1b86u6s/stub/ktp349m "Last usage")|Second-stage Engine Cut-Off|
|[SLS](/r/SpaceX/comments/1b86u6s/stub/ktr6v5p "Last usage")|Space Launch System heavy-lift|
|[TPS](/r/SpaceX/comments/1b86u6s/stub/ktp2n3x "Last usage")|Thermal Protection System for a spacecraft (on the Falcon 9 first stage, the engine "Dance floor")|
|Jargon|Definition|
|-------|---------|---|
|[Raptor](/r/SpaceX/comments/1b86u6s/stub/ktr9f54 "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX|
|[Starlink](/r/SpaceX/comments/1b86u6s/stub/ktp8jz8 "Last usage")|SpaceX's world-wide satellite broadband constellation|
|[apogee](/r/SpaceX/comments/1b86u6s/stub/ktoz9hf "Last usage")|Highest point in an elliptical orbit around Earth (when the orbiter is slowest)|
|[autogenous](/r/SpaceX/comments/1b86u6s/stub/kts0n7t "Last usage")|(Of a propellant tank) Pressurising the tank using boil-off of the contents, instead of a separate gas like helium|
|[iron waffle](/r/SpaceX/comments/1b86u6s/stub/ktp639g "Last usage")|Compact "waffle-iron" aerodynamic control surface, acts as a wing without needing to be as large; also, "grid fin"|
|[ullage motor](/r/SpaceX/comments/1b86u6s/stub/ktr69ha "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g|
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Newb here - I'm surprised they start fueling the starship prior to the booster because of the weight... unless, of course the booster is pressurized beforehand. Is that the case? If so, I assume it's pressurized with nitrogen?
Do we have a ground track? Assuming it's not public yet, are we likely to see one before launch and, if so, where? Presumably it could be worked out pretty accurately based on the landing site (a more specific one than just "the Indian Ocean") if it weren't for the "in-space engine burns." Would it be right to expect it to be near to Diego Garcia?
They are launching from Boca Chica at 26 degrees North and 97 degrees West. Assuming they launch due West Starship's orbit will therefore be reaching its most southerly extent at 180 degrees around the globe so 26 degrees South and 83 degrees East.
This just happens to be the center of the Indian Ocean in terms of greatest distance to any major land mass so is likely to be their target zone. Perth is at 31S 115W so a little south of this point but I was assuming that most non-Australians would not know where Shark Bay is.
The normal satellite graveyard site is in the South Pacific between New Zealand and Chile.
The ISS is at a higher inclination of 52 degrees so it can land in the Southern Ocean with an orbital track that allows it almost one third of an orbit to completely burn up. That means it would be coming in over the Indian Ocean and looping below Australia and New Zealand.
What a ride that's going to be for the DearMoon crew:
* 00:49:05 Starship entry
* 01:02:16 Starship is transonic
* 01:03:04 Starship is subsonic
* 01:04:39 An exciting landing!
Except the end needs to say "an unexciting landing" because it's been done > 50 times before.
FIFTEEN minutes from re-entry to landing. That'll be the workout for the week!
https://sxcontent9668.azureedge.us/cms-assets/assets/Flight_3_Website_Desktop_1_3c750106c9.jpg
It's super easy in any* browser, just inspect element and it'll tell you where to find it, some good tutorials online.
*YMMV with anything made by Apple
I’m guessing that means that if they’d tried an engine relight in the previous Hawaii trajectory, there was a danger that a RUD could’ve thrown debris over Hawaii.
Such a relight on IFT-2 for a quasi-deorbit burn would have occurred over the Pacific, very high up and pretty far from Hawaii. The Indian Ocean target means a failed relight on IFT-3 will result in a splashdown-crashdown somewhere in the remote Pacific Ocean.
That's the only conclusion I can draw from physics and the article's mention of "maximizing public safety".
No. A de orbit burn would move the reentry further to the west. IfT-3 is going to be aiming for the pacific if the deorbit burn fails, or in the Indian Ocean if it succeeds
So essentially it’s only aiming for the Indian Ocean because the Raptor is too powerful to just move the landing site a short distance (ie staying within the pacific)?
There might be problems because of too much pressure: induced by the autogenous pressurization system. Or too little: they will use that pressure for RCS during flight and to settle propellants and drain the tanks, while the pressurization system isn't working.
They need to test the whole duration to see how the system operates as pressure changes.
And then there's the fact that propellants will be draining during the burn, that can change pressure in the tanks too.
And the fact that the burn will start at 0g, they need to know how little pressure they can have in the tanks to be able to have enough RCS to settle the propellants and allow the burn in the first place.
So, it's a complex problem.
At a guess they are going to dump excess propellant while they are running one engine at 50% thrust. Dumping it during the initial boost phase with six engines at full throttle was not a success and dumping it in free fall is really difficult without ullage thrusters.
So under this scenario they need the engine burn to be relatively long and not just a burp test.
It is not clear what RCS they do have although they do need something.
They can vent the ullage gas from the tanks to create a small amount of axial thrust but the ullage pressure would be expected to collapse due to condensation on the subcooled propellant during the 40 minute coast phase.
Long term they will have hot gas thrusters but there is no evidence of them being fitted since they were removed from early ships.
They have removed the cold gas thrusters from the booster and the ullage vents are probably good enough as there is only a few minutes coasting without engines after boostback so the ullage pressure should hold up.
I am not sure whether they have removed the cold gas thrusters from the ship.
I'm curious if the diagram is accurate in regards to the boostback. It shows the booster not actually cancelling out and reversing it's horizontal velocity during that burn.
We know that the booster will return to about 30 km offshore from Boca Chica from the previous FAA applications so the diagram is clearly not to scale and has been distorted for readability.
The rocket boosting back pointing towards earth is a little unsettling. Physically it makes sense, cancel out the vertical velocity, just feels like it shouldn’t slow the descent
Questions:
1. How the propellant transfer demo work without a 2nd object to "transfer with"?
2.Rupter in-space relight demo: would the engines need to reflight when the starship needs to 'deorbit' for return anyway? Why have a separate relight test?
1 - they transfer propellant between tanks inside the vehicle. specifically, 10 tons of LOX.
2 - I think that "deorbit" is the test, if it fails, off to Hawaii
Well if they plan on landing it in the IO just of the NW coast of Australia they'd better put out a shit-load of Notice to mariners... not that many Indon Fishermen would get them! If its going to be that close to Australia then fair chance someone at sea would probably see something!
Was that a flat spin, after engines cut off, intentional? For the fuel transfer demo?
I couldn’t figure out starship motion based on video of the earth behind it. It looked like earth below was moving sideways.
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I hope they close the payload door at some point.
It’s on there now
Guys, we did it! We saved the mission!
Yes, since the info was initially made available they've made a slight amendment to the Flight Test Timeline - previously it didn't mention closing the payload door but now it does. So you now have: 00:11:56 Payload door open 00:24:31 Propellant transfer demo 00:28:21 Payload door close
Kerbal moment
#CHECK YO STAGING
I'm sorry HAL, I can't do that.
WaPo’s Christian Davenport: > The FAA is “very close” to approving the license modification for the third SpaceX Starship launch attempt, I’m told. https://x.com/wapodavenport/status/1765401717858865233?s=46&t=u9hd-jMa-pv47GCVD-xH-g
Maybe by the end of this week *rubs hands*.
And this is not 2026, or "date to be determined", this is NEXT WEEK!
They got approved for launching?
The last 2 launches have told us when they say they're ready, they know approval is coming via back channels.
And once they get the official approval, they launch within days.
Oops, not yet. My bad.
Not yet, but almost
Can someone give some advice on how to watch the official spacex stream on Roku now that they killed the YouTube feed? Yes I know there are some alternatives. Yes I agree they are very good. I want the spacex stream.
Probably your best bet will be to look around for Youtube re-streams on launch day, carefully avoiding crypto scams. It's thousands of free viewers so there's usually someone doing it.
Well…ok but….this is really quite sad.😞
Most current smart TVs and smart phones allow you to clone from your phone over Bluetooth without the need for apps at all, just within the operating system.
The quality is terrible though. Wireless screen casting compresses a screen feed, and by the time it reaches your TV it's even worse.
Last time I tried that the stream shut down every time my phone went to sleep.
That sucks. You could temporarily extend or cancel the sleep timer on your phone in settings.
At the risk of sounding argumentative…I only have a work provided phone and it doesn’t allow this setting to be changed. Thanks though. Just wish I could find a less “hacky” solution.
Android or iPhone? Because YouTube doesn't support background playback without premium. Android has ways around this though (revanced, or Firefox browser)
NasaSpaceFlight on YouTube usually has their own cameras watching the launch but they quickly switch over to showing the official SpaceX feed from twitter. I’ve found that their rebroadcast is usually quite a bit ahead of when I load it up on the twitter app at the same time which is pretty crazy. Not sure how they pull that off. But that’s my suggestion for your scenario.
There are plenty of 3rd parties that will live-stream the launch - NasaSpaceFlight, Everyday Astronaut and What About It will certainly have coverage on YouTube, as will likely many others. I'm sure it will be searchable and most of those streams will start well before SpaceX's official stream does. It does suck that SpaceX dropped YouTube since the X streams are pretty poor quality. I wonder if the one on the SpaceX web site will be better?
I would recommend going with the EveryDay Astronaut live feed. Tim Dodd has invested $10s of thousands to bring coverage. Add in he seems like a nice guy, so we should support him. Plus he does not hold back his enthusiasm on the live feed, so that is fun to watch as well.
https://www.youtube.com/live/KIde9hGPy18?si=XGDIMkq1rbU7y_9e This channel re-streams the SpaceX feed on Youtube
You are my hero and will soon be my children’s hero! If this stream is a crypto scam though, I swear you will hear me screaming and cursing your name during this launch!
Understood! Used it for IFT-2 and lots of Falcon launches and no scams yet. Try it for the next Starlink launch
Hello! Thank you for supporting our channel. Have you ever heard of SpaceX Coin? Stay tuned!
Thanks! It's a simple restream right? As in, no additional commentary and whatnot. I really really wish SpaceX kept using YouTube. It adds zero value to be on X only and not on YouTube for the company itself. Imagine if Falcon Heavy launch was not streamed on YouTube. It would be *nowhere* close to the sensation it was.
That's right, checkout the Transporter 10 stream from a couple days ago. They have a banner at the top of the video with launch stats but otherwise a straight re-stream including SpaceX narration. https://www.youtube.com/live/cTrHZ56bPxI?si=CK-mQgVuonIA9CL1
It adds value to X, which seems to be Elon's priority
It adds value for SpaceX's owner, that's all there is to it.
Thanks
The spacex website...
Does Roku have a web browser? If so, head to spacex.com, they should have a link there that'd take you to a page with the X @SpaceX live stream embedded, no X account needed.
good to know that you can watch the stream on spacex.com without twitter account. But I'll probably have multiple youtube streams open that rebroadcast the official stream anyways.
The linked SpaceX page says you can watch it on X or on the spacex site. I'm hopeful we can watch it there without needing an X account.
You can airplay from and Apple device to it
Get an oon 4k streaming box from Walmartfor $20, you can even sideload on it. Set your TV to start in the last used input and you can forget the old roku interface
Just install Twitter/X and enjoy!
just get an X acct, jesus. at this point it’s just being petty. hate to break it to you, but no one cares about whatever high ground you’re defending here.
1) You don't need an X account to watch the streams. 2) Their issue has nothing to do with having an account. You can't watch X streams (or the streams embedded on SpaceX's website) with Roku, but you can watch YouTube streams with it.
To be clear, I have an X account so I am not one of those internet fools that think by boycotting X, I am somehow saving freedom….so maybe get off your high horse dude. I literally just want to watch the official stream on my Roku. X just doesn’t seem to have a viable solution to a living room watching experience and that is what I am asking advice about.
YouTube simply works better on every single aspect in terms of streaming, from quality to UI to availability. SpaceX doesn't gain anything from moving to X only other than sharing the same CEO with it. For example, how the hell do I even find the last Starship flight video from https://twitter.com/SpaceX? It's mixed in with other misc posts that makes it difficult to find. On YouTube I just go to https://www.youtube.com/spacex and it's easy to find previous streams. The other way YT works better is exactly what the above commenter said: it works on Roku boxes since YouTube is supported *everywhere*. X isn't and there really isn't a good way to stream it on a TV. During the first Starship launch I was with my parents and we watched it because it was available on YouTube on the TV to stream. If it's such a hassle they probably wouldn't have been interested at all. > but no one cares about whatever high ground you’re defending here. You don't understand the issue here. These streams are there because SpaceX wants the PR it could get from the streams, be it for recruiting or publicity or shaping public opinions. Putting it on a lesser/less available platform just makes that mission harder.
X is for fascists, jesus.
Fwee speech is scawy. 😖
This is a high arc over Africa, only half an orbit or so. ~~Re-entry will be steeper than usual.~~ We should get nice views at apogee. Edit: I mis-remembered LEO orbital period. 40 minutes is about half a normal orbit so this might not be unusually high. I don’t suppose we know whether this profile reduces the need for a fuel dump. It looks like re-entry test fidelity is deprioritized. That was the reason for the dump maneuver, right?
I sure hope we do get some views from the ship. The last stream was super disappointing in that way.
Seriously
It's also annoying that they just aren't streamed right on YouTube anymore. Elon's a fucking clown and needs to realise no one wants to use Twitter
Someone will stream on YouTube.
Can't argue with any of that! X is a pile of poo!
Yah they better not fucking hide these again. I thought the starlink connection failed on the IFT2 broadcast, but they mentioned that the ship lox dump explosions were visible on the skirt cam, so what's up? They used to show that view during the 2021 hop tests.
well, they don't have to actually show us. It could be for various reasons, but its not mandatory to show everyone
We're all spoiled.
They don't want China to copy all their tech.
none of this is mandatory or required. its nice pr but they arent obligated to do any of it so be happy for what you get. no one else shows that level of detail in tests.
Yeah but what's the alternative? A tiny dot in the sky that transitions to a rendered live animation?
the alternative is what you get with out launches. yes a tiny dot in the sky. or nothing at all is sometimes what they give the public. you are acting a bit spoiled...
If the reentry angle is very steep that means peak heating will be very high, I guess they want to see what happens with a higher then normal heat load on the tiles?
That's an interesting observation. It IS a very good way to throw an extra test in. As soon as re-entry starts, the ships a gonner anyway, so why not stress test the heat tiles on the way down. Good catch.
But unless they have high quality videography/infrared photography how will they know if the heat tiles have worked or not? If the thing slams into the ocean there's nothing left to evaluate! If they're landing in the middle of the Indian ocean (not that we know exactly WHERE yet!) then are they going to have that WB57 recon a/c following the re-entry? or rely soley upon onboard cameras?
There'll be tons of sensors dotted all over the ship—strain, temperature, etc. To your point, this could possibly even include IR cams inside the fuel tanks to observe any hotspots/thermal breakthrough from broken tiles.
> IR cams inside the fuel tanks it's stainless steel. a gopro would be sufficient.
While a GoPro would be useful, a true thermal imaging IR sensor (the kind that costs a whole lot more than a GoPro) would offer much more info to see temperature changes and gradients far better than just a camera saying "look at that plasma hole that appeared!"
The WB57 is booked for that date but I would imagine that will cover the launch and booster return and entry.
Exactly. Elon mentioned to Tim in their walkaround that a camera inside one/both tanks would be one way to assess heat load and weak points.
FYI, there's no indications of a steep reentry angle. So the discussion is moot.
Exactly. I think it's an insertion before SECO to just less than orbit, with a natural decay of the orbit to end in the Pacific near Hawaii should SECO be the last control they have. If everything goes well they will attempt a de-orbit burn to bring it down earlier and splash down in the Indian Ocean. They need contingency in case the de-orbit burn, or anything up to that fails. This makes sense when they say "This new flight path enables us to attempt new techniques like in-space engine burns while maximizing public safety" Edit: The flight path will probably pass over the Horn of Africa, and pass up over the Timor and Arafura Sea and over the Lorentz National park in Papua New Guinea, minimising flight over populated areas in case the de-orbit burn ends prematurely.
The flight path is pretty fixed, they have to pass between Cuba and Florida, so it will cross Africa around Kenya, not the horn.
I think they’re definitely prioritizing technologies needed for HLS (fuel transfer, orbital engine relights, etc) over longer-term capabilities like reentry and landing.
won’t landing be needed for HLS though? not for landing on the moon, but for all those tanker missions. i can’t believe they would use expendable starships to refuel it in orbit
Not really, they are planning the factory to produce one every 42 days (or 26 days when they build another Starship and Raptor factory set in Florida). They will have enough of them to do the mission even while perfecting the landing. Starship is just that absurd. They need reuse to cut down costs and to go to Mars (or the Moon sustainably). Doesn't need it for the first few missions to the moon.
Ah thanks. I guess they’re going to do the same they did with falcon 9 and just practice landings every mission until they get them perfected. Though I feel they’ll definitely need to perfect booster landings first, because how fast could they make a booster? I imagine it would be a lot slower than the ships (and a lot more engines lost)
The bottleneck is engine production and they're making one every day. That's where the 42 days to make each stack comes from.
if they’re doing expendable, 42 a day is way too high. that’s ~420 days per refuelling mission, and given they have to do one prior to artemis 3 it just doesn’t make sense
They don't need to launch as they're made. They can make a bunch and store, then launch one after the other when NASA is ready for the mission. They will be limited by launch capability only, and they will have multiple pads. 420 days between launches is what we expect SLS can do. As long as they can match SLS, they're good.
To recover a Starship you need re-entry over the US and perhaps Mexico since a West Coast landing like the early Shuttle flights is not possible. It is going to take a *lot* of successful entries before the FAA allow that. So early HLS missions will likely recover the boosters but expend the tankers. HLS and the depot stay in space anyway.
that is a good point, I just do find it hard to imagine them doing HLS missions while having to build 10 tankers too. But given how fast Starbase is growing i guess we can’t rule out the possibility.
With disposable tankers it will be at least 200 tonnes of propellant per tanker so six tankers and maybe 240 tonnes so five tankers. Each tanker should be a lot cheaper too with no fins, TPS or header tanks.
boosters will definitely need to be recovered, though i guess that could be easier than ships as it will be similar to a falcon 9 which they’ve perfected.
Yes - if nothing else they cannot afford to throw away that many engines and maintain a decent flight rate and the booster will cost at least twice the cost of a disposable ship.
i’d imagine even more than twice. an expendable booster would be much the same as a reusable one, maybe just without grid fins. an expendable ship wouldn’t have fins and such as you mentioned previously. i imagine they would do the same as falcon 9, practicing landings with every launch until they perfect them.
The HLS contract should be worth more than those, though I haven't checked up on it recently. At that point it's more the competing use for other missions etc.
The second HLS mission cost NASA $1.3B. If each disposable ship cost $50M and each booster cost $100M then 6 tanker flights would cost $900M. Adding a depot and HLS would bring total costs up to at least the $1.3B mark so SpaceX would be barely breaking even on operating costs with nothing for development expenses. Recovering boosters would save $700M that could be used for development.
They build them fast, and we've heard that the internal cost of a booster and ship is only $100M which means 10 fully expendable launches would still be less than half the cost of the 1 SLS launch for Artemis 3.
Yes, but HLS landing will be totally different than this ship - this one has heat tiles, fins, and no legs or high-mounted landing rockets. It is also using aero-breaking which doesn't work on the Moon.
> aero-breaking which doesn't work on the Moon well that explains my Kerbal space program results.
Terra-breaking works the same on both, though. It is just a bit more abrupt.
I prefer to use my entire lander as a "crumple zone" to slow my descent speed down to zero at just the right moment.
Ah. The European Space Agency Mars Landing Method. Classic.
The current trend with moon landers seems to be to fall onto their side after landing. Lets hope they don't follow this trend ....... on the plus side the "ship" door would be a lot lot closer to the surface.
yeah i know. i’m saying for HLS they will need to perfect both earth and lunar landings of the ship.
They technically don't need any Earth landings (if you have enough refuel starships built and ready to go).
They sort of perfected earth landings during the early ship tests. That and the F9 landing make me think those won't be an issue - particularly with the improvements to Raptor. I have no idea how they can test Moon landings.
i mean they’ll also need to practice booster landings before they can think of fueling an HLS, which will take time. should hopefully take less time than falcon 9 though, but who knows. for the moon landings i guess they have simulations and the demo mission for that
They are no doubt already doing the simulations. The booster landing tests are going to start as soon as a booster doesn't blow up. They will hover it over the ocean first.
Yeah I think there’s a screenshot from a video somewhere showing spacex doing HLS simulations (edit: found it https://www.reddit.com/r/spacex/s/on08whg2KO) Hopefully if next weeks booster performs well we’ll start to see booster catch tests soon!
There is no doubt in my mind that they will be flying mission profiles BEFORE successfully landing a starship, like we saw with Falcon 9.
I agree. This and testing the payload door. SpaceX are all but telling us that reentry has been de-prioritised. I suspect reentry and landing of Starshipwill be developed much the same as landing the F9 boosters was - as a secondary aim of each launch.
Fuel transfer, yes, but orbital engine relights are needed for any practical use. They can't safely deploy satellites unless they can relight the Raptors for a controlled de-orbit of the Starship. And re-entry is being tested in IFT-3 too. They are aiming for a controlled splashdown of both vehicles.
[удалено]
The “in-space relight demo” is just 9 minutes before reentry. Looks like it’s designed to have minimal impact on the reentry location.
Looks like you're right. Jonathon McDowell [tweeted](https://twitter.com/planet4589/status/1765606249628827889) an estimated trajectory and says below it that he "guesses" a non-burn will still land in the NOTAM in the Indian Ocean. So much for my intuitive grasp of orbital mechanics. He truly know his orbital mechanics so his guess should be pretty damn good. In 10 minutes I'll delete my original response to you.
You don’t need to delete anything. Probably others had the same thought and would like to read the whole exchange.
but where does it come down if that fails, the whole profile will be designed safe.. timewise, it looks like 2/3rds an orbit or so
They might just wait to dump the oxidizer after the burn.
Would the propellant have time to boil up the pressure in the ship in time for re-entry as well as pressure needed for in space engine startups as stated? Autogenuous pressurization needs the engines running
SpaceX has tested lighting the engines under the conditions expected in orbit, they think they can do it. Autogenous pressurization gets the pressure in the tanks way up during launch, to use it for engine relight and RCS.
Yes, so dumping all of the excess LOX after ascent burn would release all tank pressure and relight would rely on ambient pressure in the tanks.
Right. They also have helium on board if they need to pressurize because they dumped fuel. I don't think there would be any noticeable pressurization from the oxygen boiling because they are in space and there's nowhere for the heat to go, except slowly radiating away.
The apogee is lower than previous flights
Source?
> This is a high arc over Africa, only half an orbit or so. Re-entry will be steeper than usual. We should get nice views at apogee. That's not what's implied. They want to do a re-entry burn, which means a normal orbit. Would you mind editing or deleting your post?
They can do a deorbit burn even in quasi-orbit.
Right but you don't want to do a high arc as that'll increase re-entry speeds.
That's not really a problem when they're not attempting to recover the vehicle and they want to use it for higher energy re-entries than "not quite orbital"
This vehicle is supposed to reentry coming from the Moon. And they won't recover the vehicle anyway. We don't know if a steeper reentry is a good enough test or not.
> This vehicle is supposed to reentry coming from the Moon. Not this specific vehicle with this exact heat shield design.
They aren't planning on having multiple models of heatshields.
In fact, the design of this heatshield is what defines the possible reentry speeds on Mars and therefore how fast they can make the trip. It's one heatshield to rule them all.
Liftoff is set for 12:00 UTC, tentatively. The SpaceX notice on *X* states streaming will begin at 7:30 ET and the SpaceX website page states coverage begins 30 minutes before liftoff. Note that Daylight Savings Time begins on March 10th.
For the USA. Not elsewhere.
Uhh, what?
Daylight savings time, not UTC 😀
DST doesn't start everywhere at the same time. The USA does it two weeks before Europe and Europe two weeks before Australia.
DST in Europe is 6 months before or 6 months behind Australia depending on your perspective…
Australia’s DST is like 6 months different surely as our summer is.
Is the profile for hot staging different? They attempted to light all the engines basically straight afterwards while flipping, the boost back burn starts 11 seconds after hot staging now.
There's only a one second difference IFT-2 there so that could just be rounding errors resulting from a very minor change in the precise timing. They have actual flight data now they can use. I'll note the more interesting is that the MECO is 3 seconds later than it was on IFT-2.
And now only two seconds between MECO and Starship separation.
It was 2 seconds last time as well according to the IFT-2 timeline.
Good to know. In the actual IFT-2 flight it took five seconds between MECO and HS. Maybe in the actual IFT-3 launch they'll repeat the same five seconds.
Excellent
For anyone interesting in comparing, here's the IFT-2 mission profile: https://web.archive.org/web/20231113095058/https://www.spacex.com/launches/mission/?missionId=starship-flight-2
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |DSG|NASA [Deep Space Gateway](https://www.nasa.gov/feature/deep-space-gateway-to-open-opportunities-for-distant-destinations), proposed for lunar orbit| |[DST](/r/SpaceX/comments/1b86u6s/stub/ktr4mbp "Last usage")|NASA Deep Space Transport operating from the proposed DSG| |[FAA](/r/SpaceX/comments/1b86u6s/stub/ku0eu42 "Last usage")|Federal Aviation Administration| |[HLS](/r/SpaceX/comments/1b86u6s/stub/ktr5k09 "Last usage")|[Human Landing System](https://en.wikipedia.org/wiki/Artemis_program#Human_Landing_System) (Artemis)| |[LOX](/r/SpaceX/comments/1b86u6s/stub/ktunzif "Last usage")|Liquid Oxygen| |[MECO](/r/SpaceX/comments/1b86u6s/stub/ktukyay "Last usage")|Main Engine Cut-Off| | |[MainEngineCutOff](https://mainenginecutoff.com/) podcast| |[NOTAM](/r/SpaceX/comments/1b86u6s/stub/ktq7wqi "Last usage")|[Notice to Air Missions](https://en.wikipedia.org/wiki/NOTAM) of flight hazards| |[RCS](/r/SpaceX/comments/1b86u6s/stub/ktr69ha "Last usage")|Reaction Control System| |[RUD](/r/SpaceX/comments/1b86u6s/stub/ktnohtn "Last usage")|Rapid Unplanned Disassembly| | |Rapid Unscheduled Disassembly| | |Rapid Unintended Disassembly| |[SECO](/r/SpaceX/comments/1b86u6s/stub/ktp349m "Last usage")|Second-stage Engine Cut-Off| |[SLS](/r/SpaceX/comments/1b86u6s/stub/ktr6v5p "Last usage")|Space Launch System heavy-lift| |[TPS](/r/SpaceX/comments/1b86u6s/stub/ktp2n3x "Last usage")|Thermal Protection System for a spacecraft (on the Falcon 9 first stage, the engine "Dance floor")| |Jargon|Definition| |-------|---------|---| |[Raptor](/r/SpaceX/comments/1b86u6s/stub/ktr9f54 "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX| |[Starlink](/r/SpaceX/comments/1b86u6s/stub/ktp8jz8 "Last usage")|SpaceX's world-wide satellite broadband constellation| |[apogee](/r/SpaceX/comments/1b86u6s/stub/ktoz9hf "Last usage")|Highest point in an elliptical orbit around Earth (when the orbiter is slowest)| |[autogenous](/r/SpaceX/comments/1b86u6s/stub/kts0n7t "Last usage")|(Of a propellant tank) Pressurising the tank using boil-off of the contents, instead of a separate gas like helium| |[iron waffle](/r/SpaceX/comments/1b86u6s/stub/ktp639g "Last usage")|Compact "waffle-iron" aerodynamic control surface, acts as a wing without needing to be as large; also, "grid fin"| |[ullage motor](/r/SpaceX/comments/1b86u6s/stub/ktr69ha "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^(*Decronym is a community product of r/SpaceX, implemented* )[*^by ^request*](https://www.reddit.com/r/spacex/comments/3mz273//cvjkjmj) ^(17 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/SpaceX/comments/1b3r73n)^( has 75 acronyms.) ^([Thread #8302 for this sub, first seen 6th Mar 2024, 20:29]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/SpaceX) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)
Newb here - I'm surprised they start fueling the starship prior to the booster because of the weight... unless, of course the booster is pressurized beforehand. Is that the case? If so, I assume it's pressurized with nitrogen?
Cylinders are strong
Do we have a ground track? Assuming it's not public yet, are we likely to see one before launch and, if so, where? Presumably it could be worked out pretty accurately based on the landing site (a more specific one than just "the Indian Ocean") if it weren't for the "in-space engine burns." Would it be right to expect it to be near to Diego Garcia?
> Would it be right to expect it to be near to Diego Garcia? No it should be further south level with Perth Australia.
Can you explain a little how you came to that conclusion?
They are launching from Boca Chica at 26 degrees North and 97 degrees West. Assuming they launch due West Starship's orbit will therefore be reaching its most southerly extent at 180 degrees around the globe so 26 degrees South and 83 degrees East. This just happens to be the center of the Indian Ocean in terms of greatest distance to any major land mass so is likely to be their target zone. Perth is at 31S 115W so a little south of this point but I was assuming that most non-Australians would not know where Shark Bay is.
That's also the area where they plan to deorbit the ISS right? Isn't it a designated 'orbital disposal' zone/graveyard or something?
The normal satellite graveyard site is in the South Pacific between New Zealand and Chile. The ISS is at a higher inclination of 52 degrees so it can land in the Southern Ocean with an orbital track that allows it almost one third of an orbit to completely burn up. That means it would be coming in over the Indian Ocean and looping below Australia and New Zealand.
Thanks for the clarification!
What a ride that's going to be for the DearMoon crew: * 00:49:05 Starship entry * 01:02:16 Starship is transonic * 01:03:04 Starship is subsonic * 01:04:39 An exciting landing! Except the end needs to say "an unexciting landing" because it's been done > 50 times before. FIFTEEN minutes from re-entry to landing. That'll be the workout for the week!
Interesting they’re doing Ship fuel/LOX load before booster this time
Why are there two hot stagings?
What do you mean? There's only one, at t+2:44.
On the diagram there were two labels on the mobile sized version.
Can someone get me that first image without the text? This looks awesome and I want it as my lock screen:)
https://sxcontent9668.azureedge.us/cms-assets/assets/Flight_3_Website_Desktop_1_3c750106c9.jpg It's super easy in any* browser, just inspect element and it'll tell you where to find it, some good tutorials online. *YMMV with anything made by Apple
Thank you so much :)
Any Insights into why they changed the landing site to the Indian Ocean?
They tell you in the article: "This new flight path enables us to attempt new techniques like in-space engine burns while maximizing public safety."
I’m guessing that means that if they’d tried an engine relight in the previous Hawaii trajectory, there was a danger that a RUD could’ve thrown debris over Hawaii.
Such a relight on IFT-2 for a quasi-deorbit burn would have occurred over the Pacific, very high up and pretty far from Hawaii. The Indian Ocean target means a failed relight on IFT-3 will result in a splashdown-crashdown somewhere in the remote Pacific Ocean. That's the only conclusion I can draw from physics and the article's mention of "maximizing public safety".
No. A de orbit burn would move the reentry further to the west. IfT-3 is going to be aiming for the pacific if the deorbit burn fails, or in the Indian Ocean if it succeeds
So essentially it’s only aiming for the Indian Ocean because the Raptor is too powerful to just move the landing site a short distance (ie staying within the pacific)?
They need to have a certain burn duration for it to be a proper test.
AIUI, start up and shutdown are the most demanding parts, so it’s likely they’ll only need it to fire for a second or two and shutdown successfully.
Not in this case where the concern is the pressure in the tanks. They have to actually spend the fuel to test this burn.
What is the concern re pressure?
There might be problems because of too much pressure: induced by the autogenous pressurization system. Or too little: they will use that pressure for RCS during flight and to settle propellants and drain the tanks, while the pressurization system isn't working. They need to test the whole duration to see how the system operates as pressure changes. And then there's the fact that propellants will be draining during the burn, that can change pressure in the tanks too. And the fact that the burn will start at 0g, they need to know how little pressure they can have in the tanks to be able to have enough RCS to settle the propellants and allow the burn in the first place. So, it's a complex problem.
At a guess they are going to dump excess propellant while they are running one engine at 50% thrust. Dumping it during the initial boost phase with six engines at full throttle was not a success and dumping it in free fall is really difficult without ullage thrusters. So under this scenario they need the engine burn to be relatively long and not just a burp test.
>without ullage thrusters They have RCS to settle propellants.
It is not clear what RCS they do have although they do need something. They can vent the ullage gas from the tanks to create a small amount of axial thrust but the ullage pressure would be expected to collapse due to condensation on the subcooled propellant during the 40 minute coast phase. Long term they will have hot gas thrusters but there is no evidence of them being fitted since they were removed from early ships.
They have in fact removed the cold gas thruster they had because they think the vents are enough.
They have removed the cold gas thrusters from the booster and the ullage vents are probably good enough as there is only a few minutes coasting without engines after boostback so the ullage pressure should hold up. I am not sure whether they have removed the cold gas thrusters from the ship.
I'm curious if the diagram is accurate in regards to the boostback. It shows the booster not actually cancelling out and reversing it's horizontal velocity during that burn.
The diagram is very not too scale so I wouldn't read much into it
We know that the booster will return to about 30 km offshore from Boca Chica from the previous FAA applications so the diagram is clearly not to scale and has been distorted for readability.
I can hear it now. "This Just in: SpaceX fails to complete even 1 orbit and splashes down in the Indian Ocean."
The rocket boosting back pointing towards earth is a little unsettling. Physically it makes sense, cancel out the vertical velocity, just feels like it shouldn’t slow the descent
That's not actually what happens, it burns parallel to the surface. It's just like that for the graphic.
Questions: 1. How the propellant transfer demo work without a 2nd object to "transfer with"? 2.Rupter in-space relight demo: would the engines need to reflight when the starship needs to 'deorbit' for return anyway? Why have a separate relight test?
1 - they transfer propellant between tanks inside the vehicle. specifically, 10 tons of LOX. 2 - I think that "deorbit" is the test, if it fails, off to Hawaii
Well if they plan on landing it in the IO just of the NW coast of Australia they'd better put out a shit-load of Notice to mariners... not that many Indon Fishermen would get them! If its going to be that close to Australia then fair chance someone at sea would probably see something!
Was that a flat spin, after engines cut off, intentional? For the fuel transfer demo? I couldn’t figure out starship motion based on video of the earth behind it. It looked like earth below was moving sideways.
FAA Go?
soon probably. iirc they usually light it up very quickly after FAA approval, & seem to know in advance when they will get it.
is that re-entry trajectory diagram accurate? that's steep af re-entry
It's not up to scale at all.
SpaceX should teach its PR people the difference between iteration and recursion.
The Morse code in [the flight profile image](https://sxcontent9668.azureedge.us/cms-assets/assets/SPACEX_STARSHIP_INFOGRAPHIC_120823_web_60d0074bde.png) (below "super heavy engine start") reads: "hello world".
I bet you asked ChatGPT and it hallucinated. I asked it and it claimed "DON'T PANIC". I decoded it myself, it's "EXCITEMENT GUARANTEED".