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364 points metalman | 21 comments | | HN request time: 0.001s | source | bottom
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2OEH8eoCRo0[dead post] ◴[] No.45033871[source]
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1. sbuttgereit ◴[] No.45033968[source]
I think Scott Manley's position on the "still hasn't gotten to orbit" take is probably still the best and most accurate:

https://www.youtube.com/watch?v=8htMpR7mnaM&t=420s

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2. pclmulqdq ◴[] No.45034151[source]
What Scott is missing is that the only reason "it did not get to orbit" is of interest at all is that SpaceX keeps claiming they got to orbit with starship. I believe that the trajectories have all been suborbital by design, but it still pisses me off that they keep claiming they got to orbit.

The reason this matters is that if they get into an orbit in a short test, they need to exit that orbit with some sort of active system. So the statement "we got to orbit" implies a lot more technology development than the current flights actually show. I agree with Scott that Starship can easily enter LEO, but I am not so sure it can exit gracefully.

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3. rlt ◴[] No.45034304[source]
What exactly do you think is the “more technology development than the current flights actually show“ needed to get into and out of orbit?

My impression is they just need to leave the engines on a little longer to get to orbit, then turn them on again with the ship pointed in another direction to get back to the suborbital trajectory they’ve already demonstrated deorbiting from.

The hard part is reentering through the atmosphere without burning up, flipping, and landing, which they’ve already demonstrated multiple times. There’s no additional atmosphere between where they’ve flown and “orbit”.

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4. bagels ◴[] No.45034354{3}[source]
A little more longevity and one more engine restart, unless the suborbital is very suborbital, then it also means a lot more delta v. It doesn't seem that far away at all.
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5. sbuttgereit ◴[] No.45034390[source]
Where are they claiming that?

For example, this is from their Flight 4 press release (https://www.spacex.com/launches/starship-flight-4):

"Flight 4 ended with Starship igniting its three center Raptor engines and executing the first flip maneuver and landing burn since our suborbital campaign, followed by a soft splashdown of the ship in the Indian Ocean one hour and six minutes after launch."

Note that they clearly say since the start of their suborbital campaign. And this from their Flight 6 press release (https://www.spacex.com/launches/starship-flight-6):

"Starship completed another successful ascent, placing it on the expected trajectory. The ship successfully reignited a single Raptor engine while in space, demonstrating the capabilities required to conduct a ship deorbit burn before starting fully orbital missions. With live views and telemetry being relayed by Starlink, the ship successfully made it through reentry and executed a flip, landing burn, and soft splashdown in the Indian Ocean."

And from today's pre-launch press release (https://www.spacex.com/launches/starship-flight-10):

"The Starship upper stage will again target multiple in-space objectives, including the deployment of eight Starlink simulators, similar in size to next-generation Starlink satellites. The Starlink simulators will be on the same suborbital trajectory as Starship and are expected to demise upon entry. A relight of a single Raptor engine while in space is also planned."

To be fair, there were two press releases where they didn't correctly use "sub-orbital" and used orbital instead. Releases 3 and 9. Neither said they achieved orbit, but more causally talked about the "orbital coast" and the worst: "Starship's six second stage Raptor engines all started successfully and powered the vehicle to its expected orbit" from flight 3. It's true these statements are incorrect, but they aren't asserting a direct claim to having reached orbit (though they imply it), when they make an assertion about the nature of the program they seem fairly consistent in talking about their "suborbital campaign" as well as talking about their orbital missions being in the future.

The way I'm reading it, it looks like they get sloppy with language sometimes, but it doesn't look like they are directly asserting anything other than being in a suborbital program.

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6. kragen ◴[] No.45034410[source]
Is it really a lot more technology? If they were landing 100 km away I'd agree, but aren't they basically reaching the required orbital speed and reentering and landing under retrorocket control? I'm no expert on orbital dynamics, so I might be missing something important.
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7. sbuttgereit ◴[] No.45034475{4}[source]
What's surprising is that people are still resorting to this silly complaint about not reaching orbit when there's a perfectly sensible complain they could be making instead: that SpaceX hasn't yet demonstrated that they can reach orbit and return safely. The safe return is important because I would expect a failure to return safely to be a big deal: it's not like this thing is going to completely burn up if they don't have control during a deorbit. The inadequate retry thermal protection is a large issue even if the Ship has managed to get to the landing areas on target and soft land in the right spot: the burn through on the control surfaces seems to mean that was as much luck as good engineering that the thing didn't crash somewhere less intended.

I appreciate none of that is as pithy as saying it simply didn't reach orbit, but it's a real concern versus something that is really irrelevant.

replies(1): >>45034786 #
8. sbuttgereit ◴[] No.45034495{3}[source]
They're never reaching orbital velocity on purpose. The reason is that they're still proving that they can fire rockets and deorbit under control; until they do that, any problem automatically puts the ship in the ocean no matter what while if they go to orbit and can't control the deorbit they end up possibly causing a disaster.

Now, they are getting it to pretty damn close to orbital velocity... which is why saying they still haven't reached orbit is a bit silly. They're clearly technically able to reach orbit if they really want to... that they haven't proved they can safely leave orbit is the problem.

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9. itishappy ◴[] No.45034574{4}[source]
They tested that extra restart as part of today's flight. I think the only thing now missing is carrying the extra fuel.
10. bryanlarsen ◴[] No.45034786{5}[source]
Starship returned safely. Safe return of orbital generally means a splashdown within 1500 miles of Point Nemo. They just demonstrated that they can splash down within meters of their target buoy. Even if the flaps failed completely they still would have been far less than 1500 miles off target.
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11. sbuttgereit ◴[] No.45034993{6}[source]
They've done so more than than this time, too. Granted, with a little less "Ship" than they left with on all occasions I know of.

No one (at least not me or anyone I take seriously) is arguing whether or not these suborbital profiles are designed to be safe even under adverse or full failure conditions; though the Caribbean air corridors might have been managed a bit more gracefully on some previous flights... still...

Nonetheless there is a valid criticism that in ten flights they still haven't mastered keeping the control surfaces of the space craft whole during the reentry phase of flight. 1500 miles isn't going to cut it as a safe return zone when they try bring this in for a catch. While I'm as impressed as anyone that they've hit the mark with compromised Ships as many times as they have, neither Port Isabel nor Titusville are 1500 miles from their nearest Ship catch towers and I wouldn't support any attempts for a catch until they can get the whole Ship back in good working order... reliably. While I'm a advocate for this program and SpaceX... I'm not such a fanboy that I can't see there are issues with this aspect of the program. This is ignoring the impact on rapid reusability and simply focusing on the basic safety of the program.

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12. Tepix ◴[] No.45035628{6}[source]
Point nemo is in the Pacific Ocean, it landed in the Indian Ocean.
replies(1): >>45035826 #
13. JumpCrisscross ◴[] No.45035826{7}[source]
What’s the point in the Indian Ocean they aimed for called?
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14. verzali ◴[] No.45039976{8}[source]
"far enough from land not to risk hitting anyone"
15. verzali ◴[] No.45039995{4}[source]
Like turning back 300ft below the summit of everest because you aren't confident you have enough daylight to make it back if you do go for the top
16. bryanlarsen ◴[] No.45040137{7}[source]
Port Isabel is 6 miles away from Boca Chica. They demonstrated on a previous mission that they can land within meters of their target despite burnt out flaps. If SpaceX tries to catch Starship their launch tower might not be safe, but Port Isabel would be safe.

But they haven't tried to catch Starship yet and likely won't for a while, so you're arguing a silly hypothetical.

17. pclmulqdq ◴[] No.45042159{4}[source]
A zero-G engine restart is the big piece of technology.
18. pclmulqdq ◴[] No.45042168{3}[source]
A zero-G engine restart to break orbit is the technology. And yes, it is a lot more technology given how the engines work.
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19. kragen ◴[] No.45042234{4}[source]
Oh! Thank you!
20. pclmulqdq ◴[] No.45042451{3}[source]
I have most heard this in terms of "orbital velocity" and "orbital trajectory," as well as statements from the announcers on their livestreams, who are SpaceX spokespeople whether you want to excuse them or not, of "we reached orbit." I agree that if you look at their carefully-crafted press releases, there are fewer exaggerations than if you look at other communications. Even so:

> To be fair, there were two press releases where they didn't correctly use "sub-orbital" and used orbital instead. Releases 3 and 9.

Another example of an official communication is a March 14, 2024 Musk tweet after a rocket did not reach orbital velocity:

> Starship reached orbital velocity! Congratulations @SpaceX team!!

Orbital velocity at the altitudes they target is 28-30 km/h. They consistently stop their tests at about 26 km/h. This is not to say the rocket can't make it to orbital velocity, just that it didn't.

"They get sloppy with their language sometimes" is a good way to excuse repeated lies. If this were a company you were less of a fan of, "they get sloppy with their language sometimes" probably wouldn't fly for you, either. Getting called on their bluffs about this is probably the reason they have gotten more precise about their language.

By the way, it is my opinion that it is time to cancel the entire Artemis program and both of its failures of rocket technology. If SpaceX wants to continue to develop Starship, it should do so without federal funding. I would have no problems with the Starship program if not for the use of public money.

21. Tepix ◴[] No.45042732{8}[source]
near the northwestern coast of Australia