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Totally reasonable question. This is the first rocket ever that will (assuming further success) land in its entirety back on the launch pad, refuel, and go back to orbit the same day.

Imagine that every time an airliner landed its cockpit was destroyed and you had to build a new one. A fully reusable airplane would be a transformational improvement. That's the level of achievement we're talking about here.

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> go again the same day.

That seems like a stretch. What is the actual turnaround time for Starship? fwiw the Shuttle had a lot of lofty promises of reusability that were technically true as long as you didn't consider how long the turnaround time was.

It's a good question. The hurdle to clear for same-day reuse will be the heat shield. SpaceX hasn't yet demonstrated that Starship can reenter the atmosphere and remain fully intact. Doing it while sustaining near zero wear on the heat shield will be even harder. But I think it is not impossible, and I don't know of any other obvious blockers for same day reuse.

Even if they can reuse the booster, it would be huge.

They'll likely reuse the booster on the same day well before the starship portion. No heat shield on the booster. Some starships will likely stay in space for a long time before returning.

Musk has said they're aiming for hundreds of reuses for the booster and dozens for the ship.

It's certainly looked fully intact when reaching ground.

When they manage to do the intended landing it should be pretty unharmed, but I'm sure it will take a while before same-day reuse is attempted.

One of the flaps burned through again. Not as bad as the first time. The hinge area seems like the hardest challenge.

Is this a bit of over engineering? How much is drag reduced during liftoff by having the flaps folded?

The reason the flaps move is to provide attitude and speed control during reentry. Like a skydiver spreading their arms and legs.

oh, you mean like actual flaps of pretty much any aircraft. doh! i was thinking it was like the folding of the wings for planes on an aircraft carrier. sometimes my brain, boy, i don't know

It was a flap hinge that burnt through, not the flap. They have a solution for block 2 which we'll likely see in test 7 -- move the flap slightly further back so that the hinge isn't in direct flow.

Zero wear is not necessary. The tiles can be thicker than the minimum, and be reusable until they wear down to the minimum. Like the brake pads on your car.

With the Falcon 9 they're already at over 100 launches this year. It's multiple rockets, but the turn around is pretty quick and getting quicker every year. They're designing starship from the start with same day turnaround in mind. I wouldn't bet against it I guess.

Some of SpaceX's first stages are getting close to the individual Shuttles' launch counts, with substantially less turnaround time and cost than Shuttle ever had.

Starship has work to do, but it's hard to argue they're not at least on the right path.

Also, less cost in life.

SpaceX was able to re-fly a Falcon 9 in 3 weeks, and it was reported[0] that the refurb process only took 9 days. So they're well on their way.

It's also worth noting that Booster (the first stage), Starship (the second stage) and Raptor (the rocket engine) were all designed with the benefit of the above experience and with the goal of same-day reuse in mind. They know where all of the refurb time went and where the bottlenecks are.

I have no doubt that they can reduce the turnaround further, but the goal of same-day re-flight does seem mighty ambitious.

[0] https://www.teslarati.com/spacex-falcon-9-new-booster-turnar...

The previous flight was October 13, 2024, so while I can't speak to every day, one month turnaround is a reality.

It's a completely different booster and ship that's flying.

And both are already outdated - flight seven (Ship 33) introduces a new generation of hardware. They're moving fast with these.

The shuttle boosters required rebuilding / refueling (which is solid rocket goop) and the fuel tank was completely lost and required rebuilding. The head shield tiles were extremely fragile on the shuttle.

It was never a fully reusable design, just more reusable than before.

SpaceX plans to have no parts that are lost each flight and is working to make the tiles mostly standardized and less sensitive to faults.

Are they going to replace all the tiles before it can relaunch? And what about the engine nozzles? They must be taking quite the beating.

No doubt SpaceX has very smart people working on this and I'm not an expert in material science, but I just find it hard to believe that same day turnaround could be possible. If true, that would really make us a confirmed space faring civilization. We could actually start colonizing Mars.

> what about the engine nozzles?

Falcon 9 has reflown in just over 4 hours [1]. (EDIT: Operational turnaround. Nozzles have been turned around allegedly without refurb in 3 weeks.)

[1] https://en.m.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_...

No, those were separate craft, on opposite sides of the country. It demonstrates an ability to manage multiple missions at once, but not rapid booster turnaround.

https://www.space.com/spacex-starlink-launch-doubleheader-ju...

They've since done two flights in about an hour with https://spaceflightnow.com/tag/starlink-9-5/ and https://spaceflightnow.com/tag/starlink-8-10/

I think the first-stage turnaround record is something like two weeks.

https://en.wikipedia.org/wiki/List_of_Falcon_9_first-stage_b...

> B1062 booster holds the record for fastest turnaround at 21 days. It launched on 8 April and again on 29 April 2022.

For context on JumpCrisscross's comment in this thread: the 4 hours is between two separate launches on two separate rockets. This is absolutely not refurbishing and launching the same rocket 4 hours apart.

Seems like the actual record for turning around the same booster is 21 days, which is still quite impressive.

https://www.teslarati.com/spacex-falcon-9-new-booster-turnar...

The heat tiles are reusable, just like the Shuttle's. They are basically just a material that insulates very well, instead of a traditional ablative heat shield that burns away. With the space shuttle they ended up spending a lot of time inspecting each tile for damage and replacing cracked tiles. SpaceX has a modern iteration of the same material, hopefully with fewer cracks.

Other factors that work in SpaceX's favor are 1) that most launches will be unmanned, meaning they can take bigger risks than the Space Shuttle program; 2) that the steel body of Starship can handle higher temperatures than the Space Shuttle's aluminum, so a compromised heat shield is more tolerable; 3) for now they have a secondary ablative heat shield below the tiles (that does have to be replaced when it gets used, but that should only happen when tiles fall off)

Beware the dunning-kruger effect. There is a lot more to colonizing mars than reusable rockets. Just saying..

For the Super Heavy booster, SpaceX is targeting a <1hr turnaround time. For the ship, it gets a bit more complex. Ships have to make complete orbits before returning, and generally they have to be loaded with cargo as well. Tanker Starships for lunar/Mars missions will probably have pretty quick turnaround given that fuel can be loaded on the pad; other ships will have significantly longer turnarounds.

Is there such a need for a heavy launch rocket to launch routinely?

If we want to establish long term bases on the Moon or Mars then yes, you need not only to send crew and habitation modules but ongoing supplies and equipment.

Other use cases include launching and maintaining satellite constellations (Starling / Starshield), and launching singular large payloads like space telescopes.

Even for smaller payloads, having both the first and second stages be reusable will reduce launch costs.

If satellites don't have to worry as much about weight constraints they can be made cheaper and quicker. Space missions can become more routine.

SpaceX already launches multiple times per month just to maintain Starlink. That will be much cheaper with Starship while enabling larger and more capable satellites. In fact, it's likely that one of the reasons SpaceX built Starlink is to create their own customer (and spur competitors) to plausibly use a significant fraction of Starship's capabilities. None existed at the time.

In the near term the biggest reason to do multiple launches in a day will be orbital refueling. This is required for sending much, much larger payloads to the Moon and Mars. It will require on the order of 10 launches to fuel up one moon lander in orbit, and obviously doing that as quickly as possible will be beneficial. NASA has already committed to this plan for Artemis.

> It will require on the order of 10 launches to fuel up one moon lander in orbit

Require, or just make comfortable? Saturn V had the lift capacity of "only" a couple of Falcon Heavies, but was enough to carry astronauts, a car, a lunar lander with enough fuel to take off, and a command module.

We're not trying to do Apollo again. That would be easier, but we want to build a base this time. For that we need to send a lot more mass and it needs a lot more fuel.

Require. I answered that in this same subtopic.

It's necessary because the Starship upper stage is so heavy. With a non reusable upper stage Starship's capacity would be enormous.

Also because of the Lunar Gateway part of the plan. That pretty much just serves to waste fuel and funnel taxpayer money to the companies funding several congressmembers' election campaigns.

Is that true? SpaceX [0] gives the capacity as 150t reusable or 250t expendable, which is significant, but not enough to make one "enormous".

If you really got order-of-magnitude gains from an expendable upper stage, it wouldn't be that exciting to have reusable rockets (which are more complex and still only fly one order of magnitude more times) in the first place.

[0] https://www.spacex.com/vehicles/starship/

If the upper stage wasn't designed to be reusable, it'd probably have a lot less structural dry mass - no heat shield, no fins, possibly different geometry (depending on how much volume they wanted). It might also be possible to drop the sea-level Raptor engines and just use the more efficient vacuum Raptors. I don't think you'd get an order-of-magnitude difference, but it'd be significant, especially for higher-energy trajectories than LEO.

I don't understand why they don't make such an upper stage. It would allow them to refine the booster design and catch logistics while also launching payloads.

My guess would be that it would take too much extra design work. Making the current upper stage reusable is necessary for the HLS contract anyways, and they've got a lot of work to do already on refining the heat shield & fin protection, enabling landing, and working on propellant transfer.

They are making an upper stage with no fins or heat shield. It's called HLS. But they don't need it just to launch payloads to orbit. Starship has such a bonkers huge payload capacity already that it's plenty for now. Nobody is asking for more yet. Testing Starship reentry is super important too, so it makes sense to do it on every launch until it's perfected.

Needs tend to develop once the means are there.

200 years ago, there was no need to use electricity. 100 years ago, there was no need to use a programming language. 30 years ago, there was no need for gigabit wireless Internet.

Nobody will ever need more than 640k of RAM.

Or perhaps earlier and closer to the heart of USA's citizens, 300 years ago, there was no need for rail lines and trains.

> Needs tend to develop once the means are there.

Counterexample: space stations. We've had small manned space stations for decades now, but no real application for them. They're national prestige items only.

Because launch cost is expensive. There are a lot of interesting things we can develop in zero gravity if the cost per pound was cheap.

Not true! The ISS has functioned as an outpost for science- 3,000+ experiments and counting

https://www.nasa.gov/missions/station/five-space-station-res...

And most importantly for anyone who cares about space the way Elon claims to: The ISS has done pretty much all the research we have on how humans survive in space.

The hazards of living in zero-G were understood at the end of the Mir era.

This feels like tautological reasoning. Since you said, "tend" - are there any counter examples that you can think of?

Some marginal ones.

We have the means to build pyramids or moa statues (Easter Island-style) much more quickly and efficiently that the ancients did, but we don't feel the need anymore.

Yes, obviously.

It takes a heavy launch rocket to launch heavier things into space or missions, refueling, and to goto other planets.

It's a mandate for the next Artemis Mission. [1]

The HLS (Spaceship) will need many refuels at orbit in order to get to the Moon and back. That means at least a dozen of fully-loaded Heavy launches to LEO just so each one of them can load a bit of fuel into HLS. The fuel in orbit can't sit idle for too long, or it deteriorates; I haven't found a limit on days for that, but a week-long launch window is considered a dealbreaker, we're talking a dozen Heavy launches in a week.

It's either a short launch window, or at least 6 Starships built and launched twice in ~10 days. Don't count out on SpaceX building 12 Heavy Starships just for that Artemis mission.

[1] https://en.wikipedia.org/wiki/Artemis_III

Yes, to do anything at all in the rest of the universe.

We are insatiably curious explorers. The cosmos calls to us. Many are willing to do anything they can to answer that call.

Think about it, Starship enables a new era of military dominance in space. Military stuff is notoriously heavy.

Besides, Elon is the first to go after supervillain territory.

He's already spent the $3bn funding that was supposed to deliver the rocket to the moon and back.

That's just straight up not true. The $3bn were never meant to fund the entire project in the way you imply.

That is totally false, but you are not the first person I have heard spread this roomer.

You can go to the official govenrment website and look at the contract, it tells you exactly how much has been paid out and how much has not been. The money is getting out as SpaceX hits development milestones.

I don't remember, exactly but about 2.x billion $ were paid out so far. The money is spread over 40ish milestones. And they have done like 25 or so by now.

To get the full pay out, they will be required to land on the moon and take off again. Those are likely the last couple milestones.

I think the economics of space are are much more likely to be transformed by something like https://www.longshotspace.com/. Rockets are complex, still costly, and polluting.

The problem with space guns is you can't just yeet rocks into orbit. Any orbit that starts at the surface returns to the surface. So you still need a disposable rocket and avionics and fuel in every payload to change the orbit once out of the atmosphere. Only now the rocket needs to survive being literally shot out of a gun and then traveling at orbital velocity in atmosphere. That puts a pretty high floor on the cost per shot.

Plus, your payload needs to be gun compatible. Not gonna put people in there.

Well, in WW2 we did manage to put working radar in artillery shells.

With vacuum tubes, no less!

Space is for robots.

While mass to orbit costs as much as it does now, sure. However later on it's gonna be great to have humans closer to the working robots to reduce the round-trip latency. They could also perform tasks robots are not suited for.

Consider operators living on Mars and operating drones near their habitat each day. It would be like modern day drone operators and robot assisted surgery. Like remote operators of mega-trucks today.

Those robots could interact with the operators - driving into a "garage" that can be pressurized for maintenance, upgrades or science.

StarShip promises to reduce the cost of mass to orbit, making larger and more complex scientific, industrial and habitat options feasible.

If you want to look at someone that is further along on a concept like this you can look at SpinLaunch. Exactly what it sounds like with a gigantic centrifuge to spin and throw things really fast. But they are still throwing a small two-stage rocket.

https://www.spinlaunch.com/orbital

I think a reusable orbital tug which rendezvous with payloads is the play here. The tug would refuel from some of the gun-launched payloads.

I think it would probably have to refuel with every payload. Changing orbits that fast isn't cheap. It would be cool to see an analysis of this, I don't know if it would really make sense. I've seen some interviews with the space gun guys but unfortunately nobody really pressed them on this issue and they didn't mention any plans for space tugs.

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