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0

At re-entry speeds, ablative cooling dissipates heat much more efficiently than "liquid cooling" because it first efficiently absorbs the heat into a phase change and then quickly moves the heated (vaporized) parts of the heat shield elsewhere. Liquid cooling of the heat shield doesn't address where to move the heat of the warmed liquid. Even if the liquid ...


4

I think it’s because they want to use the same pipe work they use for tanking on the ground in orbit. I imagine the Starship will have an LOX inlet/outlet on one side and a Methane inlet/outlet on the other and all Starship will be built in the same way. If you back one Starship onto another with the heatshields pointing in the same direction the LOX pipe ...


2

As other answers have pointed out, the necessary noise is much lower for landing than take off, but this doesn't mean that the actual amount of noise will be so reduced. As control theory gets better, and landing on a larger fraction of the available thrust becomes an option, I think we will see it happen as it makes sense from a performance point of view. ...


3

During the Q&A after the September 2019 updated, one of the media reporters asked Elon what the time line was for the test. He replied saying in 1 to 2 months to do the 20km flight with mark 1. I don't remember seeing October 11 anywhere. There seems to be no paperwork that's is public yet about any kind of hop. They will have to file a Temporary Flight ...


3

Another take on the question: you have to get your aiming perfectly right. Others have already pointed out, that landing does not cause as much noise as launching. However, if we consider using a sound suppression system, then this comes along with a lot of plumbing and other infrastructure. For launch, this is not a problem, since the location of the ...


3

TLDR A landing booster creates < 10% of the noise of a rocket launch. This is possibly reduced much further in near vacuum conditions (Moon/Mars). No sound suppression could be fine at these noise levels. To expand on the previous answer; A rocket's engines must create more force than the force of gravity on the rocket in order for it to accelerate ...


7

The amount of energy involved in a take off and landing will be roughly equal to the mass being moved, and approximately the same proportion of energy will be turned into sound given the same engines are involved. Going up a falcon heavy is around 1400 tonnes, coming down the stages have split apart and are almost empty. Have not found authoritative numbers ...


37

In my experience, I've noticed that SpaceX uses a lot of temporary components until such temporary components need to actually be tested. Since the legs of MK1, MK2, and most probably MK3 will never see uneven soils rather than concrete landing pads, they will most likely just have simple legs. After a few successes with MK3, we should start seeing much more ...


12

Quick answer is all I have time for now -- if someone wants to do a more detailed and referenced answer, please feel free and I'll delete this: While it's very big, its mass is not that high, and gravity is low. On Mars, for instance, it needs about 150 tons of fuel, plus 100 or so tons of vehicle (mass) to get back to orbit. Under Mars gravity thats only ...


1

Starship minus Super Heavy cannot reach orbit, but with extra Raptors fitted, it should be able to achieve hops of up to 10,000 km. https://www.teslarati.com/spacex-elon-musk-wants-starship-spaceliners/


2

It would seem elementary to be able to move cargo out of the ship, but it is a technical problem of moving and storage. It occurred to me that besides having a modified gantry lift and automatic machinery as a main moving mechanism, there needs to be manual mechanics to be a backup system. Also, since gravity is so low perhaps a circular slide filled with ...


5

No, not from Earth. According to Elon Musk's most recent comments at SpaceX's 2019 Starship Update presentation, Starship cannot reach orbit without the Super Heavy first stage booster, at least on Earth. (Though when launching from the moon or Mars it's no problem.) Previously in 2018 Musk had stated on Twitter that Starship would be technically capable ...


7

This has been answered before, but I chose not to just mark it a duplicate because there is one new reason for the header tank unique to Starship. In a Reddit AMA in 2017 where Elon Musk answered questions about the original ITS design, he answered a question about the header tanks: Those are the header tanks that contain the landing propellant. They are ...


8

SpaceX has implied that there will be a crew/cargo lift system similar to how skyscraper window washing platforms work (a crane swings the platform out from inside and lowers it to the ground): SpaceX teased it at the end of this video from last year:


4

The design hasn't been confirmed publicly by SpaceX yet, but probably some kind of elevator. One of the mockup drawings showed Starship having a stowed crane for offloading cargo, so it wouldn't be unreasonable to assume they could stick a flat platform with handrails on that. Picture at 33s into the video:


3

A partial answer: according to Garret Erin Reisman, professor of astronautical engineering and former SpaceX human spaceflight developer, the current state of knowledge is that you can get around a loss of bone mass almost entirely by proper exercise. The key to this is that bone loss is basically an issue of a lack of stimulation, and not a lack of ...


2

According to The Man Himself Raceway & flap hinge aero covers More here, more speculative. Doesn't match current planned configuration?


3

How will Starship ... accommodate micro-gravity? As of today, it won't. Making non-micro gravity by spinning about its long axis is impractical because the ship's radius is only 15 feet. Others have made detailed calculations for spinning about other axes. This is the kind of thing that helps SpaceX cultivate its bonkers-but-works reputation, but SpaceX ...


2

Difficult to know for sure, as with all things Musk, but likely it's similar to the shuttle Fibrous Refractory Composite Insulation (FRCI) tiles. The FRCI tiles are a high strength tile derived by adding AB312 (alumina-borosilicate fiber), called Nextel, to the pure silica tile slurry. These tiles are developed by the 3M Company of St. Paul, Minn....


2

NASA released a manual control requirements white paper for the Integrated Human Lunar Lander (IHLL) as part of their Appendix H Broad Agency Announcement (BAA). It can be found here: https://www.fbo.gov/notices/5491073942d867e576fbb1acc32bb8d2 as Attachment A17. I found it to be an interesting read and it covers manual control actions during different ...


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