SpaceX (general discussion)

[sferrin]

Take my cynicism as being more directed at the breathless coverage the Musk name gets in the UK (where Bezos is not even mentioned). You would think that only Musk could do these things. In the UK, the media dont talk about Falcon 9, they talk about hyperloop, flying to Sydney in half an hour and how Tesla are the only EV manufacturers.

I think a lot are just caught up in his acceptance of risk and stick-to-itiveness. Can you remotely imagine NASA or ULA saying, "our launch vehicle might not even make it to orbit. If it clears the launch area, I'll consider it a win." And now SpaceX has 16 landings under it's belt. It's a breath of fresh air in a world constantly bombarded by negativity from the media.

 

[mrmalaya]

Agreed.

 

[CJGibson]

Did Brunel ever deliver?

Great Western Railway - everything from locos to sheds
Clifton Suspension Bridge
Royal Albert Bridge
Box Tunnel (part of GWR)
Paddington Station (part of GWR)
SS Great Britain
SS Great Eastern
SS Great Western

I could go on. He did have some less successful ventures, such as the Atmospheric Railway and launching the SS Great Eastern, but he is generally considered the greatest engineer in Britain. By me anyway.

Might be worth watch if you don't know about Brunel:

https://www.youtube.com/watch?v=QwHnVH9jWmU

Chris

 

[sferrin]

Okay, thanks. Had never heard of him and thought maybe he was another Moller. :-[

 

[Flyaway]

Can SpaceX afford its new Mars rocket — and will there be a market for it?

https://www.theverge.com/2017/9/30/16384096/elon-musk-spacex-bfr-mars-rocket-development-business-demand

 

[NeilChapman]

Can SpaceX afford its new Mars rocket — and will there be a market for it?

https://www.theverge.com/2017/9/30/16384096/elon-musk-spacex-bfr-mars-rocket-development-business-demand

Good, critical, article.

Asks a good question.
Can SpaceX profitably use the BFR @ less than capacity?
How much are they banking on greenfield uses of BFR?
How much greenfield business is available if launch costs drop by 20%, 50%, 80%?
Is there a market for intra planet transport - same day, worldwide delivery?

I suspect SpaceX is saying, "We don't know."
What we do know is that there are opportunities that are not available to us with our current platforms.
We do know that we have a marketable vision to enable inter-planetary travel.
We do know our cost structure is markedly less than our competition.
We do know that we have a window of opportunity to add scale, capability and, potentially, increase margins.
We do know that nations, companies, universities and individuals would like to work in space but can't afford the price of access.
We do know that the US Government is concerned about the defense of its satellites.
We do know that space junk is a problem.

We also know that should our version of the 747 be useful for only several decades we can pivot to a 777 or 737 at will.

He has done a great job of communicating his vision. He obviously has a drive and passion to deliver which has encouraged others to invest in that vision.

Does that take away from anyone else? No
Does he have character flaws? Of course

PayPal, SpaceX and Tesla, three iconic brands since the year 2000. The first reinterpreted how people pay for products. The second seeks to reinterpreted how we interact with our universe by attempting to move access control from nations to individuals. The third has reinterpreted how we think about automotive transportation and has forever changed the industry.

The Boring company follows the same model. Identify a problem. Analyze solutions. Remove costs and focus on a particular usage by utilizing a system of systems that creates value for individuals.

Not bad for one guy and only 17 years.

 

[Grey Havoc]

I suspect that they will end up keeping Falcon Heavy after all is said and done; they are going to need the revenue from it (and then some!).

 

[greedo]

SpaceX believes the BFR will be cheaper to operate than a Falcon 9, so even if it flies at less than full capacity, it's still a net win.

 

[NeilChapman]

SpaceX believes the BFR will be cheaper to operate than a Falcon 9, so even if it flies at less than full capacity, it's still a net win.

I saw that as well - but - Musk wasn't clear whether it was cheaper per flight with reference to the load or not.

 

[FighterJock]

SpaceX believes the BFR will be cheaper to operate than a Falcon 9, so even if it flies at less than full capacity, it's still a net win.

I saw that as well - but - Musk wasn't clear whether it was cheaper per flight with reference to the load or not.

It will be interesting to see when BFR starts flying as to whether it is cheaper in the long run than an equivalent Falcon 9/Falcon Heavy launch.

 

[NeilChapman]

SpaceX believes the BFR will be cheaper to operate than a Falcon 9, so even if it flies at less than full capacity, it's still a net win.

I saw that as well - but - Musk wasn't clear whether it was cheaper per flight with reference to the load or not.

It will be interesting to see when BFR starts flying as to whether it is cheaper in the long run than an equivalent Falcon 9/Falcon Heavy launch.

Yes -

I guess what I was hearing was that...

when Engineering, Manufacturing and Development costs are included,
over the number of ships that are built,

BFR is cheaper.


The question is "How was that quantity identified?"

I suspect they've decided,
SpaceX needs X ships for their own Mars missions.

One or two EMD ships for testing - 2019-2021
Two ships for hauling gear to some TBD space port staging area. 2021
Two ships for 1st trip that will stay at Mars. 2022
Four ships for 2nd trip, if 1st trip successful. 2024

I'm at 10 before 2024 @ 150 tons of lift per ship. That's probably more lift capacity than all existing launches today. 2016 Orbital Launch Attempts - 85, with 22 each from US and China. If they were all on the largest lift rockets that's only ~1k tons. Ten BFR's is ~1.5k tons.

Interesting notes...

SpaceX will execute ~1/4 of all US launches this year (2017).
USAF alone is planning 48 launches next year - more than doubling USA launches.
NASA's SLS (Block 1 in production now) is supposed to be capable of carrying 150k-290K lbs to low earth orbit when fully developed (2029).
Hmmm, 300k lbs, sound familiar?
NASA's SLS is 8.4M in diameter
SpaceX BFR is 9M in diameter.
NASA has spent ~US2B upgrading the launch pad etc. at Kennedy Space Center for SLS - which BFR could make use of.
NASA has stated that manned Mars program is expected to cost ~US$400B.


NASA will fly SLS Block 1 ship in 2019. Block 1 = 77 ton lift capacity
Two rockets are in production today.
NASA will fly SLS Block 1B ship in 2022. Block 1B = 115 ton lift capacity
Block 1B is to utilize a more powerful 2nd stage.
NASA's next objective is SLS Block 2 in 2029. Block 2 = 143 ton lift capacity.

Way before then, 2022, SpaceX expects to be flying a 150 ton lift capacity - BFR.

Sounds like SpaceX wants to supplant the SLS Block 1B EMD effort - no? Congress will be saying, why are we spending X for Block 1B development when SpaceX can do it for less, today? Being the same size, BFR will be able to lift the components of the NASA Mars Transfer Vehicle to LEO. This could accelerate the NASA Mars program by years and save several billion of NASA's annual $19B budget.

Getting the transport piece (if not more) of that NASA Mars program $400B budget is what SpaceX is banking on. That's 'Program of Record' money. Way better than potential greenfield opportunities.

 

[Flyaway]

Elon Musk Ready To Bet It All On BFR

SpaceX founder and CEO Elon Musk says he has fixed a fatal flaw in the interplanetary space transportation system unveiled during last year’s International Astronautical Congress (IAC), namely, how to pay for it. The 46-year-old tech entrepreneur now plans to phase out his company’s successful Falcon rockets and Dragon capsules in favor of a reusable, two-stage, multipurpose super-heavy-lift launcher that not only can take on the satellite delivery and station resupply ...

http://m.aviationweek.com/space/elon-musk-ready-bet-it-all-bfr

 

[Michel Van]

News from Elon Musk on instagram and Tweet of Oktober 4, 2017.

Aiming for two rocket landings in 48 hours this weekend

October 7, KSC launch of SES-11 / EchoStar 105 This feature third flight of Falcon 9 "B1031.2"
October 9, VAFB launch of Iridium NEXT 21–30 satellites


Source:
https://www.instagram.com/p/BZzchfKg07f/

 

[FighterJock]

News from Elon Musk on instagram and Tweet of Oktober 4, 2017.

Aiming for two rocket landings in 48 hours this weekend

October 7, KSC launch of SES-11 / EchoStar 105 This feature third flight of Falcon 9 "B1031.2"
October 9, VAFB launch of Iridium NEXT 21–30 satellites


Source:
https://www.instagram.com/p/BZzchfKg07f/

Any word on timings for those launches yet Michel Van? Or is it too early.

 

[TomS]

News from Elon Musk on instagram and Tweet of Oktober 4, 2017.

Aiming for two rocket landings in 48 hours this weekend

October 7, KSC launch of SES-11 / EchoStar 105 This feature third flight of Falcon 9 "B1031.2"
October 9, VAFB launch of Iridium NEXT 21–30 satellites


Source:
https://www.instagram.com/p/BZzchfKg07f/

Any word on timings for those launches yet Michel Van? Or is it too early.

https://spaceflightnow.com/launch-schedule/

The launch window for SES-11 / EchoStar 105 is 2253-0053 GMT (6:53-8:53 p.m. EDT)
The launch time for Iridium NEXT is 1237 GMT (8:37 a.m. EDT; 5:37 a.m. PDT) [this is an instantaneous window]

 

[Flyaway]

I wish they would give BFR/BFS proper names.

 

[sferrin]

I wish they would give BFR/BFS proper names.

BFS? (Agreed, they do sound more than a bit juvenile.)

 

[Flyaway]

SpaceX delays Falcon 9 launch of TV broadcast satellite

SpaceX confirmed the delay in a tweet.

“The shift gives us extra time to complete final launch preps with the bonus of bypassing some bad weather headed for the Cape this weekend,” a SpaceX spokesperson said.

The company did not disclose a reason for the four-day slip, but one source said SpaceX needed to conduct some “minor engine rework” on the Falcon 9.

https://spaceflightnow.com/2017/10/05/spacex-delays-falcon-9-launch-of-tv-broadcast-satellite/

 

[FighterJock]

Is the other Falcon 9 launch going to go ahead?

 

[flanker]

Iridium Next Mission 3 - Oct 9
SES-11 (with a reflown booster) - Oct 11 (for now, might be bumped due to ULA)

 

[FighterJock]

Just found this interesting article about SpaceX's plans to colonise Mars by 2024.

https://futurism.com/elon-musk-plans-colonize-mars-overlook-major-hurdles/

 

[NeilChapman]

Just found this interesting article about SpaceX's plans to colonise Mars by 2024.

https://futurism.com/elon-musk-plans-colonize-mars-overlook-major-hurdles/

Engineers, in general, tend to discount these types of risks. They'd do better to get out in front of them.

 

[DWG]

I'd expect a significant proportion of the SpaceX Mars team to have either read or be familiar with KSR's Mars Trilogy (as mentioned in the article), it's the seminal work on Mars colonisation and the overall story arc is absolutely focused on the tensions between preservationists and terraformers, the reds and the greens. Obviously Musk seems to be in the green camp, but that doesn't mean there won't be people both inside his camp and outside of it who understand the need to deal with contamination issues - that's why we just crashed Cassini into Saturn, after all.

And ultimately SpaceX needs a license to operate.

 

[fredymac]

Getting so blase' I forgot all about this.

https://www.youtube.com/watch?v=M3nxMakbQ1E

 

[sferrin]

Getting so blase' I forgot all about this.

https://www.youtube.com/watch?v=M3nxMakbQ1E

And they landed it. 17th in a row now.

 

[Flyaway]

Iridium-3 Mission replay is now up:

https://www.youtube.com/watch?v=SB4N4xF2B2w

 

[FighterJock]

Iridium-3 Mission replay is now up:

https://www.youtube.com/watch?v=SB4N4xF2B2w

Thanks for posting the launch video Flyaway, I had forgot about it too.

 

[FighterJock]

Just so that you all know, SpaceX is launching the EchoStar 105 satellite on mission SES-11 in seven hours. They have a webcast page already set up the link is posted below.

http://www.spacex.com/webcast

 

[sferrin]

And another landing.

 

[fredymac]

I'm getting pretty good at forgetting these things.

https://www.youtube.com/watch?v=0HanPjRLLzE

 

[Flyaway]

Here’s the full launch webcast from Space X.

https://youtu.be/iv1zeGSvhIw

 

[Dragon029]

As promised on Twitter, Elon Musk did an AMA (Ask Me Anything) on Reddit; here's the Q&As:
https://www.reddit.com/r/space/comments/76e79c/i_am_elon_musk_ask_me_anything_about_bfr

[BFS = Spaceship / upper stage of BFR]

Q: Why was Raptor thrust reduced from ~300 tons-force to ~170 tons-force?
One would think that for (full-flow staged combustion...) rocket engines bigger is usually better: better surface-to-volume ratio, less friction, less heat flow to handle at boundaries, etc., which, combined with the target wet mass of the rocket defines a distinct 'optimum size' sweet spot where the sum of engines reaches the best thrust-to-weight ratio.
Yet Raptor's s/l thrust was reduced from last year's ~300 tons-force to ~170 tons-force, which change appears to be too large of a reduction to be solely dictated by optimum single engine TWR considerations.
What were the main factors that led to this change?

A:We chickened out
The engine thrust dropped roughly in proportion to the vehicle mass reduction from the first IAC talk. In order to be able to land the BF Ship with an engine failure at the worst possible moment, you have to have multiple engines. The difficulty of deep throttling an engine increases in a non-linear way, so 2:1 is fairly easy, but a deep 5:1 is very hard. Granularity is also a big factor. If you just have two engines that do everything, the engine complexity is much higher and, if one fails, you've lost half your power. Btw, we modified the BFS design since IAC to add a third medium area ratio Raptor engine partly for that reason (lose only 1/3 thrust in engine out) and allow landings with higher payload mass for the Earth to Earth transport function.

Q: Elon,
Does SpaceX have any interest in putting more satellites in orbit around Mars (or even rockets) for internet/communications before we get feet on the ground? Or are the current 5-6 active ones we have there sufficient?
Cheers

A: yes

[presumably he means yes to the former]

Q: Also will there be some form of an internet or communications link with Earth? Is SpaceX going to be in charge of putting this in or are you contracting some other companies?

A: If anyone wants to build a high bandwidth comm link to Mars, please do

Not exactly a question but:

Q: The concept of an internet connection on Mars is kinda awesome. You could theoretically make an internet protocol that would mirror a subset of the internet near Mars. A user would need to queue up the parts of the internet they wanted available and the servers would sync the relevant data.
There could be a standard format for pages to be Mars renderable since server-side communication is impractical.

A: Nerd
But, yes, it would make sense to strip the headers out and do a UDP-style feed with extreme compression and a CRC check to confirm the packet is good, then do a batch resend of the CRC-failed packets. Something like that. Earth to Mars is over 22 light-minutes at max distance.
3 light-minutes at closest distance. So you could Snapchat, I suppose. If that's a thing in the future.

Q: Will the BFS landing propellants have to be actively cooled on the long trip to Mars?
The BFS has header tanks to store landing propellants.
When traveling to Mars they will have to be stored for months. Heat transfer slowly but surely rises the temperature of the tanks, eventually boiling off the propellants.
Will liquid methane and LOX have to be cooled - or is thermal insulation of the header tanks expected to be so good that no active cooling is required?
If cooling is required, what kind of system will the BFS use to manage the temperature of propellants in zero-gee?

A: The main tanks will be vented to vacuum, the outside of the ship is well insulated (primarily for reentry heating) and the nose of the ship will be pointed mostly towards the sun, so very little heat is expected to reach the header tanks. That said, the propellant can be cooled either with a small amount of evaporation. Down the road, we might add a cryocooler.

Q: Will the BFS tanker ships (have to) do a hoverslam landing?
The BFS tanker ship appears to have a minimum TWR of ~1.3 when landing mostly empty:
If we plug the 2016 BFT/BFS dry mass ratio of 90t/150t = 60% into the 85t 2017 BFS dry mass we get an estimated dry mass of ~51 tons for the 2017 tanker ship.
The 2017 s/l Raptor thrust figures you announced are 1,700 kN, which is ~173 tons-force, which can be throttled down to 20% of maximum thrust - which is ~35 tons-force per engine.
You also indicated that two engines will be used for landing for redundancy (spooling one of them up in case of engine failure takes too much time, so both need to be running), and two engines generate a minimum thrust of ~70 tons-force.
That minimum thrust is significantly higher than the empty tanker ship dry mass of ~51 tons, giving a landing Thrust-to-Weight-Ratio of ~1.35 even with the initial Raptor thrust figures - i.e. requiring a hover-slam landing approach.
Is this dry mass estimate accurate, and will the tanker indeed (have to) perform a hover-slam when landing on Earth, or will it use some other technique?

A: Landing will not be a hoverslam, depending on what you mean by the "slam" part. Thrust to weight of 1.3 will feel quite gentle. The tanker will only feel the 0.3 part, as gravity cancels out the 1. Launch is also around 1.3 T/W, so it will look pretty much like a launch in reverse....

Q: Hey there Elon!
With the first two cargo missions scheduled to land on Mars in 2022, what kind of development progress can we expect to see from SpaceX in the next 5 or so years leading up to the maiden flight?
Will we see BFS hops or smaller test vehicles similar to Grasshopper/F9R-Dev? Facilities being built? Propellant plant testing? etc. etc.
Many thanks and good luck!

A: A lot
Yes, yes and yes
Will be starting with a full-scale Ship doing short hops of a few hundred kilometers altitude and lateral distance. Those are fairly easy on the vehicle, as no heat shield is needed, we can have a large amount of reserve propellant and don't need the high area ratio, deep space Raptor engines.
Next step will be doing orbital velocity Ship flights, which will need all of the above. Worth noting that BFS is capable of reaching orbit by itself with low payload, but having the BF Booster increases payload by more than an order of magnitude. Earth is the wrong planet for single stage to orbit. No problemo on Mars.

This next question wasn't answered directly by Elon, but by other users, with Musk then confirming their answer:

Q: Will the BFS landing propellants have to be actively cooled on the long trip to Mars?
The BFS has header tanks to store landing propellants.
When traveling to Mars they will have to be stored for months. Heat transfer slowly but surely rises the temperature of the tanks, eventually boiling off the propellants.
Will liquid methane and LOX have to be cooled - or is thermal insulation of the header tanks expected to be so good that no active cooling is required?
If cooling is required, what kind of system will the BFS use to manage the temperature of propellants in zero-gee?

Response question: Isn't Methane capable of remaining as a liquid if it's pressurized?

Other user's answer: Yes, but the pressure is extremely high. About 32 MPa/4600 psi, so the tank to hold that is way too heavy.

Elon: exactly

Q: Could you update us on the status of scaling up the Raptor prototype to the final size?
The sub-scale Raptor prototype has a (speculated) thrust of about ~100 tons-force currently, and will be scaled up to ~170 tons-force according to your IAC/2017 design.
Can you tell us more about the current status and expected (best-case) timeline of this scale-up effort?

A: Thrust scaling is the easy part. Very simple to scale the dev Raptor to 170 tons.
The flight engine design is much lighter and tighter, and is extremely focused on reliability. The objective is to meet or exceed passenger airline levels of safety. If our engine is even close to a jet engine in reliability, has a flak shield to protect against a rapid unscheduled disassembly and we have more engines than the typical two of most airliners, then exceeding airline safety should be possible.
That will be especially important for point to point journeys on Earth. The advantage of getting somewhere in 30 mins by rocket instead of 15 hours by plane will be negatively affected if "but also, you might die" is on the ticket.

Q: Will the BFS tanker's payload section be empty, or include extra propellant tanks?
You showed the BFS and the tanker in your slides at the 2017 AIC. In this CAD image the two ships have the exact same length and the exact same main tank layout.
It's not visible what's inside the tanker's payload section: will it be empty, or include extra propellant tanks?

A: At first, the tanker will just be a ship with no payload. Down the road, we will build a dedicated tanker that will have an extremely high full to empty mass ratio (warning: it will look kinda weird).

Q: Will the BFS heat shield be mounted on the skin, or embedded?
Will the BFS PICA-X heat shield be mounted on top of a common, single piece of 9m diameter cylindrical carbon-fiber outer tank skin additively, or will it be an integrated part of the outer BFS skin?

A: The heat shield plates will be mounted directly to the primary tank wall. That's the most mass efficient way to go. Don't want to build a box in box.

Q: Will the BFS methalox control thrusters be derived from Raptor or from SuperDraco engines?
The BFS will have methalox RCS thrusters for spaceship attitude control. (See the three dark dots at the bottom of the spaceship.)
Can you tell us more about these thrusters, will they have turbopumps (simplified Raptor engines?), or will they be pressure-fed from high pressure methalox reservoirs with no moving parts (SuperDraco engines modified for methalox) - or use some other design?

A: The control thrusters will be closer in design to the Raptor main chamber than SuperDraco and will be pressure-fed to enable lowest possible impulse bit (no turbopump spin delay).

Q: Will the BFR autogenous pressurization system be heat exchanger based?
You told us previously tha the BFR will eliminate the use of Helium and use hot oxygen and hot CH4 to auto-pressurize the propellant tanks.
Can you tell us more about this new system, will it involve heating the propellants at the engines via heat exchangers and routing the hot gas back to the tanks via pipes, or will they use some other method?
If it's heat exchanger based, will all Raptor engines have heat exchangers?

A: We plan to use the Incendio spell from Harry Potter: http://harrypotter.wikia.com/wiki/Fire-Making_Spell
But, yes and probably

Q: Will Raptor engines be (metal-) 3D printed?
The unprecedentedly high degree of integration between Raptor engine components has created speculation on /r/spacex to what extent the Raptor might be metal- 3D printed. SpaceX's SuperDraco engines are 100% 3D printed, so SpaceX has extensive experience with using 3D printing to build smaller scale rocket engines.
Do the benefits of 3D printing transfer to the Raptor scale as well, for example is it practical to 3D print the Raptor's main combustion chamber, or is casting+machining still the better technique?

A: Some parts of Raptor will be printed, but most of it will be machined forgings. We developed a new metal alloy for the oxygen pump that has both high strength at temperature and won't burn. Pretty much anything will burn in high pressure, hot, almost pure oxygen.

Q: Can the BFS delta wings and heat shield be removed for deep space missions?
In the BFS/2016 design the 'delta wings' were an integrated part of the main unibody BFS airframe.
The new BFS/2017 delta wings and heat shield appear to be additive components to the outer skin of the rocket.
Also, the BFS solar panels appear to be stored in the engine compartment close to the engines, not in the wings.
Was this (apparent) modularization done so that the delta wings and heat shield can be skipped during manufacturing, allowing lower dry mass expendable missions and deep space missions with no atmosphere at the destination - or are there other motivations as well?

A: Wouldn't call what BFS has a delta wing. It is quite small (and light) relative to the rest of the vehicle and is never actually used to generate lift in the way that an aircraft wing is used.
It's true purpose is to "balance out" the ship, ensuring that it doesn't enter engines first from orbit (that would be really bad), and provide pitch and yaw control during reentry.

[Elon did specifically call them delta wings at the 2017 IAC presentation, but evidentally means 'would no longer call it' a delta wing.]

Q: Why is the 2017 BFS spaceship largely cylindrical?
The 2016 ITS spaceship design had a complex geometrical shape with aerodynamic lifting/braking properties.
The new 2017 BFS design uses a largely cylindrical body, with a payload section and two delta wings attached. The diameter of the BFS is now the same 9m as the BFR booster.
Were these changes mainly prompted by a desire to unify the carbon-fiber manufacturing of the cylindrical sections of the BFR and the BFS on a shared 9 meter diameter manufacturing process, or are there other advantages to the new design as well?

A: Best mass ratio is achieved by not building a box in a box. The propellant tanks need to be cylindrical to be remotely mass efficient and they have to carry ascent load, so lowest mass solution is just to mount the heat shield plates directly to the tank wall.

Q: How does the BFS achieve vertical stabilization, without a tail?
The 2016 BFS spaceship design had a complex unibody geometrical shape with two 'wings' on the sides, a 'tail' protrusion on top, plus split body flaps at the bottom-end, which gave it a fair degree of aerodynamic control freedom. The Space Shuttle had delta wings and a tail too.
The new 2017 BFS spaceship has two delta wings, which gives it pitch and roll control, but does not have an airplane 'tail assembly' equivalent.
How is vertical stabilization achieved on the BFS?
Do the unusually thick (~2m tall) delta wings have vertical stabilization properties perhaps?

Elon: Tails are lame

Another user replying to the above question: The space shuttle's vertical stabilizer was completely useless for most of the reentry profile, as it was in complete aerodynamic shadow. I think it's clear a craft doesn't need one for reentry, only for subsonic gliding, which BFS doesn't really do.

Elon: +1

Q: Why was the number of BFS landing legs increased from 3 to 4?
The BFS/2016 design used three landing legs, while the new BFS/2017 design uses four.
What is the motivation behind this change?

A: Because 4
Improves stability in rough terrain

Q: Hello Elon,
Let me start by joining everyone else in thanking you for taking the time to do this AMA. My question(s) is regarding the first payloads on the cargo and human flights to Mars in the next 5-10 years.
Obviously there will be an extreme amount of care put into what is sent on the first missions, and the obvious answer of “Solar Panels” and “Fuel Production Equipment” is included, but what else?
Will you be sending food and water rations for early colonists? If so, enough rations to last how long? (100 Colonists for 1 Year, or 5 Colonists for 5 Years)
Side Note: Is there a unit of measurement for the above question based on observations by NASA or Russia, or is that something that you’ll be developing? (specific amount of mass) that is used. A standard for the calculations of “X mass of rations will allow Y number of humans to live in a spaceship or a spaceship like environment for Z units of time”
What type of autonomous machines to help prepare the landing/colony site will be onboard these early missions? Will they be in use prior to human arrival, or just sitting there waiting for the first colonists?
These seem like the types of things that SpaceX isn’t focused on, but some of the other industries you’re involved in are focused on directly or indirectly. (Boring, Tesla, etc.)
Follow up question - What companies are you working with to provide the technology that SpaceX isn’t focused on?

A: Our goal is get you there and ensure the basic infrastructure for propellant production and survival is in place. A rough analogy is that we are trying to build the equivalent of the transcontinental railway. A vast amount of industry will need to be built on Mars by many other companies and millions of people.

Q: Besides the "solar storm shelter", how is the radiation shielding in the ITS? Are you guys using part of the payload as shielding? Or is there a dedicated armor?

A: Ambient radiation damage is not significant for our transit times. Just need a solar storm shelter, which is a small part of the ship.
Buzz Aldrin is 87.

[Referring to Aldrin's time going in and out of Earth's magnetosphere during Apollo]

Q: Why was the location and shape of the BFS header/landing tanks changed?
In the 2016 BFS design the header tanks were spherical tanks with different diameters, embedded in their respective main tanks.
In the new 2017 BFS design the header tanks are both embedded in the CH4 tank, are both elongated, have the same diameter and same bulkhead and appear to be surrounded by a shared secondary tank skin as well.
What is the motivation behind these changes?

A: The aspiration by the change was to avoid/minimize plumbing hell, but we don't super love the current header tank/plumbing design. Further refinement is likely.

Q: IAC easter eggs: Does your Mars city feature permanently anchored BFS spaceships?
One of the slides of your 2017 IAC presentation is showing a beautiful overview of the future Mars city.
The city is surrounded by five landing pads with four spaceships on them, but interestingly it also appears to show two spaceships "embedded" in the city permanently: surrounded by buildings and unable to take off ever again without damaging nearby structures.
Does this mean that the first two spaceships that will bring a permanent crew to Mars will probably not return to Earth and will be used as the initial seed for the Mars city?
(Also, in that image there's a single building in the lower middle section of the Mars town, with a SpaceX logo on it. Is that your future home on Mars perhaps? )

A: Wouldn't read too much into that illustration

Q: Boring question about Mars:
You clearly like things that are boring, and you are also good at waiting for Godot!
Will the first BFS spaceship that lands on Mars carry a tunnel boring machine?
If yes, could it be used to mine water ice and minerals from the ~30,000 tons of excavated dirt per km of tunnel bored?

A: More boring!

Q: Can BFS vacuum-Raptors be fired at sea level pressure?
The BFS will have four Vacuum-Raptors and two sea-level Raptor engines, embedded in a protective skirt.
Will it be possible to start the vacuum Raptors at s/l pressure as well (with reduced efficiency due to over-expansion), for example in case of an emergency launch escape and landing event, or to allow a higher return payload mass than ~50 tons?
Or can they only ever be fired in low air pressure?

A: The "vacuum" or high area ratio Raptors can operate at full thrust at sea level. Not recommended.

[Other users mentioned that flow separation could cause nozzle damage, but that perhaps this might be a launch escape option]

Q: Who will design and build the ISRU system for the propellant depot, and how far along is it?

A: SpaceX. Design is pretty far along. It's a key part of the whole system.

[ISRU = In-Situ Resource Utilisation = O2 & CH4 extraction]

Q: Have any candidate landing sites for the Mars base been identified? Are you prioritising places with high scientific value, or high safety (e.g flat boulder-free plain)?

A: Landing site needs to be low altitude to maximize aero braking, be close to ice for propellant production and not have giant boulders. Closer to the equator is better too for solar power production and not freezing your ass off.

 

[Flyaway]

Over on NASA Spaceflight forum/Reddit its been noted that a mysterious payload called ZUMA has appeared on Space X’s launch schedule.

NET November 10, 2017 on Falcon 9 (booster 1043) from LC-39A. RTLS landing is expected.

Jeff Foust @jeff_foust
Replying to @Cosmic_Penguin
ZUMA is more likely to be a codename, not an acronym. But I’m sure you can come up with some creative retronyms…

https://mobile.twitter.com/jeff_foust/status/919594402439417856

 

[FighterJock]

Over on NASA Spaceflight forum/Reddit its been noted that a mysterious payload called ZUMA has appeared on Space X’s launch schedule.

NET November 10, 2017 on Falcon 9 (booster 1043) from LC-39A. RTLS landing is expected.

Jeff Foust @jeff_foust
Replying to @Cosmic_Penguin
ZUMA is more likely to be a codename, not an acronym. But I’m sure you can come up with some creative retronyms…

https://mobile.twitter.com/jeff_foust/status/919594402439417856

Very interesting Flyaway, no doubt we will hear more about what ZUMA is as launch day approaches.

 

[Michel Van]

Interesting

ZUMA could be part of US Activity started with PAN (2009) CLIO (2014)
Not much is know only they build by Lockheed Martin and launch into geostationary orbit, for an undisclosed U.S. government customer.

Last one is very unusual, because mostly the spy Satellite are label like "NROL-number" for National Reconnaissance Office.
also unusual is the purpose of ZUMA, spy Satellite are mostly in Polar orbit or geostationary orbit
but since SpaceX announced Return To Launch Site for Falcon 9 means this could be orbit similar to ISS
like launch of NROL-76 by SpaceX on May 1, 2017 or USAF OTV-5 (Boeing X-37) on September 7, 2017.

 

[Flyaway]

Here’s a Spaceflight Now article on ZUMA. As it says it is unlikely to be a GEO payload as it is a RTLS.

https://spaceflightnow.com/2017/10/14/regulatory-filings-suggest-spacex-plans-november-launch-with-mystery-payload/

 

[Flyaway]

More from the Reddit conversation:

[–]old_sellsword 1 point 15 hours ago
Was this contract something that happened recently, or has it been confirmed for a while but the public just didn’t know about it?

[–]ASTRALsunder 1 point 2 hours ago
That I do not know, my friend. I did not press my sources for more details. The extent of my knowledge is the flight is named ZUMA/Zuma and the NET is November 15th. Customer contract details and what kind of satellite I do not know. They just emphasized the on-time part of the launch, it would be out of 39A, and on a new booster.
My friends did say CRS-13's new NET is December 4th out of LC-40. SpaceX pitched the idea of a flown booster for CRS-13 to NASA and they will give them an answer in early November.

 

[Flyaway]

Good article covering Space X’s forthcoming launch schedule including the mysterious ZUMA payload.

https://www.nasaspaceflight.com/2017/10/spacex-zuma-iridium-4-aims-vandenberg-landing/

 

[Flyaway]

Further to the above article.

NASASpaceflight.com has confirmed that Northrop Grumman is the payload provider for Zuma through a commercial launch contract with SpaceX for a LEO satellite with a mission type labeled as "government" and a needed launch date range of 1-30 November 2017.

 

[Flyaway]

USAF Space Command General Backs Reusable Rockets

http://www.parabolicarc.com/2017/10/17/usaf-space-command-general-backs-reusable-rockets/