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Did you say space lasers? https://m.youtube.com/watch?v=ykL-iMtpV50

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We are still far from figuring this out in detail, but the current plan is: 1. Send Dragon scouting missions, initially just to make sure we know how to land without adding a crater and then to figure out the best way to get water for the CH4/O2 Sabatier Reaction. 2. Heart of Gold spaceship flies to Mars loaded only with equipment to build the propellant plant. 3. First crewed mission with equipment to build rudimentary base and complete the propellant plant. 4. Try to double the number of flights with each Earth-Mars orbital rendezvous, which is every 26 months, until the city can grow by itself.

Initially, glass panes with carbon fiber frames to build geodesic domes on the surface, plus a lot of miner/tunneling droids. With the latter, you can build out a huge amount of pressurized space for industrial operations and leave the glass domes for green living space.

It used to be developing a new metal alloy that is extremely resistant to oxidation for the hot oxygen-rich turbopump, which is operating at insane pressure to feed a 300 bar main chamber. Anything that can burn, will burn. We seem to have that under control, as the Raptor turbopump didn't show erosion in the test firings, but there is still room for optimization. Biggest question right now is sealing the carbon fiber tanks against cryo propellant with hot autogenous pressurization. The oxygen tank also has an oxidation risk problem as it is pressurized with pure, hot oxygen. Will almost certainly need to apply an inert layer of some kind. Hopefully, something that can be sprayed. If need be, will use thin sheets of invar welded together on the inside.

Not sure that we've really mastered anything yet. Maybe starting engines...

I think we need a new name. ITS just isn't working. I'm using BFR and BFS for the rocket and spaceship, which is fine internally, but... Will aim to release details of the habitation section when we have actual live mockups. Maybe in a year or two.

Probably just pack the pressurized space with cargo. Early missions will be heavily weighted towards cargo. First crewed mission would have about a dozen people, as the goal will be to build out and troubleshoot the propellant plant and Mars Base Alpha power system.

- Approx 360 sec vacuum Isp and 290 metric tons of thrust - A high acceleration landing is a lot more efficient, so there wouldn't be any hovering unless it encountered a problem or unexpected wind conditions. A rocket that lands slowly is wasting a lot of fuel. - Aiming for 20 g's

The spaceship would be limited to around 5 g's nominal, but able to take peak loads 2 to 3 times higher without breaking up. Booster would be nominal of 20 and maybe 30 to 40 without breaking up.

Good question -- that wasn't shown at IAC. The spaceship and tanker would have split body flaps for pitch and roll. Probably just use the attitude control thrusters for yaw.

Yeah, for those that know their stuff, that was really the big news :) The flight tank will actually be slightly longer than the development tank shown, but the same diameter. That was built with latest and greatest carbon fiber prepreg. In theory, it should hold cryogenic propellant without leaking and without a sealing linker. Early tests are promising. Will take it up to 2/3 of burst pressure on an ocean barge in the coming weeks.

The big booster will have an easier time of things than Falcon, as the mass ratio of the stages is lower and it will have lower density. Net result is that it won't come in quite as hot and fast as Falcon, so Falcon should be a bounding case on the big booster. Final Falcon 9 has a lot of minor refinements that collectively are important, but uprated thrust and improved legs are the most significant. Actually, I think the F9 boosters could be used almost indefinitely, so long as there is scheduled maintenance and careful inspections. Falcon 9 Block 5 -- the final version in the series -- is the one that has the most performance and is designed for easy reuse, so it just makes sense to focus on that long term and retire the earlier versions. Block 5 starts production in about 3 months and initial flight is in 6 to 8 months, so there isn't much point in ground testing Block 3 or 4 much beyond a few reflights.

Those are the header tanks that contain the landing propellant. They are separate in order to have greater insulation and minimize boil-off, avoid sloshing on entry and not have to press up the whole main tank.

The liquid oxygen transfer tube serves as the header tank for ox

It had to be 42 for important scientific and fictional reasons! The dense packing is just to max out thrust to weight, but it would be cool if there was a virtual nozzle side effect.

yes

Yes, but probably only a few hours Party at Cocoa Beach!

Thrust to weight is optimizing for a surprisingly low thrust level, even when accounting for the added mass of plumbing and structure for many engines. Looks like a little over 230 metric tons (~500 klbf) of thrust per engine, but we will have a lot of them :)

1. Yes, the Falcon Heavy center core is seriously hauling a** at stage separation. We can bring it back to the launch site, but the boost back penalty is significant. If we also have to do the plane change for geo missions from Cape inclination (28.5 deg) to equatorial, then a downrange platform landing is needed. 2. The Mars transport system will be a completely new architecture. Am hoping to present that towards the end of this year. Good thing we didn't do it sooner, as we have learned a huge amount from Falcon and Dragon. 3. Our spacesuit design is finally coming together and will also be unveiled later this year. We are putting a lot of effort into design esthetics, not just utility. It needs to both look like a 21st century spacesuit and work well. Really difficult to achieve both.

Goal is 100 metric tons of useful payload to the surface of Mars. This obviously requires a very big spaceship and booster system.

At first, I was thinking we would just scale up Falcon Heavy, but it looks like it probably makes more sense just to have a single monster boost stage.

Yeah, they were great

Default plan is to have a sea level and vacuum version of Raptor, much like Merlin. Since the booster and spaceship will both have multiple engines, we don't have to have fundamentally different designs. This plan might change.

It won't look like other cars

Mostly gravity. The center of gravity is pretty low for the booster, as all the engines and residual propellant is at the bottom. We are going to weld steel shoes over the landing feet as a precautionary measure.

I pretty much made that up. I have no idea :) The grid fins are super important for landing with precision. The aerodynamic forces are way too strong for the nitrogen thrusters. In particular, achieving pitch trim is hopeless. Our atmosphere is like molasses at Mach 4!

If you want to get to orbit or beyond, go with pure rockets. It is not like Von Braun and Korolev didn't know about airplanes and they were really smart dudes.

The timeframe is not immediate, but we should be concerned. There needs to be a lot more work on AI safety. And, with all due respect to the Roomba dude, that is not a concern https://www.youtube.com/watch?v=Of2HU3LGdbo

Actually, we could make the 2nd stage of Falcon reusable and still have significant payload on Falcon Heavy, but I think our engineering resources are better spent moving on to the Mars system. MCT will have meaningfully higher specific impulse engines: 380 vs 345 vac Isp. For those unfamiliar, in the rocket world, that is a super gigantic difference for stages of roughly equivalent mass ratio (mass full to mass empty).

I do kinda feel like my head is full! My context switching penalty is high and my process isolation is not what it used to be. Frankly, though, I think most people can learn a lot more than they think they can. They sell themselves short without trying. One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to.

I actually measured this with my phone! Almost exactly 6 hours on average.

Kerbal is awesome!

Kerbal Space Program!

The best teacher I ever had was my elementary school principal. Our math teacher quit for some reason and he decided to sub in himself for math and accelerate the syllabus by a year. We had to work like the house was on fire for the first half of the lesson and do extra homework, but then we got to hear stories of when he was a soldier in WWII. If you didn't do the work, you didn't get to hear the stories. Everybody did the work.

There is no meaningful limit. We would have to replace a few parts that experience thermal stress after 40 cycles, but the rest of the engine would be fine.

With sub-cooled propellant, I think we can get the Falcon 9 upper stage mass ratio (excluding payload) to somewhere between 25 and 30. Another way of saying that is the upper stage would be close to 97% propellant by mass.

Showering

SR-71 Hard to pick a favorite. I tend to like FPS with a story, like Bioshock, Fallout or Mass Effect, but was also a big fan of Civ and Warcraft. French and BBQ Whiskey

Good school

There should definitely be a science mission to Europa

There is a great quote by Churchill: "If you're going through hell, keep going."

Unlikely