I doubt it will happen. I expect a rocket with 1-2 Raptor engines to replace the Falcon 9 Heavy but not this. I know Elon has mentioned it but I think Falcon 9 Heavy is about as big as you can make a rocket without becoming uneconomic. Maybe you can use something twice the size but I think it is doubtful you can make a business case for it.
I am highly skeptical of Mars first architectures especially those without ISRU. Plus there are plenty of other options for the second stage that do not involve nuclear like solar thermal or solar electric which have higher ISP.
1-2 Raptors make no sense, you cannot easily re-use that. A reusable single-core 5 Raptor is about as small as you can get and do the Falcon 9 type recovery with a single engine. As I understand it, the Raptor is staged-combustion and can throttle down lower than the Merlin can as a percentage.
That would likely give you a single 6-7 Meter core stage, perhaps a single core would be a reusable 50 ton and a triple a reusable 100 ton or so.
To me, that would be the intermediate step to pursue before you commit to the BFR, it would still give you a reusable vehicle with 80% the payload of a Saturn V and being fully reusable, would be economically viable in its single core design.
I don’t see any economical Mars colony that doesn’t use orbital assembly, ISRU, and propellant depots both in LEO and low Mars orbit. With them, you don’t need a bigger rocket than F9H. The only one of the three he mentions is ISRU.
I agree. I also think that to open up the inner solar system we need to have a comprehensive exploration of nearby celestial bodies including the Moon and maybe Phobos or Deimos. The Mars Direct plans always seem like crap to me.
The main questions is always what can we do to startup an economy there. The propellant depots is one idea but we need to figure out some viable businesses too. While making transportation cheaper would help a lot I haven’t seen a lot of ideas for how to monetize this. There was talk at one point about mining since the metal prices were so high but they have come down recently so I don’t know if it still makes sense if it ever did.
Rockets are fun, but It also would be interesting to see a discussion of the long-duration autonomous life support systems of the sort MCT will need. AFAIK, those don’t exist at present and would have to be developed — by SpaceX?
It’s all about mass. BFR really does not make sense. Refuel in LEO instead. He speculates BFR cost $243m. I put BFR+MCT at $500m so we seem to mostly agree. Also, I don’t like how he presents his numbers which I think confuse some issues (you can figure out MCT dry mass, but it’s a pain.)
You don’t even need a FH (but should for economic reasons.) Replace the upper stage of an F9R with a 13T refuelable (LEO & Mars surface) to send a dozen crew at a time. Multiples of this configuration gives you the same capacity as MCT at a lower cost.
0.4/person/half a year with water recycling may be possible. I’ve been using 1T w/o recycling for an 8 mo one way trip.
The main difference is I don’t see the MCT landing (although I understand this has always been Elon’s intent.) If it can, it removes the cost of separate landers being met in mars orbit.
I doubt it will happen. I expect a rocket with 1-2 Raptor engines to replace the Falcon 9 Heavy but not this. I know Elon has mentioned it but I think Falcon 9 Heavy is about as big as you can make a rocket without becoming uneconomic. Maybe you can use something twice the size but I think it is doubtful you can make a business case for it.
I am highly skeptical of Mars first architectures especially those without ISRU. Plus there are plenty of other options for the second stage that do not involve nuclear like solar thermal or solar electric which have higher ISP.
1-2 Raptors make no sense, you cannot easily re-use that. A reusable single-core 5 Raptor is about as small as you can get and do the Falcon 9 type recovery with a single engine. As I understand it, the Raptor is staged-combustion and can throttle down lower than the Merlin can as a percentage.
That would likely give you a single 6-7 Meter core stage, perhaps a single core would be a reusable 50 ton and a triple a reusable 100 ton or so.
To me, that would be the intermediate step to pursue before you commit to the BFR, it would still give you a reusable vehicle with 80% the payload of a Saturn V and being fully reusable, would be economically viable in its single core design.
I don’t see any economical Mars colony that doesn’t use orbital assembly, ISRU, and propellant depots both in LEO and low Mars orbit. With them, you don’t need a bigger rocket than F9H. The only one of the three he mentions is ISRU.
I agree. I also think that to open up the inner solar system we need to have a comprehensive exploration of nearby celestial bodies including the Moon and maybe Phobos or Deimos. The Mars Direct plans always seem like crap to me.
The main questions is always what can we do to startup an economy there. The propellant depots is one idea but we need to figure out some viable businesses too. While making transportation cheaper would help a lot I haven’t seen a lot of ideas for how to monetize this. There was talk at one point about mining since the metal prices were so high but they have come down recently so I don’t know if it still makes sense if it ever did.
Rockets are fun, but It also would be interesting to see a discussion of the long-duration autonomous life support systems of the sort MCT will need. AFAIK, those don’t exist at present and would have to be developed — by SpaceX?
It’s all about mass. BFR really does not make sense. Refuel in LEO instead. He speculates BFR cost $243m. I put BFR+MCT at $500m so we seem to mostly agree. Also, I don’t like how he presents his numbers which I think confuse some issues (you can figure out MCT dry mass, but it’s a pain.)
You don’t even need a FH (but should for economic reasons.) Replace the upper stage of an F9R with a 13T refuelable (LEO & Mars surface) to send a dozen crew at a time. Multiples of this configuration gives you the same capacity as MCT at a lower cost.
0.4/person/half a year with water recycling may be possible. I’ve been using 1T w/o recycling for an 8 mo one way trip.
The main difference is I don’t see the MCT landing (although I understand this has always been Elon’s intent.) If it can, it removes the cost of separate landers being met in mars orbit.