I'm still very curious whether all these 50/60s space mega-plans could've. Could Orion have got hundreds on tons to Mars with the technology of it's time?
It's easy to be forgetful of what you could do analog electronics and with/out even primitive computers (The specs of some hand-made Tektronix equipment going back half a century are still well beyond what's in the hands on the hobbyist today) - some things require computers but some things are only made more efficient by them
The Saturn series might have been enlarged to a level (Nova) that would have been able to push a few hundred tons to Mars in a single launch. But it would have been a slow and super expensive (probably over $10B in today’s dollars for launch alone) trip, and it’s not clear if that’s enough mass to include a return vessel with enough fuel for any size crew.
Given the limitations of nuclear engines, in orbit refueling is the key to making deep space travel possible and affordable. Starship is going to weigh around 100 tons empty, carry around 100 tons of passengers and cargo, but will be over 1,000 tons fully fueled in low earth orbit.
That’s roughly four times the ship & payload that a Saturn V single launch could put into Mars intercept orbit, and Starship can reach Mars in half the time. And it’s cost could be as low as a few hundred million per Mars trip if performance goals are met, making it affordable to launch a fleet of dozens of Starships with hundreds of crews and thousands of tons of supplies and equipment every Synod.
To do this Starship has to show that
1) It can launch and relaunch quickly without a lot of expensive maintenance. Not necessary for Mars versions, but critical for tanker versions needed to fuel them.
2) That its thermal protection system can handle dozens of reentries at very high velocities, such as Mars Intercept speeds.
3) That it can be refueled in orbit, at a scale that has never been done before. Each Mars mission will require 8 tanker flights to top up.
4) That it can provide a robust long term life support system across the various temperature and vacuum levels to and on Mars that will work for years with only on site maintenance.
There are two types of radiation. Cosmic radiation you can't really do all that much about without making a much bigger more complex vehicle. The plan here is just to 'take it' and improve the speed of transit over time.
Solar radiation is only temporary and in such cases Starship will have a 'bunker' that has good shielding. Meaning is surrounded by water and food.
So long as we are talking about small crews that should be fine, large crews this needs to be thought threw more carefully.
For the actual Mars spaceship it will likely not have dozens of reentries, that would be 20+ years of operation. The tanker or simple commercial cargo version will need to handle dozens of earth reentries.
Otherwise I think your dead on with the challenges.
I think the major missing one is ice mining on mars. The life support for a relatively small crew should be manageable, you can have inefficiency thanks to the absurd size. Only once you want to put 100 people in it you need to be perfect on your life management efficiency.
I skipped ice mining because the missions don’t require it as a prerequisite.
The first teams on the first synod don’t have to succeed at it. They will learn what does and doesn' work. Each succeeding synod they will get closer till they finally succeed. Every synod they will get new supplies and better equipment to address the failings of the previous.
And if it takes too long, they will eventually get sent tankers to supply return trips.
Without Ice mining or some way of getting water you are stuck on Mars. Its absolutely part of the core requirement. Check Elon presentation from 2016, its in there as one of the key things.
It’s a core requirement for return flights to Earth in the “Mars Direct” model that SpaceX has based its plan on.
But the SpaceX plan doesn’t require the astronaut return on the first Synod, or on any fixed schedule. The first to land will have ice mining and in situ fuel generation equipment, but we have no idea if they will work, or work at a level that will generate enough fuel for return flights in reasonable time periods.
Which is fine. Succeeding missions will bring equipment to address the shortcomings of the first, until they are producing fuel effectively for return missions.
The first astronauts are unlikely to be able to return in the first two years, it might take ten. But they will happily sign up for this plan because it gets them to Mars decades sooner.
SpaceX plan is very, very, very different from "Mars Direct". It basically shares absolutely nothing of the architecture other then the idea that ISRU is important.
And what Mars direct, ie transporting hydrogen to mars, will absolutely not work for SpaceX.
> But the SpaceX plan doesn’t require the astronaut return on the first Synod, or on any fixed schedule.
Very unlikely that SpaceX or NASA would leave anybody there for two terms in a row.
I don’t think this can be overstated. Aerospace is notoriously expensive in large part because of its quality requirements. The amount of checks, oversight, buy-offs, traceability etc. adds enormous cost. Unfortunately, this risk increases over time because as more bad things happen there is a natural pull to add bureaucratic layers/checks to avoid the same thing happening again, eroding any previous maintenance/cost savings
Civilian space programs were glorified cover stories for ICBM programs.
The Apollo program was announced at a time when a lot of things had gone wrong, e.g. Bay of Pigs, so it was a political easy win.
Satellites were needed because those pesky Russians could shoot down the spy planes.
All the good peace loving stuff was facilitated by the Cold War imperative. The war was the main meal, peaceful things were garnish.
In some parallel peace loving alternative universe there are no countries or wars and the surplus capital is spent on space exploration. Sadly that is not our world. However, had we not spent all our silver on wars then we would have had the resources to get to Mars. The tech aspect of navigation and landing was achieved on the moon.
You also have to remember people got bored of space after a while. This audience wasn't regained until a generation later with early Shuttle launches. SpaceX launches are equally lucky to have a fresh audience in a new generation to be wowed. Interest wanes, politics is politics, resources get spent on war first, however, I don't question our collective ability to have got to Mars in the 1960's had we wished to.
The US had already transitioned to solid rocket ICBMs with the Minuteman and Polaris programs before the Apollo program even started. The military certainly benefited from advances and electronics from the program, but that R&D was a tiny fraction of the expenditures. No need to spend 4% of the National budget to justify that.
And there was no shot of getting to Mars in the 60s. The massive expenditure that Apollo required barely got us to the moon by the end of 1969.
Even the shuttle program was heavily influenced by military requirements. NASA would have had a vastly more capable program if it didn't have dual requirements
23 comments
[ 0.25 ms ] story [ 61.9 ms ] threadIt's easy to be forgetful of what you could do analog electronics and with/out even primitive computers (The specs of some hand-made Tektronix equipment going back half a century are still well beyond what's in the hands on the hobbyist today) - some things require computers but some things are only made more efficient by them
Yes, but having dangerously irradiated our own planet in the process
Given the limitations of nuclear engines, in orbit refueling is the key to making deep space travel possible and affordable. Starship is going to weigh around 100 tons empty, carry around 100 tons of passengers and cargo, but will be over 1,000 tons fully fueled in low earth orbit.
That’s roughly four times the ship & payload that a Saturn V single launch could put into Mars intercept orbit, and Starship can reach Mars in half the time. And it’s cost could be as low as a few hundred million per Mars trip if performance goals are met, making it affordable to launch a fleet of dozens of Starships with hundreds of crews and thousands of tons of supplies and equipment every Synod.
To do this Starship has to show that
1) It can launch and relaunch quickly without a lot of expensive maintenance. Not necessary for Mars versions, but critical for tanker versions needed to fuel them.
2) That its thermal protection system can handle dozens of reentries at very high velocities, such as Mars Intercept speeds.
3) That it can be refueled in orbit, at a scale that has never been done before. Each Mars mission will require 8 tanker flights to top up.
4) That it can provide a robust long term life support system across the various temperature and vacuum levels to and on Mars that will work for years with only on site maintenance.
Solar radiation is only temporary and in such cases Starship will have a 'bunker' that has good shielding. Meaning is surrounded by water and food.
So long as we are talking about small crews that should be fine, large crews this needs to be thought threw more carefully.
Otherwise I think your dead on with the challenges.
I think the major missing one is ice mining on mars. The life support for a relatively small crew should be manageable, you can have inefficiency thanks to the absurd size. Only once you want to put 100 people in it you need to be perfect on your life management efficiency.
The first teams on the first synod don’t have to succeed at it. They will learn what does and doesn' work. Each succeeding synod they will get closer till they finally succeed. Every synod they will get new supplies and better equipment to address the failings of the previous.
And if it takes too long, they will eventually get sent tankers to supply return trips.
But the SpaceX plan doesn’t require the astronaut return on the first Synod, or on any fixed schedule. The first to land will have ice mining and in situ fuel generation equipment, but we have no idea if they will work, or work at a level that will generate enough fuel for return flights in reasonable time periods.
Which is fine. Succeeding missions will bring equipment to address the shortcomings of the first, until they are producing fuel effectively for return missions.
The first astronauts are unlikely to be able to return in the first two years, it might take ten. But they will happily sign up for this plan because it gets them to Mars decades sooner.
And what Mars direct, ie transporting hydrogen to mars, will absolutely not work for SpaceX.
> But the SpaceX plan doesn’t require the astronaut return on the first Synod, or on any fixed schedule.
Very unlikely that SpaceX or NASA would leave anybody there for two terms in a row.
I don’t think this can be overstated. Aerospace is notoriously expensive in large part because of its quality requirements. The amount of checks, oversight, buy-offs, traceability etc. adds enormous cost. Unfortunately, this risk increases over time because as more bad things happen there is a natural pull to add bureaucratic layers/checks to avoid the same thing happening again, eroding any previous maintenance/cost savings
There existed another concept from that time frame:
[1] https://en.wikipedia.org/wiki/Sea_Dragon_(rocket)
Isn't that splashy ?
The Apollo program was announced at a time when a lot of things had gone wrong, e.g. Bay of Pigs, so it was a political easy win.
Satellites were needed because those pesky Russians could shoot down the spy planes.
All the good peace loving stuff was facilitated by the Cold War imperative. The war was the main meal, peaceful things were garnish.
In some parallel peace loving alternative universe there are no countries or wars and the surplus capital is spent on space exploration. Sadly that is not our world. However, had we not spent all our silver on wars then we would have had the resources to get to Mars. The tech aspect of navigation and landing was achieved on the moon.
You also have to remember people got bored of space after a while. This audience wasn't regained until a generation later with early Shuttle launches. SpaceX launches are equally lucky to have a fresh audience in a new generation to be wowed. Interest wanes, politics is politics, resources get spent on war first, however, I don't question our collective ability to have got to Mars in the 1960's had we wished to.
And there was no shot of getting to Mars in the 60s. The massive expenditure that Apollo required barely got us to the moon by the end of 1969.