Surely I am not alone in thinking this: never has my opinion of billionaires been lower, in light of recent events.
The prime example, although there are so many to chose from, is (of course) Elon Musk. A peculiar man seeking to exercise immense power by proxy, having succeeded in helping get said proxy elected via his social media empire, dwindling though it may now be.
Yet if questioned, he would claim it is all in the interest of "making humanity multiplanetary", his perceived vital long term goal.
What is irking me at the moment, with the "gee whiz" factor of the recent Starship test flights (the most recent one featuring a gormless Trump in tow), is that the future technical challenges to doing anything especially useful with this rocket system seem so far below the public radar.
I mean, relying on both a booster and the enormous manned vehicle to land safely via retrorocket and guidance that are to work perfectly each time? The deadstick landing of the space shuttle had a worrying enough component of "everything has to go right", but at least if they got close to the ground but not near a runway, there was some chance of exit of the horizontally moving machine. Seems to me that there are going to no similar systems possible on Starship, because if there is going to be a major problem, it is more likely to be at the very last minute, with the rocket having no opportunity to align itself to allow a slower descent or an attitude to allow easy crew escape.
Sure, the landing system looks cool, and it's not great disaster if it doesn't work each time with the booster - although there is a very good chance of huge and expensive destruction of the landing pad and facilities. But the manned rocket? I reckon it will only take a couple of fatal accidents and people will leap from "that's so cool" to "you know, this is just inherently dangerous and can you really ever use such a system reliably enough for humans?"
And how many people are really following the development story close enough to realise that it's going to be an enormous problem getting the thing to the Moon, or Mars, because of the need for in-orbit refuelling?
Have a read of this lengthy article from earlier this year, pointing out that it seems already the system is heavier than expected, and noting the huge difference it makes to the whole re-fuelling idea:
“Currently, Flight 3 would be around 40-50 tons to orbit.”
To understand the significance of this statement, one only needs to review prior statements about Starship’s performance. Ever since Musk’s 2017 presentation, Starship’s estimated payload capacity has ranged between 100 and 150 tons to Low Earth Orbit (LEO). SpaceX’s official Starship Payload Users Guide clearly states that “At the baseline reusable design, Starship can deliver over 100 metric tons to LEO” [3]. For the past six years, Starship’s diameter, height, and propellant mixture have remained constant. The most straightforward interpretation of Musk’s comment is that the rocket is suffering from a 50% underperformance.....
The success or failure of the Human Landing System program will be decided by Starship’s payload capacity. Due to its high dry (unfueled) mass, Starship HLS cannot reach the Moon without first refueling in LEO. To complete the Artemis 3 mission, SpaceX must therefore implement orbital refueling on an unprecedented scale. Even on Earth, loading cryogenic propellants into a launch vehicle is no easy feat; if anything, this will be more difficult in space. Prior to every Artemis mission, a flotilla of reusable Starship tankers will transfer liquid oxygen and liquid methane to an orbiting propellant depot. The lunar lander will then launch, receive a full load of fuel and oxidizer from the depot, and continue onwards to the Moon.
The number of tanker flights which will be required to complete Artemis 3 is hotly debated. Estimates range from four [5] to nineteen [6] launches of propellant per lunar landing. Former NASA Administrator Mike Griffin recently noted that the probability of mission success is directly correlated with the number of launches in each refueling campaign [7]. For instance, it is reasonable to assume that each individual Starship launch, plus the subsequent propellant transfer operation, will have a 98% probability of success once the procedure is refined. If five tanker flights are required, the mission as a whole will succeed in 90% of scenarios. In contrast, if twenty launches are needed, that probability drops to just 67%.
The precise number of tanker flights depends on several variables, including the Starship launch rate and the rate at which cryogenic propellant boils off to space while the depot is in orbit. However, no parameter is more important than the vehicle’s payload capacity. If Starship’s payload mass grows, the number of tanker flights required to complete an Artemis mission will decrease. Conversely, a reduction in payload capacity will increase the number of propellant launches.
The current iteration of Starship can store 1,200 tons of liquid methane and liquid oxygen in its propellant tanks. Recent renderings suggest that the lunar lander will be slightly taller, with a propellant load of approximately 1,500 tons. If each tanker can deliver 100 tons of fuel to orbit as advertised, then it will take 15 flights to complete an Artemis mission. This number is large, but given SpaceX’s demonstrated ability to scale up to a high cadence of missions, it is not insurmountable in medium- to long-term timeframes.
However, if SpaceX is only able to launch 50 tons of propellant to orbit inside each Starship tanker, then it will need to launch the world’s largest rocket a staggering 30 times to refuel a single lunar lander. Two additional launches will be required to place the Starship HLS and the propellant depot into orbit. To make matters worse, this hypothetical manifest does not take boiloff into account. Even if NASA and SpaceX achieve their stated goal of a 6-day turnaround between Starship launches, it will take over half a year to stage all of the propellant in orbit. Several additional flights might be required to replace the oxygen and methane which are lost during this time period.
I know there has been some publicity about the extraordinary complicated system NASA has been planning all these years for a return to the Moon, but it seems to me not enough.
And it's all because making a large rocket land vertically looks cool.
Another irony about Musk - I mean, beyond the one where he thinks everyone should have lots of kids, yet seems like the most absent father possible to his own - is the recent discussion on Sabine Hossenfelder's channel about concerns that we are getting much closer to a making low earth orbit unuseable due to a Kessler syndrome disaster.
Given that Muck Musk is already cluttering up the orbits with Starlink (another example of something with a "cool" factor but on deeper consideration, we might be better off not using), the ultimate irony would be an exploding Starship in orbit, combined with his hundreds of his other satellites, making low Earth orbit pretty much impossible to safely traverse to get to Mars.
Here's the video:
I think there is a better than even chance that Musk will go down in history as leading humanity to disaster and/or expensive dead ends, rather than being the saviour he thinks he will be.
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