What both books get horribly wrong is what all such do: they vastly overestimate how quickly space travel would occur and they totally fail to predict automation, computers and the like. For example, von B has a Hubble-like space telescope floating in space: but to use it, you have to visit it. And you point it by hand1. For example: von B has an expedition to Mars... but not preceded by any robot probes. von B also has canals on Mars, but never mind, they are going to be part of the story, I can forgive him those.
Clark has his boyz head off from Earth for Mars, in a ship rather reminiscent of an English steamer, but I think stuffs up the orbital mechanics. After leaving the jolly old Earth behind, he is saddened when Earth eventually becomes invisible, blotted out by the solar corona. Because of course the path from Earth to Mars is outwards, and so Earth and the Sun will be in line. Oops. von B, by contrast, as you'd expect gets the orbital mechanics right - at least as far as I can tell - but goes wrong in my highlight, where he is explaining temperature maintenance in space (aside: very quaintly, his space station is powered by solar power... but by steam solar power: a mirror boils water, and the spokes of his space station wheel serve to condense it).
This is radiative physics, and somewhat reminiscent of The idealised greenhouse effect model and its enemies. The easy one first: a fully reflective sphere at all wavelengths with no conduction will neither absorb nor emit radiation, and so will maintain whatever temperature it starts with, whatever that might be; there is no "temperature of equilibrium" because there is no transfer to permit equilibriation. But a fully black sphere at all wavelengths (idealised to have a superconducting surface, unless you want to think about the temperature distribution) will not. It will have some equilibrium temperature; if you start it hotter it will cool down, if you start it colder it will warm up. This, incidentally, is from page 93. On page 94 we find the statement that a mirror-polished spaceship will simply retain it's temperature, which is much better, though slightly wrong, because of course the people inside and equipement will emit heat, so it will slowly warm up. So p 93 might be an oversight, or perhaps a translators error; but probably not, because the same error occurs just a little above my quote.
Update: it turns out that Martians exist. They live entirely underground, but their pumping of water from the poles is visible. They are entirely benevolent and more advanced than us, but in need of rejuvenation. There are some tedious dialogues about religion and stuff that I skipped. Despite being more advanced, the Earthmen learn nothing from them; in turn the Martians have at no point listened to Earth radio broadcasts. The return-to-Earth happens with no assistance from the advanced Martians, presumably because von B wanted to prove his point that it could be done.
1. Its also not in constant use. It seems to be available and unused whenever our heroes happen to want to look at it.
2. Also, his propellants are hydrazine and nitric acid. Failing to think of liquid oxygen is odd, I think. For propulsion, that is. There's liquid oxygen for cabin air.
3. Page 102: it turns out that the guidance for the ships will be calculated by giant electronic super-brains, and stored on thousands of magnetic tapes, which tapes will be carried aloft and run by hand through the ship's course-correction facilities. Though a super-special lightweight machine was also to be carried, capable of producing tapes en route.
4. There's also some stuff about nuking the Commies into submission, so cue Tom Lehrer.
Science fiction novels are stories, not prophecies, so it doesn't really make sense to call getting the timing wrong or failing to predict robots errors. These stories would be quite dull if Mars had already been extensively explored by robots - one reason it's hard to find good space operas today.
Perfectly reflecting surfaces don't and can't exist, but if they did they would still be heated by collisions with the solar wind - probably also not known when the book was written.
More realistic than Venus stories...
The most bizarre failure of vision of the First Men On X genre was that, absent communications satellites, none of the stories foresaw that the first Moon launch & landing would be televised
If you want Mars stories where you can find plenty of science and nonscience to critique, as well as a heck of a good read, I recommend the John Carter of Mars stories.
CIP, I must agree:
> call getting the timing wrong or failing to predict robots errors
Indeed, but I wasn't, though that might not be clear. Those are wrong but are kinda forgiveable. Though the fact that *everyone* got it wrong is I think interesting.
Solar wind: don't fail abstraction; from the context, it's clear that's not what he means.
TV: yes, the other thing these all get wrong is how in contact with Back Home they aren't.
1948 was before solar cells. Of course it was thermal solar.
Oxygen boils off. For the crew, this is a feature, get a steady supply. For propulsion, this is a real problem on long duration flights. Need to keep it cold enough not to vaporize. Or use something else. Apollo used "Aerozine 50 as fuel and nitrogen tetroxide (N2O4) as oxidizer"
Phil, in the 60's hydrazine derivatives and red fuming nitric acid were considered safe and sane because Werner & Co made much use of them in the '40's
OTOH, Hydrogen was still in the Hindenburg's shadow, and fluorine really was too scary to handle.
Hydrogen is a great fuel for a boost to orbit.
How might you keep it cold enough for long enough to get to Mars? 20 K at 1 atm
It's a matter of carrying < a> a cryo jacket full of LN2 around, which kills the specific impulse advantage for long missions
IS this perfectly mirrored spaceship you mention also so mirrored on the inside?
Anyone read the Mars trilogy (Red Mars, Blue Mars, Green Mars), by Kim Stanley Robinson, a saga about the terraforming of the planet over centuries?
I read the first one and it was ok, but did not grab me deep down. It was epic, and interesting, but then the characters are not very sympathetic, what can you do? This was a Mars being developed by state capitalism, but with socialism and environmentalism lurking ready to pounce.
Are the other two worth reading?
"1948 was before solar cells."
I don't think that's right Phil, or at least not before PV electricity. I need to go find the relevant section in Let It Shine. Clearly it was before practical solar cells - not sure that's good enough excuse for sci-fi though.
William blogs about books before finishing, while I intend to blog about books after finishing and don't do it. I've been meaning to blog about Let It Shine for 8 months, maybe I'll get around to it.
BTW, regarding automation, I'm unimpressed with Clarke's alleged invention of the communications satellite. I think his idea was to put a few switchboard operators in an orbiting can.
Photoelectric cells exist, because a primitive version is used in the telescopes.
Practical solar cells would be more precise.
As this was "hard science fiction", I would expect in 1948 that thermal solar would be used rather than solar cells. Scientifically accurate for the science of the day. Solar cells would have required magic materials in 1948. No magic is allowed in hard sci-fi.
Phil, although Si was not yet well enough purifired for transistors in 1948, zone refining was already around , so there woud have been nothing magic about polycrystalline silicon PV back then.
As Charles Fritts demonstrated a 1% efficent selenium on copper solar cell in 1881, it's surprizing that Jules Verne did't beat Picard fils to the punch by using the sun to power some of his fantastic flying machines, like the. Albatross in Robur the Conquerer
I haven't worked out the orbital mechanics either:
but then I am probably in the category of refusing to do the maths means I am doomed to talk nonsense.
FWIW "This maneuver was named after Walter Hohmann, the German scientist who published a description of it in his 1925 book Die Erreichbarkeit der Himmelskörper (The Attainability of Celestial Bodies)."
Published well before either of your two works of fiction: 1951 and published 2006 but written 1940s?
RS, have you read Charles Fritts papers on selenium cells?
I don't think selenium cells ever topped 1% efficiency before 1948. Got a source?
"In late February 1953, Chapin commenced his photovoltaic research. Placing a commercial selenium cell in sunlight, he recorded that the cell produced 4.9 watts per square meter. Its efficiency, the percentage of sunlight it could convert into electricity, was a little less than 0.5 percent."
Silicon was at roughly the same state in the 1940's as selenium cells were in 1881. A single silicon solar cell had been made in 1940 at Bell Labs, but Bell Labs didn't make another one for 13 years.
Perhaps perhaps someone could have written hard science fiction in 1948 about future solar power cells. But a rocket scientist? He wouldn't have the background in semiconductor physics.
Thermal solar was more than an order of magnitude more efficient than selenium cells, and more widely understandable. If trying to show how people might get to Mars, don't introduce unnecessary complications. Invent as little as possible. Using thermal solar made a lot of sense in 1948. Solar cells didn't in 1948. The world has changed.
I did not say the Fritts cells " ever topped 1% efficiency before 1948."
As he used seleinium coated copper with a translucent gold leaf front electode, copper selenide may have fomed the active PV junction.
>"but I think stuffs up the orbital mechanics. After leaving the jolly old Earth behind, he is saddened when Earth eventually becomes invisible, blotted out by the solar corona. Because of course the path from Earth to Mars is outwards, and so Earth and the Sun will be in line."
To minimise delta-v needed, probably start in eclipse cone which might be an issue for solar steam power. There are obvious ways around this if you don't need to minimise delta-v, high orbit before starting or crazy inclined orbit for where you want to go. Not sure if your spaceships use continuous power or a burst of chemical power and that might alter the following: Insight seems to get a little ahead of Earth making viewing Earth possible quite early in the journey but it isn't long before Earth catches up again which would make viewing Earth dangerous without some sophisticated masking technique. Somewhere approaching half way through the journey, Earth would again become visible but by then Mars would be becoming as close as Earth and it would be much more exciting getting better views of destination rather than diminishing views of Earth.
From having fantastic views of Earth in orbit, complete revolution in ~90 minutes, this suddenly changes to only seeing dark side of Earth and near 24 hours for a rotation and then on to becoming dangerous to try to look. Saddened seems a reasonable emotion to expect from views rapidly declining from fantastic to not being able to see Earth.
Anyway I am not sure about you being so sure that the orbital mechanics have been stuffed up. There does appear a bit of a problem with 'becomes invisible' rather than dangerous to try to look.
The pic is nice. Clarke's OM is, as I recall, really very vague - I'll have another look next weekend if I remember. By comparison, von B supplies full details.
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