On Mars, a man:
"...weighed about three-eighths of what he would have weighed on Earth." (p. 89)
Less than half: I had not realized that the difference was that great. This is why ERB thought that John Carter would be able to leap-frog over a twelve-foot green Martian and decapitate him with a single sweep of a sword. (See Mars, Lost And Found.) However, ERB has the Lunar "Kalkars" conquering Earth and not being weighed down by Terrestrial gravity. Poul Anderson never shows his Lunarians visiting Earth and they cannot tolerate as much acceleration as Terrans. Mars is the only place where both Terrans and Lunarians can live comfortably without taking any extra measures. On the Moon, Terrans can live comfortably if they regularly exercise in a centrifuge and Terran women must give birth in the higher gravity of the orbiting Habitat.
Rereading this novel, I want to hurry ahead to Guthrie at Proserpina but meanwhile the narrative presents detailed future historical information about conditions in the inner Solar System.
12 comments:
Kaor, Paul!
Problem is, we don't even YET know if genetically unmodified human women would not be able to complete pregnancies on the Moon. So, while Anderson's speculations on how the low gravity of the Moon might cause problems for pregnant women, that has not yet been proven to be the case.
And we should have known the answers to such questions before Anderson started writing the HARVEST books! Alas, the Great Stagnation preventing a real space program from founding colonies on the Moon set in after 1973. Because of dreamers like Elon Musk we might finally find out the answers to such questions!
Ad astra! Sean
Though strictly speaking the Kalkars don't live -on- the Moon; they live -in- the Moon, which is hollow and the interior has an atmosphere and, somehow, gravity, as Pellucidar does inside Earth.
That is right about the Kalkars. ERBian cosmology is extraordinary. Pellucidarian and inner-Lunarian "gravity" is supposed to come from centrifugal force.
Kaor, Paul and Mr. Stirling!
Both: But I thought Sir Isaac Newton satisfactorily explained what gravity is and how it works. So, Edgar Rice Burroughs should have drawn on Newton's work.
Ad astra! Sean
Sean,
But centrifugal force can simulate gravity inside a rotating cylinder or, presumably also, a spinning hollow globe.
Paul.
Kaor, Paul!
And that kind of centrifugal force simulating gravity inside a rotating cylinder is exactly what I hope will be built off Earth, in O'Neill habitats. But I simply can't gag down spinning hollow globes beneath the surface of Earth!
Ad astra! Sean
Sean,
ERB's idea was that the whole Earth is a hollow sphere with people living on the inside, a small sun at the center.
Paul.
Kaor, Paul!
ERB was a talented and natural born story teller, which means he was able to persuade readers to set aside any doubts they had about such fantasies while reading his stories. Even scientificially informed readers a century ago.
Ad astra! Sean
You could use spin and a few other things to simulate gravity within a hollow sphere.
(Note, it's a bit more than a simulation. We 'feel' gravity because a surface interrupts the force drawing us 'down'. Likewise, centrifugal force throws you 'out', but you feel it because something interrupts the motion. If the hollow object is big enough that you don't notice the effects of Coriolis forces on your inner ear, it's indistinguishable.)
With a tube-dash-cylinder, it's easy; the centrifugal force is uniform over the interior.
With a sphere, the problem would be that it would be greatest at the equator, and fade off to nothing at the poles.
There's a way around this; attach large spheres or half-spheres to the poles; better still if they're ultra-dense (collapsed matter or something of that sort), but it would work with ordinary matter too.
That way, if you juggle the factors correctly, you get uniform 'gravitation' all over the inside of the sphere.
If there had been a third book in the SKY PEOPLE/COURTS OF THE CRIMSON KINGS series I was going to use this for a Dyson Sphere-sized "Pellucidar", as the Venus and Mars were equivalents of their Golden Age pulp equivalents, so would this.
Kaor, Mr. Stirling!
Fascinating comments! Straight out of O'Neill's THE HIGH FRONTIER or the speculations of Freeman Dyson. I hope some of these speculative constructs are actually built.
Ad astra! Sean
See RINGWORLD by Larry Niven and ORBITSVILLE by Bob Shaw.
Kaor, Paul!
It's been a long time, but I think I read Niven's RINGWORLD, but not the Shaw book.
Ad astra! Sean
Post a Comment