-"A Tragedy of Errors," p. 494.
This, of course, is part of the no-heavy-metals theme.
How can such a small planet have air and water?
-copied from here.
Lacking scientific knowledge, I thought that the point of the question was that a very small planet would lack a gravitational field strong enough to hold an atmosphere and hydrosphere but how does any planet generate such -spheres in the first place? Air and water are outgassed by tectonic processes and vulcanism which in turn result from the formation of a core which requires a gravitational field strong enough to squeeze iron, nickel etc into compact quantum states.
In the case of Nike:
Nike is very small but holds an atmosphere and biosphere because it is so old that its weak gravity has had enough time to pull heavier elements into an atmosphere-generating solid core. Age explains its sun's variability which adversely affects Nikean weather.
-copied from here.
Age also explains the lack of metals which were fused in earlier stars and became part of the composition of later planetary systems.
3 comments:
Kaor, Paul!
I also thought of Krasna and Altai, another very ancient sun and planet, seen in "A Message in Secret."
Ad astra! Sean
I helped disassemble a barn in the Ottawa Valley in Canada in the 1960's, one that was built in the 1840's, and there wasn't a nail or spike in the frame -- all yard-thick white pine timbers, some of them 120 feet long, hand-adzed, and then held together with oak treenails (pegs) securing mortise-and-tenon joints.
The whole thing was metal-less but strong as iron, sound as the day it was put up. We eventually had to cut the timbers off at ground level with chainsaws and then pull it over with a cable from a bulldozer.
(The municipality was putting a parking lot in there. My family salvaged the timber and build another, smaller barn on our property with the wood, which would otherwise have been burned.)
Kaor, Mr. Stirling!
Not only was that barn made from marvelous virgin old growth forest lumber, it was built with what I can only call amazing skill. True, in 1840 many metal products were probably too expensive for many people, putting a premium on methods not requiring the use of iron nails.
Ad astra! Sean
Post a Comment