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Old 09-15-2021, 07:54 AM
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blackshire blackshire is offline
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Join Date: Jan 2009
Location: Fairbanks, Alaska
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Originally Posted by luke strawwalker
Hey how have you been, Blackshire?? Doing well I hope.

That was an interesting video. Just goes to show just how much we've learned about the solar system and planets in the decades since that film was made! Still thought Mercury was tidally locked to the Sun (it's not, it rotates in a 3:2 resonance with it's orbital period, which makes for some interesting possibilities when it comes to exoplanets that we would normally consider "tidally locked" since such resonances would seem to allow for the planet to actually rotate and avoid becoming "eyeball planets" they would be if completely tidally locked, making them much more habitable). Not much known about Venus either but the clouds and thick atmosphere and the surface temperature. Mars "greening" was a bit on the fanciful side, but still couldn't actually be "disproven" until later on, though most scientists of the time were leaning more toward the "cold dry" Mars model because the atmospheric density and composition was known to be thin carbon dioxide, not particularly amenable to life. The assessment of Jupiter was also a bit fanciful, as the concept of the Great Red Spot being clouds around some unseen high terrain below was highly unlikely. Saturn was pretty accurate given what was known then, including Titan and its atmosphere, but of course it would be decades before we knew much about Titan, where water is frozen and weathered away into "sand" and the lakes are made of liquified natural gas... As for the outer planets, virtually NOTHING was known about them at the time other than they were gas giants, which could be calculated from their gravitational effects on other planets (mass), size (volume) and therefore calculate the density, which would have showed them to be too light to be anything but gas and liquid with maybe small rocky/metal cores. Likewise with Pluto. Hence no need to go there in the video and 'show our ignorance' about them...

Later! OL J R
Thank you. Until this week, staying alive had (again) become a full-time job; as Erich Spehl, one of the LZ-129 Hindenburg's crewmen--a rigger, said from his hospital bed seconds before he died (dictating a telegram to his girlfriend), "Ich lebe!" ("I live!"). But as soon as it came, the swelling and weeping of flesh stopped--medicine has no explanation for why these changes occur.

My first thought was, "Why was Willy dressed like a dentist?" (He almost always dressed in a suit and tie in public , and in television and film appearances, as well as in his lectures; the all-male literary banqueting club he was a member of, the Trap Door Spiders: , also dressed that way.)

Yes, I noted the errors and "avoidances" in "A Trip to the Planets" (the return to Earth after visiting Saturn and Titan was also a production trick--"We don't have time" [which he also explained in terms of the long trip time ;-) ]). Patrick Moore wrote in his books that he never saw the greening of Mars, or the equator-ward "wave of darkening" that other observers saw moving south (or north) from each pole, in that hemisphere's spring. Also:

No one ever suspected that Titan's atmosphere would be *denser* than our own (its surface pressure is about 50% greater, ~22 psi), because only the methane showed up in spectrograms. Nitrogen is very "shy" about spectroscopically revealing its presence, and it makes up most of the Titanian atmosphere. The opposite sort of assumption was made about Mars (which strangely, also involved nitrogen's "spectroscopic shyness" [maybe Titan's greater distance, and spectroscope technology back then, were why])--that its atmosphere was about 10% as dense as ours but was mostly nitrogen, with about 1% of it being carbon dioxide (the often planet-wide dust storms suggested that density).

It was a shock when Mariner 4's radio occultation experiment revealed that Mars' atmosphere is less than 1% as dense as ours, and is only carbon dioxide (with only very minute traces of oxygen, ozone, methane, etc.). The dust can linger in the air because it is amazingly fine-grained, with tiny particles, and:

It was equally surprising that not only does Mercury rotate out of synchronization with the Sun, but Mercury--like the Moon--has ice in permanently-shadowed polar region craters. That was thought to be impossible, especially for Mercury.
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
All of my book proceeds go to the Northcote Heavy Horse Centre
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