Bud Brewster
Galactic Fleet Admiral (site admin)
Joined: 14 Dec 2013
Posts: 17082
Location: North Carolina
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 Posted: Fri Apr 22, 2022 12:56 pm Post subject: FEATURED THREADS for 4-22-22 |
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I disproved a members assertion that air friction on meteors was a "common misconception carried with us throughout life from old wives' tales fed to us in childhood". 
Then I disproved the misconception the Id monster's weight bent down the metal steps on the C-57-D.
And finally I defended the James Bond film that had the strongest element of science fiction.
Come on, guys, it's easy to find things to post about. Just find something I wrote the you don't agree with and then show me that I'm wrong.
I'd rather lose a debate that not debate at all. Please, challenge me about something! I once debated with Gord Green for three weeks about which side of Morbius' house this matte shot was showing! 
And we STILL don't agree! (But we had a ball, and we're still friends.)
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This Island Earth (1955)
| orzel-w wrote: | | Bud Brewster wrote: | | If the ship's hull was just being superheated by the air friction... |
Common misconception carried with us throughout life from old wives' tales fed to us in childhood. It's not friction from the air, but rather compression of the air that heats up bodies traveling faster than sound. You can make (or buy) fire starters that work on the same principle. |
Well now, there seems to be two schools of thought on that subject. 
A site called How Stuff Works agrees with you.
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When the meteor hits the atmosphere, the air in front of it compresses incredibly quickly. When a gas is compressed, its temperature rises. This causes the meteor to heat up so much that it glows.
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However, I was surprised by what the Nation Geographic site says!
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When a meteoroid enters the Earth’s upper atmosphere, it heats up due to friction from the air.
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And the NASA webisite called Space Place concurs with this.
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The meteors make it through the exosphere and thermosphere without much trouble because those layers don't have much air. But when they hit the mesosphere, there are enough gases to cause friction and create heat.
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But wait a minute! The Harvard Center for Astrophysic sides with you, too! 
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When a meteoroid (small asteroid) enters the atmosphere, it compresses the air in front of it. That compression heats the air, which in turn heats the object, causing it to glow and vaporize.
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This is mighty curious, because the two reputable sites that say friction is the cause of meteors burning up — both NASA and National Geographic — ought to know what they're talking about!
Wow, now I honestly don't know what to think! We all know that friction does cause heat, but I'm also convinced that compressed gases cause exactly what the two other sites describe.
Ah-ha . . . here's a thought. Perhaps BOTH of those situations are true! 
I can't think of any reason why the compressed, super-heated gas would not AlSO cause friction against the surface of the meteor. Could that be the reason we're getting two different answers?
I Googled the question "Which causes meteors to burn up: friction or gas compression?" and here's what I learned from a site called Stack Exchange in their section called Physics.
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Question: When an object (like a meteor) falls through the atmosphere towards the Earth, why does it start to heat up and glow? Is it because of the compressed air in front of it or because of drag?
Answer: It is both.
The air compressed in front of an object entering the atmosphere generates heat. This causes a loss of kinetic energy in the object which is a form of drag.
Meteors are moving very fast when they enter the Earth's atmosphere. The frictional forces generated by the collisions with molecules of the atmosphere are responsible for the heating.
Friction and especially compression of the air in front with the air heats up the meteor . . .
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And so, Wayne, with all due respect to you, the notion that friction burns up meteors is actually NOT just a "common misconception carried with us throughout life from old wives' tales fed to us in childhood."
Ah well, live and learn, eh?  [/size]
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Forbidden Planet (1956)
Did you watch the YouTube video and see the brief moments in which the flexible steps on the stairway actually "unbend" during that scene?
I've always been baffled by the way we're supposed to see the steps bending . . . and then see later on that they are NOT bent . . . and then, with repeated viewings of the movie, notice that they UNbend in the finale moments of that shot!
All this seems to represent mistakes in the concept (the monster is so heavy it bends the metal steps), and a mistake in the continuity (later scenes show that the steps were NOT bent), and a mistake in editing (the steps bend down . . . but then we see them come back UP!)
Read the first part of page 76 of the script and you'll see that Cyril Hume describes the scene very differently than it was shot in the movie. [/size]]
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Moonraker (1979)
I'm not a fan of the Roger Moore films in the Bond franchise, but I was really impressed by the space battle in the climax. The special effects are still gorgeous, as shown by the video below.
_________ Moonraker 1979 - Laser Battle scene
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And then Bond and Miss Goodhead chase the last remaining poison gas container in a space shuttle equipped with a laser, skipping across the atmosphere, causing the shuttle to heat up.
Very dramatic.
____________ Moonraker - Attempting Re-Entry
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Is there no man on Earth who has the wisdom and innocence of a child?
~ The Space Children (1958) |
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