Added 1 new A* page:I saw the movie "Apollo 13" over the weekend! Yeah I know I'm like 15 years late on this. Anyway I quite liked it, although boy did they really make everything REALLY DRAMATIC. :o
If you can remember back through the years to when you saw the movie, in one of the early space scenes they're trying to maneuver or something and everyone starts shouting that the ship is getting close to "gimbal lock." They kept saying "gimbal" over and over in that scene, so I had to go look it up today. Turns out that a gimbal is just a freely rotating ring, like the three you put together, one inside the other, to make a gyroscope:
image by Stéphane Magnenat (source)
(^That's an 1867 replica of Foucault's 1852 gyroscope.)
So gimbal lock is when a ring rotates so it's flush with the ring on which it's mounted--at that point, the gyroscope has effectively lost a rotation axis; it isn't physically stuck really, but it can't adjust freely along one of its axes from that position, which can interrupt whatever someone was trying to do with the gyroscope; in the Apollo missions, they were important parts of the system that told the pilots and controllers which way the ship was oriented--so I *guess* if you hit a "gimbal lock" point as you're maneuvering around, the smooth tracking or orientation is lost as the gyroscope has to snap itself around and get back on track.
A brush with gimbal lock had also occurred with the Apollo 11 Command Module, just a few hours after the Lunar Module had landed on the Moon; Command Module pilot Mike Collins had to maneuver out of it (if gimbal lock had occurred, the ship's tracking system would have been disrupted, and Collins would have had to re-orient manually, ie without computer assistance), and then said jokingly to Mission Control "How about sending me a fourth gimbal for Christmas." Mounting a fourth gimbal inside the third gimbal of a gyroscope was the mechanical way to avoid gimbal lock; NASA hadn't wanted to add a fourth gimbal, apparently for cost and development reasons (instead they'd come up with an extensive document of procedures for avoiding gimbal lock), although earlier missions such as Gemini had had a fourth gimbal.
Nowadays of course if you're really high tech you don't have those troublesome gimbal things in your ship at all, but other fancier stuff I understand even less!
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I followed a link over the weekend to this old article on self-publishing by "Cerberus" comic author Dave Sim, and I noticed he said "The cliche (which isn't a cliche, it's the truth) is that you have two thousand bad pages in you and until you draw them, you won't start producing good pages." Well I added up the pages of all my comics and what do you know, I'm up to about 1,850 or so. Soon I'll be able to start producing good pages--this is exciting! :D
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