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| date | 2000-11-01:09:44 |
| Physics |
I saw two shooting stars while taking the kids out for Halloween, and Jan saw one when we were looking at the aurora the other day. That seems like an unusually high rate -- there's supposed to be a meteor shower in mid-November, and these may be the precursors of it. Meteor showers are the detritus of comets crossing the orbit of the Earth just as the Earth itself is coming along. Comets are mountains of rock and ice, falling around the sun, the most famous of which is Halley's. The one's we see have hugely elongated orbits which take them well into the outer reaches of the solar system before plunging back toward the center. Each time they pass the sun they boil off some of their substance, and their orbit changes a bit as jets of gas come spewing off the surface, acting like primitive rocket engines. After enough times 'round, either the water gets boiled away entirely, or they get disrupted by tidal forces, and all that remains is a cloud of dust and gravel that slowly spreads out as it continues around in the cometary orbit, being pushed and pulled by planetary tides, mostly from Jupiter. When such a cloud crosses paths with the Earth, we get a meteor storm: a flurry of sparks in the upper atmosphere as the stoney remains of the comet incinerate themselves against the air. Last night, the first shooting star I saw was typical -- a brief slash of sparkling flame across the sky, travelling roughly west to east. It was a streak, rather than a point, as the bit of dust vaporized and spread peices of itself behind. The second was completely atypical, unique in my limited experience. It was a solid point of light, moving at what looked to be about ten degrees from the vertical to the north-west. It covered about ten degrees of sky (the length of my thumb held at arms-length from my eye) in around 2 seconds, and didn't shed any sparks at all. It was like a stone falling from heaven. The strangeness was in the missing trail of sparks, which I presume means it was a grain of nickle-iron or something equally tough, that didn't disintegrate as it fell. Whatever it was, it was very beautiful, and lasted long enough that both kids got to see it, prompted by my sudden shouts of "Wow, look at that! Quick! Look!" |
| Reading |
Idylls of the King takes a sharp dive downward when it departs from knightly deeds of dering-do and gets mired in the morality of love. Lancelot loves the Queen. The Queen loves Lancelot. Arthur is the John Galt of ancient literature -- generic image of characterless perfection, impossible to love. The story would be a good deal better if Arthur actually had a role to play, rather than simply standing there like some symbol of an unredemptive Christ, who just rubs the other character's noses in their inability to live up to the ideal he represents. Christ was a man. Arthur is an automaton. |