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Shoemaker-Levy Comet Fragment 9 impacting Jupiter July 22 1994
Photo from Wikimedia Commons by NASA/JPL |
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Jupiter, showing the impact marks from fragments of Comet Shoemaker-Levy 9 in July 1994
Photo from Wikimedia Commons. Original by Hubbel Space Telescope Comet Team and NASA |
Because [gravity] will act to pull meteors, comets, and other space debris toward a planet, the effective cross-section for a planet to capture an object is larger than its geometrical cross-section. What is the size of this effective cross-section in terms of the physical qualities of the planet and the situation? What features of the impacting body is it independent of?
Solution
System:
point particle subject to [gravity] but moving with constant [angular momentum].
Interactions:
[Gravity].
Model:
XXXXX.
Approach:
Diagrammatic Representation
The Force Diagram of the Meteor approaching the Planet
Force Diagram of Meteor and Planet |
The [single-axis torque] about the center of the planet is zero, because the force of [gravity] acts along the same direction as the radius r. About this point, therefore, [angular momentum] is conserved.
Mathematical Representation
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