From a score of well-observed original orbits it is shown that the "new" long-period comets generally come from regions between about 50000 and 150000 A. U. distance. The sun must be surrounded by a general cloud of comets with a radius of this order, containing about 1011 comets of observable size; the total mass of the cloud is estimated to be of the order of 1/10 to 1/100 of that of the earth. Through the action of the stars fresh comets are continually being carried from this cloud into the vicinity of the sun. (Jan Oort)

From a score of well-observed original orbits it is shown that the "new" long-period comets generally come from regions between about 50000 and 150000 A. U. distance. The sun must be surrounded by a general cloud of comets with a radius of this order, containing about 1011 comets of observable size; the total mass of the cloud is estimated to be of the order of 1/10 to 1/100 of that of the earth. Through the action of the stars fresh comets are continually being carried from this cloud into the vicinity of the sun.

Jan Oort

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action carry cloud containing distance earth fresh general mass observable order original radius score show size sun total vicinity 100 regions stars

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