Oort cloud

1950 Oort cloud

The book of science

Tom Sharp

Jan Oort cosmology

Oort cloud

Vast space

Butterfly effect

In addition to predicting the Oort cloud, Jan Oort discovered the galactic halo, calculated the center of the Milky Way, and was the first to find evidence for dark matter. Although Jan Oort predicted the existence of the Oort cloud in 1950, it has not yet been directly observed. Nevertheless, you should search the news this fall for Comet ISON, assumed to be a one-time visitor from the Oort Cloud.

See also in The book of science:

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