According to the most widely held astronomical model (the nebular hypothesis), new stars are born from massive clouds of dust and gas (aka a nebula) that experience gravitational collapse. The ...

Ever since man perceived that the solar system is a cohort of planets revolving around a central sun, at different distances but in the same direction and in almost the same plane, he has wondered how ...

THE literature of geology has grown so immense that no man can be familiar with all of it, particularly when it refers to another continent than one's own, yet it comes as a surprise to a Canadian to ...

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If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in ...