Quote#Nature
The phenomena prove that the tail of a comet is vapour from its head…
Quote byDavid Gregory · 1659–1708
Commonly attributed — not confirmed in an authoritative edition. Cited on Wikiquote to: Inaugural Lecture by David Gregory M.D. Savilian Professor of Astronomy (1692).
English (original)
The phenomena prove that the tail of a comet is vapour from its head which, when the comet is greatly heated in the neighbourhood of the sun in perihelion, continually rises up and moves away into the regions opposite the sun.
— David Gregory
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