John Couch Adams - The Leonids

The Leonids

The great meteor shower of November 1866 turned his attention to the Leonids, whose probable path and period had already been discussed and predicted by Hubert Anson Newton in 1864. Newton had asserted that the longitude of the ascending node, that marked where the shower would occur, was increasing and the problem of explaining this variation attracted some of Europe's leading astronomers.

Using a powerful and elaborate analysis, Adams ascertained that this cluster of meteors, which belongs to the solar system, traverses an elongated ellipse in 33.25 years, and is subject to definite perturbations from the larger planets, Jupiter, Saturn and Uranus. These results were published in 1867.

Some experts consider this Adams's most substantial achievement. His "definitive orbit" for the Leonids coincided with that of the comet 55P/Tempel-Tuttle and therefore suggested the, later widely accepted, close relationship between comets and meteors.