has any telescope been named after him?
Yes, Herschelian telescope.
William Herschel
This "front view" design has come to be called the Herschelian telescope.
how many globular clusters are in the milky way About 150 to 158 currently known what are these? It is a spherical collection of stars that orbits a galactic core. do they contain metal? It consists of Population II stars, to which astronomers refer to as heavier elements as metals and to the proportions of these elements as the metallicity. how the last term calculated? Astronomers use several different methods to describe and approximate metal abundances, depending on the available tools and the object of interest. who were among the observers of this collection of stars? Abraham Ihle and William Herschel. who was the second? Astronomer and composer of music.
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William Herschel [SEP] Herschel's telescopes
The concave mirror gathered more light than a lens, reflecting it onto a flat mirror at the end of the telescope for viewing. A smaller mirror could provide greater magnification and a larger field of view than a convex lens. Newton's first mirror was 1.3 inches in diameter; such mirrors were rarely more than 3 inches in diameter. Because of the poor reflectivity of mirrors made of speculum metal, Herschel eliminated the small diagonal mirror of a standard newtonian reflector from his design and tilted his primary mirror so he could view the formed image directly. This "front view" design has come to be called the Herschelian telescope.