Newtonian reflector
Quick Summary
A Newtonian reflector is a type of reflecting telescope that uses a spherical or paraboloidal primary mirror to gather light. A flat mirror, set at a 45-degree angle, then reflects the light to a focus at the side of the telescope tube. This design, pioneered by Isaac Newton, avoids chromatic aberration, a distortion that occurs in refracting telescopes where light disperses into colors.12
The primary mirror, typically made of glass coated with aluminum, reflects light from celestial objects. The Newtonian design is popular among amateur telescope makers due to its effectiveness and relative simplicity. The light-gathering power of a telescope, crucial for observing faint objects, is determined by the diameter of its primary mirror.234
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