Newtonian telescope secondary mirror. This design reduces the size and cost of the telescope with a shorter overall telescope tube length (with the corrector extending the focal length in a "telephoto" type layout) combined with a less costly spherical mirror. Commercially produced versions of this design have been noted to be optically compromised due to the difficulty of producing a correctly shaped sub-aperture corrector in a telescope targeted at the inexpensive end of the telescope market. Newtonian telescope The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir
Newtonian dynamics a separate symbol and then treated as independent variables. The quantities are used as internal coordinates of a point of the phase space formula_20 of the constrained Newtonian dynamical system. Geometrically, the vector-function () implements an embedding of the configuration space formula_18 of the constrained Newtonian dynamical system into the formula_29-dimensional flat comfiguration space of the unconstrained Newtonian dynamical system (). Due to this embedding the Euclidean structure of the ambient space induces the Riemannian metric onto the manifold formula_18. The components of the metric tensor of this induced metric are given by the formula where formula_31 is the scalar