"To determine the orbit of a heavenly body, without any hypothetical assumption, from observations not embracing a great period of time, and not allowing a selection with a view to the application of special methods, was almost wholly neglected up to the beginning of the present century; or, at least, not treated by any one in a manner worthy of its importance; since it assuredly commended itself to mathematicians by its difficulty and elegance, even if its great utility in practice were not apparent. An opinion had universal prevailed that a complete determination from observations embracing a short period of time was impossible."

--Carl F. Gauss, from the introduction to his 1809 Theory of the Motion of the Heavenly Bodies Moving About the Sun in Conic Sections (Charles Henry Davis transl., p. xiv)