The Search for a Planet beyond Neptune

  title={The Search for a Planet beyond Neptune},
  author={Morton Grosser},
  pages={163 - 183}
N February 18, 1930, an assistant of the Lowell Observatory at Flagstaff, Arizona, found two tiny images 3.5 mm. apart on a pair of plates he was examining in a blink microscope. The dots were the photographic records of a moving object; their separation indicated that it was very distant, beyond the orbit of Neptune. The object was Pluto, the ninth planet of the solar system, and in finding it Clyde Tombaugh accomplished what his predecessors had been trying to do for more than eighty years… Expand
The planet nine hypothesis
Over the course of the past two decades, observational surveys have unveiled the intricate orbital structure of the Kuiper Belt, a field of icy bodies orbiting the Sun beyond Neptune. In addition toExpand
Measurement-based perturbation theory and differential equation parameter estimation for high-precision high-resolution reconstruction of the Earth's gravitational field from satellite tracking measurements
  • P. Xu
  • Physics, Geology
  • 2016
The numerical integration method has been routinely used to produce global standard gravitational models from satellite tracking measurements of CHAMP/GRACE types. It is implemented by solving theExpand
Measurement-based perturbation theory and differential equation parameter estimation with applications to satellite gravimetry
  • P. Xu
  • Mathematics, Geology
  • Commun. Nonlinear Sci. Numer. Simul.
  • 2018
Bearing in mind that satellite orbits can now be tracked almost continuously at unprecedented accuracy, the measurement-based perturbation theory is proposed and global uniformly convergent solutions to the Newton’s nonlinear governing differential equations of satellite motion for the next generation of global gravitational models are derived. Expand
Popper, Refutation and 'Avoidance' of Refutation
Popper's account of refutation is the linchpin of his famous view that the method of science is the method of conjecture and refutation. This thesis critically examines his account of refutation, andExpand
A Complete Bibliography of Publications in Isis, 1960{1969
Aborigenes [78]. according [155]. Action [39, 72]. actuelle [87]. actuelles [107, 84]. Acvaghosa [8]. Aegypten [30]. Aether [126]. Agnes [42]. al [11]. Albert [45]. alcune [51]. Algerien [30]. allaExpand


The Discovery of 58 Reaves , Gibson , " Kourganoff ' s contribu - Pluto , " Monthly Notices of the Royal Astro - tions to the history of the discovery of Pluto
  • 1931