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We present here a new algorithm which enables the identification of stars in astronomical photographs using readily available star catalogs for this purpose. The algorithm was implemented in a stand-alone application called `Skyprint` capable of performing a matching process. The computational aspect of the problem can be designated to the wide class of image recognition methods and analysis of multidimensional data. The astronomical aspect concentrates on astrometry – the method of determining the coordinates of stars in the celestial sphere. The problem of identifying star patterns occurs most often in such areas as cosmic probe navigation, adjusting and merging numerous photographs of the sky together, or in recovering missing information in relation to a fragment of the sky represented in the photograph. [ABSTRACT FROM AUTHOR]

Einstein was motivated by a deep philosophical need, the quest for simplicity and unity in nature, to formulate and develop the theory of general relativity. He was not guided by a desire to confirm or interpret any particular experimental result(s) although he was aware of the need for experimental confirmation. Experiments are fundamental to modern physics: progress in physics is driven by experimental verification and no assumption can be taken seriously unless it can be tested experimentally. This is the only way to distinguish physics from metaphysics. Galileo repeatedly stressed this and his experiments in the sixteenth century were able to overthrow the 2000-year reign of the speculative laws of nature proposed by Aristotle. Today a theory without experimental verification has no value. Unfortunately general relativity, unlike its contemporary, quantum theory, does not have a secure experimental foundation. Einstein had shown that the perihelion shift of Mercury could be explained by general relativity with remarkable accuracy. He also proposed the gravitational redshift and the bending of light rays as two further tests of general relativity. Gravitational redshift was too small to be observed with the technology of the first half of the twentieth century. Also, as will be discussed later, this is really a test of the equivalence principle and not of the full theory of general relativity. The bending of light was measured in 1919 but the accuracy of the data was low and not sufficient to discriminate between general relativity and the alternative theories of gravity proposed in the 1960s. Similarly, there was considerable uncertainty, until recently, about the oblateness of the Sun which affects the perihelion shift of Mercury. Remarkably only one new test of general relativity has been proposed since the formulation of the theory by Einstein. [ABSTRACT FROM AUTHOR]

For 200 years, from the beginning of the eighteenth century to the beginning of the twentieth century, Newtonian mechanics reigned supreme. By the late nineteenth century, the few simple laws of Newtonian physics could explain, with uncanny accuracy, most of the disparate phenomena of the natural world. Everything in the heavens and on Earth appeared to obey the laws, and the mastery of these laws was bringing mankind the mastery of the environment. These laws dominated the way both scientists and laypersons thought. Newtonian mechanics has a deterministic framework for the cosmos and this was deeply satisfying to the Judeo-Christian culture of Western Europe. There were those who questioned Newton's assumptions of absolute space and time, independent of man, but anyone doubting the validity of the laws of motion or gravitation was not taken seriously by the scientific community. Newton had applied his theory of gravitation to two-body systems, such as the Sun and a planet. In the eighteenth century various attempts were made to extend it to three gravitating bodies. In 1682 Halley had claimed that the comet then observed in the sky had also appeared in 1531 and 1607; given, then, that the period of the comet was about 75 years, he predicted that it would reappear in 1758. Months before its appearance, the French mathematician Alexis Clairaut used tedious and brute-force mathematics to calculate the gravitational perturbations of Jupiter and Saturn on the otherwise elliptical orbit of Comet Halley. [ABSTRACT FROM AUTHOR]