Newcomb: "At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature, that it has not been proved to be inconsistent with any fact, that it is almost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun's heat, but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation.
Newcomb, Popular Astronomy; Lick Observatory publications.
Newcomb, was used from 1882 to 'goo; and since then the value 8.80" has been employed, having been adopted at a Paris conference in 1896.1 Five fundamentally different methods of determining the distance of the sun have been worked out and applied.
From an investigation of all the observations upon Mercury and the other three interior planets, Simon Newcomb found it almost out of the question that any such mass of matter could exist without changing either the figure of the sun itself or the motion of the planes of the orbits of either Mercury or Venus.
Newcomb found an excess of motions in the perihelion of Mars amounting to about 5" per century.
Newcomb A= 18 h Io m D = +31 ° 3 J.
Seeliger, who investigated this ratio for the stars of the Bonn Durchmusterung and Southern Durchmusterung, came to the conclusion (as summarized by Simon Newcomb) that for these stars the ratio ranges from 3.85 to 3.28, the former value being found for regions near the Milky Way and the latter for regions near the galactic poles.
SIMON NEWCOMB (1835-1909), American astronomer, was born in Wallace, Nova Scotia, on the 12th of March 1835.
In view of the wide extent and importance of his labours, the variety of subjects of which he treats, ard the unity of purpose which guided him throughout, Simon Newcomb must be considered as one of the most distinguished astronomers of his time.
The formation of the tables of a planet has been described by Cayley as " the culminating achievement of astronomy," but the gigantic task which Newcomb laid out for himself, and which he carried on for more than twenty years, was the building up, on an absolutely homogeneous basis, of the theory and tables of the whole planetary system.
In 1866 Newcomb had published' an important memoir on the orbit of Neptune, which was followed in 1873 by a similar investigation of the orbit of Uranus.
Completed one important section of the work projected by Newcomb in 1877.
Newcomb showed that this belief was unfounded, and that as a matter of fact the moon was falling rapidly behind the tabular positions.
Equatorial at the United States Naval Observatory, Newcomb devoted it almost exclusively for the first two years to observations of the satellites of Uranus and Neptune, being of opinion that it was better to do one thing well than many things indifferently.
As early as 1860 Newcomb communicated an important memoir to the American Academy, 4 On the Secular Variations and Mutual Relation of the Orbits of the Asteroids, in which he discussed the two principal hypotheses to account for the origin of these bodies - one, that they are the shattered fragments of a single planet (Olbers' hypothesis), the other, that they have been formed by the breaking up of a revolving ring of nebulous matter.
At the international conference, which met at Paris in 1896 for the purpose of elaborating a common system of constants and fundamental stars to be employed in the various national ephemerides, Newcomb took a leading part, and at its suggestion undertook the task of determining a definite value of the constant of precession, and of 1 Lionville, t.
Professor Newcomb, who has compiled an instructive table of the equinoxes severally observed by Hipparchus and Ptolemy, with their errors deduced from Leverrier's solar tables, finds palpable evidence that the discrepancies between the two series were artificially reconciled on the basis of a year 6 m too long, adopted by Ptolemy on trust from his predecessor.
Newcomb, Researches on the Motion of the Moon, Washington Observations for 1875, Appendix ii.
Not less comprehensive has been the work carried out by Professor Newcomb of raising to a higher grade of perfection, and reducing to a uniform standard, all the theories and constants of the solar system.
Leverrier, in 1858, calculated a value of 8.95" for the solar parallax (equivalent to a distance of 91,000,000 m.) from the " parallactic inequality " of the moon; Professor Newcomb, using other forms of the gravitational method, derived in 1895 a parallax of 8.76".
The rate of light-transmission was accordingly made the subject of an elaborate set of experiments by Professor Newcomb in 1880-1882; and the result, taken in connexion with the aberration-constant as determined at Pulkowa, yielded a solar parallax of 8.79", or a distance (in round numbers) of 93,000,000 m.
C. Kapteyn and Simon Newcomb, to estimate, through the analysis of their proper motions, the " mean parallax " of stars assorted by magnitude.
Newcomb in 1898 at a point about 4° S.
It was therefore surprising when, in 1877, Simon Newcomb found, by a study of the lunar eclipses handed down by Ptolemy and those observed by the Arabians - data much more reliable than the vague accounts of ancient solar eclipses - that the actual apparent acceleration was only about 8.3".
But this action has been recently worked up with such completeness of detail by Radau, Newcomb and Brown, that the possibility of any unknown term seems out of the question.
Newcomb, " Researches on the Motion of the Moon " (Appendix to Washington Observations for 1875, discussion of the moon's mean motion); S.
Newcomb, " Transformation of Hansen's Lunar Theory," Ast.
Newcomb, " Action of the Planets on the Moon," Ast.
A transparent atmosphere and clear horizon are necessary, conditions which can best be secured on a mountain top. The visibility of a light corresponding to the inference was shown by Simon Newcomb, by observations at the top of the Brienzer Rothorn, in 1905.
Yet more conclusive are the observations of Maxwell Hall at Jamaica, who reached conclusions identical with those of Barnard and Newcomb, from observations of the base of the light at the close of twilight, which he estimated at 60° in the line through the sun.
0[900); Maxwell Hall, U.S. Monthly Weather Review (March 1906); Newcomb, Astrophysical Journal (1905) ii.