The periods of revolution of colored stars present
the greatest differences; thus, in some instances, the period extends to 43
years, as in ??pi of Corona, and in others to several thousands,, as in 66
of Cetus, 38 of Gemini, and 100 of Pisces. Since Herschel's measurements in
1782, the satellite of the nearest star in the triple system of [Greek
letter] of Cancer has completed more than one entire revolution. By a
skillful combination of the altered distances and angles of position,* the
elements of these orbits may be found, conclusions drawn regarding the
absolute distance of the double stars from the Earth, and comparisons made
between their mass and that of the Sun.
[footnote] *Savary, in the 'Connaissance des Tems', 1830, p. 56 and 163.
Encke, 'Berl. Jahrb.', 1832, s. 253, etc. Arago, in the 'Annuaire' 1834, p.
260, 295. John Herschel, in the 'Memoirs of the Astronom. Soc.', vol. v.,
p. 171.
Whether, however, here and in our solar system, quantity of matter is the
only standard of the amount of attractive force, or whether 'specific'
forces of attraction proportionate to the mass may not at the same time come
into operation, as Bessel was the first to conjecture, are questions
p 148
whose practical solution must be left to future ages.
Pages:
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307