light -indices:

reference to star light magnitude, which astronomers assign a number denoting the brightness of a star or other celestial object; the higher the magnitude, the fainter the object, for example, a 1st-magnitude star is 100 times brighter than a 6th-magnitude star.

 

light-powers:

a somewhat convoluted, obtuse way to put into scientific dress the light which we see (optically) from stars; it a reference to the science of the measurement of light in terms of its perceived brightness to the human eye: photometry.  The radiant power at each wavelength is weighted by a luminosity function that models human brightness sensitivity.  Typically, this weighting function is the photopic sensitivity function.

 

Copernicus (Copernican world-idea):

aka the Copernican Revolution, a paradigm shift from the Ptolemaic model (in which Earth stood stationary at the centre of the universe) to the heliocentric model with the Sun at the centre of the Solar System.  Beginning with Copernicus’s “On the Revolutions of the Heavenly Spheres” (1543) the revolution continued until ending with Isaac Newton’s work over a century later. However the theory of Copernicus still maintained a finite universe with a sphere of fixed stars

 

corporeal-static:

relating to a physical, material body, at rest, without motion

 

Democritus (atomic theory):

see page 306 above

and see Chapter IV page 119, Chapter V, page 177 and above page 311

 

Bruno (expanded solar system): * see EndNote<A>

In 1584-85, while in England Bruno wrote a series of dialogues which included “On the Infinite Universe and Worlds” where he developed his cosmological theory.  While he reaffirmed the Copernican theory he also went beyond it by suggesting that the universe is infinite, made up of innumerable worlds substantially similar to those of the solar system. 

 

sum of all solar systems (35,000,000):

Since 1918 astronomy has advanced; astronomers have observed within a relatively small area of the Milky Way 500 solar systems complete with planets.  Based on these observations they estimate there are tens of BILLIONS, and perhaps as many as a hundred billion, solar systems in the galaxy!

 

stellar system:

aka star system, a designation which includes galaxies & star cluster, and in this particular “stellar system” Spengler is referring to the Milky Way galaxy.

 

ellipsoid: * see EndNote<B>

surface that may be obtained from a sphere by deforming it by means of directional scaling or an affine transformation

 

solar systems traverse this space: * see EndNote<C>

In 1869 astronomers first identified “moving groups”: the remnants of a stellar association drifting through the Milky Way as a coherent assemblage of stars, moving in the same direction, showing a common point of convergence.  Proctor was the first to observe this; he noted several hundred stars in the Hyades star cluster in Taurus, forming a gravitationally-bound swarm, 151 light years from Earth, all sharing a similar motion through space.  Some 39 years later (1908) Boss corroborated his observations.  He reported another co-moving group of stars he called the Taurus Stream (later known as the Hyades Stream).  In 1909 Hertzsprung identified the Ursa Major moving cluster & showed that several stars in the near solar neighbourhood (such as the star Capella) were moving in space like the Hyades.  Their point of origin was the same.  

 

apex in the constellation of Hercules: * see EndNote<D>

the solar apex is the direction the Sun travels with respect to the local standard of rest.  This is not the Sun's apparent motion through the zodiac (an illusion caused by the orbit of the Earth).  In 1783 William Herschel demonstrated the nature and extent of the solar motion which he determined (the solar apex) was Lambda Herculis a star in the constellation of Hercules, SW of Vega.  The Sun moves towards the apex (a relatively local point) at about 1⁄13 our spiral arm's orbital speed.  

 

Capella, Vega, Altair and Betelgeuse: * see EndNote<E>

4 notable stars, 3 very close to the Sun; the forth, Betelgeuse, is in Orion, home of the Solar System.  Of these only 1 is associated with a moving cluster- Capella (the Ursa Major moving cluster).  Betelgeuse is believed to be a lone star without any cluster associations.