Astrophysik contra Astronomie

[Astrophysics contra astronomy] means the displacement of astrometry and stellar astronomy as the main and solely conceded branches of astronomy by the new astrophysics. This displacement started with the introduction of spectroscopic and photometric methods of observation in astronomy founded by J. C. F. Zoellner and W. Huggins in the late 1850s. It was Zoellner, too, who gave the methodical and intrumental foundations of the new branch called consciously [Astrophysik] by him, because it gives insight into the [physical constitution] of the celestial bodies ‐ whereas the traditional astronomy (or: astrophysics according to the older meaning) had been studying only the motions of the stars and other celestial bodies and refusing searches for the [physical constitution] (named [physical astronomy], [physische Astronomie]) as speculations not being proper to a member of the guild of astronomers. Until the middle of the nineteenth century this guild was led by F. W. Bessel who (in the first half of this century) together with other members of his school brought forth the fundamental results of celestial mechanics and observational astronomy based on Newtonian physics (mechanics) extended to objects outside the solar system. Therefore already in the end of the 18th century, J. Chr. Lichtenberg had called astronomy the [paradigmatic] branch of all natural sciences; and therefore, Zoellner had to confirm the extension of the possibilities of experience (transmitted by the light of the celestial bodies) through the same methodical certainty. The new methods, however, made their way only tardily (especially in Germany), but later on, indeed, they pushed back the traditional branches of astronomy into the background ‐ resuscitated only by new astrophysical formulations of old questions previously refused by traditional astronomy.