112422-01 Hubble, Edwin.
A General Study of Diffuse Galactic Nebulae.
(25,5 x 17 cm). 38 S. Mit 2 Tafeln und 2 Abbildungen. Original-Broschur. (Sonderdruck aus: Astrophysical Journal).
(Chicago, University of Chicago Press), 1927.
Erste Ausgabe. - "In one of his earliest papers, 'A General Study of Diffuse Galactic Nebulae,' he suggested a classification system based upon fundamental differences between galactic and nongalactic nebulae. He discovered many new planetary nebulae and variable stars, but the most important result of his early researches concerned the origin of the radiation from diffuse galactic nebulae. Hubble showed that they were made luminous by certain stars associated with them, the nebulosity consisting of clouds of atoms and dust not hot enough to be selfluminous. He discovered a relation between the luminosity of a diffuse galactic nebula and the magnitudes of the associated stars and showed that the gases were excited and made luminous by neighboring blue stars of high surface temperature" (DSB). - Hubble (1889-1953) war der Begründer der modernen extragalaktischen Astronomie und der erste, der die Rotverschiebung der Sterne beobachtete und damit den Nachweis für die Expansion des Universums lieferte. - Oberes Kapital etwas bestoßen, sonst sauber und gut erhalten. - DSB 6, 528