JF Ptak Science Books Quick Post
Deep into a stellar, pioneering, and very productive 350-paper career (Pierre Jules Cesar Jules Janssen, 1824-1907) wrote this interesting paper that appeared in Appleton's Popular Science Monthly (volume 50) in 1897 (translated from his address to the French Academy of Sciences on 24 October 1896), speculating on the possibility of teeming life elsewhere and on the unity of the laws of science and nature. He was a great traveler in the name of astronomy, an independent researcher with a house in Montmarte and a maker of his own telescopes and spectroscopes (that in the first decade of the science), who via a mistaken identification of finding oxygen in the spectrum of Mars1 (1867-1869, in the middle year of that discovering helium), came to a realization that life existed on Mars. And from there Janssen went on to create the possibility of worlds throughout the universe, all brought about by the creation of the science of astrophysics in which he made such important contributions. There's a lot in these few short pages, including this interesting speculation:
- "I say further that what we know of the unity of the chemical composition of the matter of the sun, the stars,
and the nebulae permits us to make new inductions respecting the part performed by the bodies which are
on the earth the most important factors of the phenomena of life. It is thus infinitely probable that hydrogen,
oxygen, nitrogen, carbon, and especially water, which on the earth are the indispensable constituents of
vegetable and animal life, fill a like office not only in the planets of our system, but throughout the universe."
Janssen is one of many who speculated on life in the universe, even among spectroscopists of Janssen's time (including William Huggins, Angelo Seechi, Heinrich Schellen), part of a continuum of thinkers reaching back to Bruno (1584), Kepler (Somnium, 1634), Wilkins (Discovery of a World in the Moone..., Borel (1657), Fontenelle (the great Pluralitie des mondes, 1686), Huygens (1698), Derham (1714)...the list begins to get pretty crowded in the 18th century.
- [Images sources all via Internet Archive, here: https://archive.org/stream/popularsciencemo50newy#page/812/mode/2up]
For interesting reading, see: Michael Crowe, Extraterrestrial Life Debate, 1750-1900... and Douglas A. Vakoch, Matthew F. Dowd (eds) The Drake Equation: Estimating the Prevalence of Extraterrestrial Life ...
1, W.W. Campbell showed that Janssen's results of finding oxygen in the spectrum of Mars (and Saturn) was spurious, and that the oxygen identified was of terrestrial origin.