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In fact when Cecilia Payne proposed that the Sun and other stars were composed of Hydrogen and Helium in her Doctoral thesis in 1925 the conclusion was rejected
by robotbikes 6y ago
In fact when Cecilia Payne proposed that the Sun and other stars were composed of Hydrogen and Helium in her Doctoral thesis in 1925 the conclusion was rejected by her advisor because of the conventional wisdom of the time that the earth and the sun were composed of the same elements. https://en.m.wikipedia.org/wiki/Cecilia_Payne-Gaposchkin https://en.m.wikipedia.org/wiki/Cecilia_Payne-Gaposchkin
- asveikau 6y agoI thought helium was named for the sun (Helios), by spectral analysis of sunlight. In hindsight it's weird that they can know that in the 19th century (per Wikipedia of Helium) and the next conclusion has to wait until 1925, with controversy.
- pishpash 6y agoThey probably thought it was an inert atmosphere found on the Sun but having nothing to do with the operation of the Sun. Without nuclear physics, it wouldn't be an unreasonable conclusion.
- pfdietz 6y agoAnd the helium that can be "seen" on the Sun is not due to fusion IN the Sun, but rather is from the gas cloud from which the Sun formed. The solar core and the surface are not connected by convection.
- acqq 6y ago> In hindsight it's weird Not, if you know that there was simply not even a concept of nuclear fusion in 19th century, and that the year of discovery of electron is 1897, and of the existence of atomic nucleus 1909. Tangentially, but also interesting and illuminating how non-trivial all that was at that times, neutron was discovered as late as 1932 -- the same year that Hitler became chancellor of Germany. It is that recent, and it was that hard.