What did we know about stars in 1950?

[Octavianus]

I was reading an old Asimov novel called Pebble in the Sky, and it somewhat irked me that Sirius and Aldebaran were described as major stat systems of the Galactic Empire.
Sirius is too young to have had time to develop planets with higher life (if evolution on Earth is anything to go by), and Aldebaran is an Orange Giant which would have eaten up planets in the habitable zone.
But was this known in 1950? I think it was, but I'm no expert on the matter, so I may be wrong.

 

[rootone]

We did know most of the different kinds of stars that we know today..
However we knew almost nothing of planetary systems other than the solar system
It was a reasonable thought at the time that our solar system could be a rare exception .

 

[Bandersnatch]

According to Thomas Arny's 'The star makers: A history of the theories of stellar structure and evolution' the 1930-50s was a period where some major work on stellar evolution was done by Gamow, Opik, Chandrasekhar, Schwarzschild, Hayashi, and the like. That is to say, the foundations of the modern theory of stellar structure were only being developed, with a lot of false leads and dead ends being explored, only to be shot down a few years later.
For example, there were models proposed in which giants were young stars, or where stars evolved up the H-R diagram.

Considering that the story was written in 1947, Asimov can't be faulted for not getting this right.

 

[PAllen]

Just a nit - Karl Scwarzschild died in 1916, right deriving the first exact solution in GR.

 

[George Jones]

Just a nit - Karl Scwarzschild died in 1916, right deriving the first exact solution in GR.

I think that @Bandersnatch meant Karl's son, Martin, who was a well-known astrophysicist,

https://en.wikipedia.org/wiki/Martin_Schwarzschild

 

[Bandersnatch]

Of course, that should be specifically Martin, as @George Jones correctly surmised, since that's the man who's done some breakthrough work in the 50s.
But to be perfectly honest, I had them both mixed in my head at the time of writing, like an absolute dunce.
In my hastily constructed defence, both did contribute - the father through his earlier work on radiative transfer, which was then followed by Eddington's.

 

[CygnusX-1]

From Ken Croswell's book The Alchemy of the Heavens:

"My mother maintained," said Martin Schwarzschild, "that from the moment I could say the word sterne---that is, in German, `stars'---I wanted to become an astronomer." Karl Schwarzschild, who was Jewish, had died in World War I just before Schwarzschild turned four. But otherwise, said Schwarzschild, "I had a very, very happy childhood, indeed a very happy growing period---until the Nazis came."

---The Alchemy of the Heavens by Ken Croswell, page 96.

 

[Simon Peach]

In the late '50s when I became interested astronomy it was said that there was no way that we could ever see a star. The only way we will ever see them is as a point of light, "the laws of optics would never let us see the star as anything other than as a point" !

 

[sunrah]

Martin Schwarzschild's book "Structure and Evolution of the Stars" was published in 1958. It's a good read and covers the stellar theory we know today, but it's obvious that there was a serious lack of data at that time. For example, on page 16 he says

Regarding the masses of stars not belonging to the main sequence, the available accurate data are as yet depressingly few. In fact, they are all summarised in Table 2.3.

Well, I can tell you Table 2.3 lists the masses of a grand total of five stars (one giant, two subgiants and three white dwarfs). Stellar masses were only worked out directly for binary systems (I don't think this has changed as far as I know), for spectroscopic and visual binaries he cites a total of 22 main sequence pairs as being accurately measured. Not a lot really.

I think it's fair to assume that writers like Isaac Asimov had a lot more leeway back then when it came to sci-fi.