Friday 5 December 2014

Blue Star

According to my information (see here), F-type stars are yellow white and are separated by white A's from blue B's and O's. However, in Poul Anderson's "Hunters of the Sky Cave," the F-type Cerulia:

"...glistened keen and blue ahead." (Sir Dominic Flandry, p. 204)

Maybe Cerulia is blue-shifted because Flandry's spaceship, the Hooligan, is moving towards it? No, after the Hooligan has entered the Cerulian System and is falling towards the planet Vixen, Cerulia is still being described as "...the harsh blue sun..." (p. 212).

Poul Anderson always describes extrasolar planets and their primaries in meticulous detail but I have never until now paid any attention to spectral types or to whether what is said about them seems to be accurate.

Anderson usually makes clear how a landscape on an extraterrestrial planet differs from any of its Terrestrial counterparts - different colors of vegetation for a start. The Shaw on Vixen is merely described as "...tall trees..." (p. 216). However, it does have at least one unEarthly feature:

"...here and there on the high trunks glowed yellow phosphorescent fungi, enough to see by." (p. 217)

While reading Anderson's speculative fiction, we always remember that the environments of other planets do not simply reproduce what is to be found on Earth.

1 comment:

Jim Baerg said...

Star colors are complicated by the human visual system adjusting to the light spectrum to make a good estimate of the color of the object regardless of the color of the illumination.
Eg: an incandescent light bulb has about the same temperature as a M type star & so if we can compare to noon sunlight we can see that it is somewhat redder than sunlight, but it looks perfectly white when illuminating a room at night.

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