Nightfall: Can Kalgash Exist? 86
First time accepted submitter jIyajbe (662197) writes Two researchers from the Indian Institute of Astrophysics investigate the imaginary world of Kalgash, a planetary system based on the novel 'Nightfall' (Asimov & Silverberg, 1991). From the arXiv paper: "The system consists of a planet, a moon and an astonishing six suns. The six stars cause the wider universe to be invisible to the inhabitants of the planet. The author explores the consequences of an eclipse and the resulting darkness which the Kalgash people experience for the first time. Our task is to verify if this system is feasible, from the duration of the eclipse, the 'invisibility' of the universe to the complex orbital dynamics." Their conclusion? "We have explored several aspects of Asimov's novel. We have found that the suns, especially Dovim are bright enough to blot out the stars. Kalgash 2 can eclipse Dovim for a period of 9 hours. We also tested one possible star configuration and after running some simulations, we found that the system is possible for short periods of time."
Re:Beh (Score:5, Insightful)
The words of a true fanatic.
Nevermind the work, the science and the data. It's written in a format I dislike.
*slowclap* well done, sir.
Stability (Score:5, Insightful)
Asimov's story only assumes that the suns' and planets' orbits are in that configuration for a few tens or maybe hundreds of thousands of years, not that they are stable for what astronomers would call the long term.
Re:An excellent book... (Score:5, Insightful)
Anything by Asimov is recommendable.
Re:fundementally impossible (Score:4, Insightful)
The problem is not the six suns but the constraints on the planet and moon:
* that the planet's orbit be stable over thousands of years. Millions or billions, if you want life to evolve.
* that the moon stay invisible at all times -- never be illuminated enough by any sun to be visible.
* that the moon be wide enough in angular size to eclipse one sun for over a day!
If you read this paper, you see they settled on a moon the same mass as Kalgash but with the density of Saturn! How could such a system possibly arise?