PDA

View Full Version : Aliens on This World Would See a Double Sunset



Fraser
2007-Feb-22, 11:27 PM
Imagine a world orbiting a star in a binary system. Two stars would shine in the day, and the rare nights would occur only when both stars had set below the horizon. ...

Read the full blog entry (http://www.universetoday.com/2007/02/22/aliens-on-this-world-would-see-a-double-sunset/?1336)

John Mendenhall
2007-Feb-23, 12:39 PM
So that's where Tatooine is!

ConceptJunkie
2007-Feb-23, 06:25 PM
How long is a system like this likely to be stable? I would imagine that there's a significant chance that the second star would cause the planet's orbit to be unstable enough that it would either crash into one of the stars or be flung free from the binary system after a few million years.

I can't imagine it's likely that such a planetary system would be stable long enough for life to evolve.

Nevertheless this is incredibly cool.

Gustavo 75
2007-Feb-24, 10:13 PM
The surface temperature of the imaginary planet would be enormous. Should it have a atmosphere it sould be like a sauna

Ilya
2007-Feb-25, 02:27 AM
The surface temperature of the imaginary planet would be enormous. Should it have a atmosphere it sould be like a sauna
Well, it's not imaginary... but you are right:

http://exoplanet.eu/star.php?st=Gamma+Cephei

http://www.astro.uiuc.edu/~kaler/sow/errai.html

Gamma Cephei A has luminosity 10.6 times Sun, and the planet orbits only twice as far as Earth from Sun. Which translates into ambient temprature of about 330 Kelvins (pretty much like a sauna, in fact). Which is not too bad, except atmospheres tend to raise the temperature -- something known as greenhouse effect.

In any case, the known planet is almost certainly a gas giant with no solid surface. Imaginary moons :) are a different story.