I have talked before about this system in one of my other questions. I have figured out some more info about the planets/stars. I want to know where is the habitable zone and any other info you can tell me. I have done some math and I will show an illustration of the system. You can assume some things. Depiction of two concentric circles signifying the orbits of celestial bodies. The outer circle has one marked in green, while the inner circle shows two on opposite sides of each other. One of them is yellow, the other is red.

Red star:

  • Mass(kg): 4.62006E+21
  • Radius(m): 139140000

Red dwarf

Yellow star:

  • Mass(kg): 3.63803E+18
  • Radius(m): 785035685

Star like are sun

Distance between stars: 1.25 Au

Green planet:

  • Has life
  • Mass(kg): 9.40135E+17
  • Radius(m): 6378100
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    $\begingroup$ You forgot to tell the distance between the stars $\endgroup$
    – L.Dutch
    Dec 10 '19 at 18:52
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    $\begingroup$ The red star is only slightly more massive than the Uranian satellite Titania. They are not stars: they are cold dead worlds and there is no habitable zone. $\endgroup$
    – user66717
    Dec 10 '19 at 20:56
  • $\begingroup$ Yes a bit on the light side for stars. Our sun has a mass of 2x10^30 kg $\endgroup$
    – Slarty
    Dec 10 '19 at 23:53
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    $\begingroup$ To give some examples slightly closer to home than Slarty's and antispinwards', Earth has a mass of ~6e24 kg and the moon 7e22. Heck, most of your stellar bodies are smaller than the largest asteroids in the Belt. 48 Doris weighs in at 1.2e19 kg and is ~220 km across $\endgroup$ Dec 11 '19 at 0:01

Your stars' masses are far too small. For comparison, the mass of Earth is $\sim6\times10^{24}\text{ kg}$, and the mass of the Sun is $\sim2\times10^{30}\text{ kg}$. I chose some representative parameters for a "yellow star" and a "red star":

  1. Star 1: $M\simeq0.97M_{\odot}$, $L\simeq0.78L_{\odot}$, spectral type G6V
  2. Star 2: $M\simeq0.22M_{\odot}$, $L\simeq0.0063L_{\odot}$, spectral type M4V

Then I used some code I put together a while ago to determine the habitable zone of the system, assuming a planet with albedo $a\approx0.3$:

Plot of habitable zone of binary star system

The habitable zone is in black. We see that there is no habitable zone for a circumbinary orbit, like the one you describe, but both stars do host their own habitable zones. The major problem is that the red dwarf is so dim that its habitable zone is tiny, and any orbit that remained within it would be naturally gravitationally bound to just the smaller star.


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