What kind of star will work for my system?
After what feels like forever and after asking several questions (like this, this and this), I believe I may have decided upon a suitable orbital system for my world:
$M_{S}=2.272\;571\;144\;5 \times 10^{30} = 1.142\;857$ $\color{blue}{\underline{M_☉}}$
$M_{P}= 1.898\;2 \times 10^{27} = 1 $ $\color{blue}{\underline{M_J}}$
$M_{M}= 2.272\;686\;259\;599\;33 \times 10^{25} = 3.806\;844 $ $\color{blue}{\underline{M_⊕}}$
$D_P = 324,936,410.689\;212 $
$D_M = 14,596,597.842\;622\;8 $
$AD_S \approx 1929\; \mathrm{arcseconds} $
$AD_{P\,min} = 2374.8 \; \mathrm{arcseconds} $
$AD_{P\,max} = 2879.4 \; \mathrm{arcseconds} $
where $M_S$ is the mass of the sun in kilograms; $M_P$ is the mass of the planet my world orbits in kilograms; $M_M$ is the mass of my world (it's an Earth-like moon) in kilograms; $D_P$ is the average distance (semi-major axis) from the planet to the sun in kilometers; $D_M$ is the average distance from the moon to the planet in kilometers; $AD_S$ in the angular diameter of the sun (as viewed from the planet) in arcseconds; $AD_{P\,min}$ is the minimum angular diameter of the planet (as viewed from the moon) in arcseconds; $AD_{P\,max}$ is the maximum angular diameter of the planet (as viewed from the moon) in arcseconds;
One year in my world is defined at the amount of time it takes the Earth-like moon to orbit around the planet, which should be equal to about 360.3126455 real-life Earth days. The amount of time it takes for the planet to orbit around the sun is about 1093.734343 real-life Earth days.
I have calculated the radius of the planet's Hill Sphere in this system as 21217756.17 km, which allows my Earth-like moon to orbit at the desired orbital period and distance.
The problem
My main issue here is the sun. The distance from the planet to the sun is a little further than Mars is to our own sun. If I am not mistaken, under normal circumstances, this would place the planet outside of the habitable zone where life can form.
What kind of sun can have a mass of 1.142 solar masses and have a habitable zone 324,936,410 km away?
For bonus points, I'd like to have my sun have a similar angular diameter when viewed from the planet as our real-life sun, which is approximately 1929 arcseconds.
NOTE: I have re-read this question very carefully to ensure I only use the term 'planet' to refer to the body in direct orbit of the sun. Similarly, 'Earth-like moon' or just 'moon' is used to refer to the main setting of my world, which is actually a moon orbiting a larger Jupiter-like planet.
UPDATE: It might not be possible with these numbers
I'm looking for a habitable zone that is large enough to accommodate the distance between the planet and the moon. So the Earth-like moon should never leave the habitable zone.
How far from the sun can I place the planet, where there is a type of star that might be feasible for the majority of the requirements above?
This post was sourced from https://worldbuilding.stackexchange.com/q/160845. It is licensed under CC BY-SA 4.0.
1 answer
For a star of that mass, you are looking at a G0V to F9V main sequence star. It's luminosity, depending on age, is probably around 1.2 sol, from which you can calculate the bounds of the habitable zone.
The inner edge of the zone is around 1.04 AU.
The comfortable outer limit is around 1.5 AU.
The maximum outer limit is around 1.86 AU.
Your planet's moon, at a distance of 2.17 AU, is uninhabitable for Earth-like conditions.
However, as stars age, they become more luminous. It is entirely possible that at some point before the star reaches the end of its main sequence lifespan, luminosity will be high enough for the maximum outer edge of the habitable zone to reach 2.17 AU.
Estimates of circumstellar habitable zone limits from Kasting et al. 1993, Kopparapu et al. 2013
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