Youtube Edgar here and welcome to Artifexian
Here you will learn everything you ever wanted to know about world-building and then some...
The last video was all about giving your hot jupiters hot neptunes and hot saturns stable
orbits.
In this video let's discuss Classical gas giants Super jupiters Gas dwarf and eccentric
jupiters same method plus a few modifications
1. Semi major axis
So the frost line is a particular distance from a star where its cold enough for the
building blocks of gas giants volatile compounds to exist in solid form.
Expect to find classical gas giants like jupiter here
1 to 1.2 AU from the frost line and beyond
Remember the location of the frost line is given by 4.85 * sqrt(L) where L is the luminosity
of your star relative to our sun
Super jupiters more massive version of jupiter can be found in this zone i.e Between 0.04
AU and the frost line plus 1 -1.2 AU
Although the frost line will likely be where your systems most massive gas giant will form
Migration may occur and a super jupiter formed there could wander inwards
Wasp 18 b is an example of a super jupiter that likely formed at the frost line and then
migrated inwards
It’s 10 times the mass of jupiter and orbits at 0.02 AU
Place gas dwarfs gaseous planets up 10 earth masses here
Between 1 - 1.2 AU from the frost line and the outer limits of your planetary system
Which by the way is given by 40 x M where M is the mass of your star in solar masses
For extra added realism try and stick to a very distant orbit for your gas dwarfs
Finally for all intensive purposes eccentric jupiters are totally renegades and can orbit
pretty much anywhere in a system
Speaking of eccentric...
2. Orbital Eccentricity
Classical Jupiters Gas dwarf and Super jupiters will tend to be on very circular orbits so
our eccentricity range of 0.00x – 0.0x from the previous video still holds
Eccentric jupiters however will have orbital eccentricities or 0.1 or greater
Remember if you want your system to have a habitable earth-like planet AND an eccentric
jupiter keep the eccentricity of your eccentric jupiter between 0.1 and 0.2
This reduce the gravitationally devastating effect eccentric jupiter can have on their
systems
This is a friendly eccentric jupiter so to speak and this...a not so friendly one
Check the out difference
3. Semi-minor axis Periapsis Apoapsis and Orbital Period
No special consideration needs to be take here when calculating the semi-minor axis
periapsis apoapsis and orbital period for your classical gas giants super jupiters gas
dwarfs and eccentric jupiters
This is because all of these orbital elements rely on the semi-major axis and eccentricity
which we've already discussed
But just to recap the eqautions from the last video were
The semi-minor axis is given by b = a*sqrt(1-e^2)
Periapsis is given by a(1 – e)
Apoapsis is given by a(1 + e)
and orbital period is given by P = sqrt(a^3)/M
In all cases a is the semi-major axis in AU e is eccentricy and M is the mass of your
planet's star in solar masses
4. Inclination
For classical gas giants super jupiters gas dwarfs and eccentric jupiters ensure that
they orbit in a prograde fashion i.e in the same direction as their parent star
For all four types of giant planet choose an orbital inclination between 0 and 90 degrees
A warning though don't go wild save the really highly inclined orbits for your kuiper belt
objects
I mean look at the gas giants in our system their orbital inclinations lie between 0.77
and 2.48 degrees
5. Longitude of the ascending node and argument of periapsis
Longitude of the ascending node values range from 0 to 360 degrees and determine the orientaion
of your orbit in 3d space about the y axis
Argument of periapsis values again range between 0 and 360 degrees and determine the orbits
orientation about the z axis
Feel free to choose values at will for both the longitude of the ascending node and argument
of periapsis
Got it cool
To give you a sense of scale heres a system featuring all the types of gas giants discussed
in this video and the previous video
Namely a hot jupiters a super jupiter a classical gas giant an eccentric jupiter and a gas dwarf
Stats on this system and its planets in the doobly doo if you're interested
Happy building everyone.
Good morning inter web
Welcome to the new end card
I really hope you enjoyed this video on how to put other gas giants into orbit
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Thank you all so much from watching
Edgar out!