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Engineering a Solar System

20 points by sanj 3y ago

sanj 3y ago
And visuals! https://lucas.bourneuf.net/blog/uess.html https://lucas.bourneuf.net/blog/uess.html
pmontra 3y ago
Great achievement! It made me remember the Kiint home system in the Night's Dawn trilogy [1] [1] https://nightsdawn.fandom.com/wiki/Kiint_home_system https://nightsdawn.fandom.com/wiki/Kiint_home_system
_boffin_ 3y ago
Wouldn't each object on each ring pull on one another and cause stability issues of that structure due to their relative closeness?
friend_and_foe 3y ago
Of course, habitability largely relies on radiation from the star hitting the surface. A system like this would mean that the second ring from the star would experience multiple eclipses a day, the third even more and so on. These affect habitability considerably. By the time you're on the outermost ring you'll be cutting the amount of radiation reaching the surface down, I suspect, well below habitability. You can resolve this to some degree with a complex design for tilted orbits, but they'd intersect somewhere, so you're still reducing radiation often enough that you narrow your zone of habitability. The habitable zone is the zone in which, unobstructed, the area of the disc of a planet receives enough radiation from the star that it is warm. It's all about the surface area of the star and it's luminosity, and the area of the disc of the planet. Anything obscuring direct line of sight between the star and the planet effectively reduces the luminosity of the star from the perspective of the planet.
- bediger4000 3y ago
  Couldn't the plane of each concentric orbit be a little different, minimizing the problem?
  - friend_and_foe 3y ago
    Sure, you can skew the orbits so that they're not on the same plane, but you'll get partial transits and full transits the closer you get to the intersection points, and I don't know what this would do to the gravitational mechanics of such a system.
- jccooper 3y ago
  Seems that the Earth's shadow is 1.4 million km, and the Hill radius around 1.5 million. That ratio won't be the same for different size planets, as they scale differently with mass, but I doubt you'll get eclipses in any plausible configuration.
  - friend_and_foe 3y ago
    If you can see Venus transits you'll be able to see these. Multiple daily, dozens to hundreds the farther out you are from the innermost orbit. The amount of energy that hits the surface in a year is what determines habitability. The effect of these eclipses is cumulative. It shrinks the habitable zone the more rings you out into such a configuration.

20 points by sanj 3y ago

sanj 3y ago

And visuals! https://lucas.bourneuf.net/blog/uess.html https://lucas.bourneuf.net/blog/uess.html

Great achievement! It made me remember the Kiint home system in the Night's Dawn trilogy [1] [1] https://nightsdawn.fandom.com/wiki/Kiint_home_system https://nightsdawn.fandom.com/wiki/Kiint_home_system

_boffin_ 3y ago

Wouldn't each object on each ring pull on one another and cause stability issues of that structure due to their relative closeness?

friend_and_foe 3y ago

Of course, habitability largely relies on radiation from the star hitting the surface. A system like this would mean that the second ring from the star would experience multiple eclipses a day, the third even more and so on. These affect habitability considerably. By the time you're on the outermost ring you'll be cutting the amount of radiation reaching the surface down, I suspect, well below habitability. You can resolve this to some degree with a complex design for tilted orbits, but they'd intersect somewhere, so you're still reducing radiation often enough that you narrow your zone of habitability. The habitable zone is the zone in which, unobstructed, the area of the disc of a planet receives enough radiation from the star that it is warm. It's all about the surface area of the star and it's luminosity, and the area of the disc of the planet. Anything obscuring direct line of sight between the star and the planet effectively reduces the luminosity of the star from the perspective of the planet.

bediger4000 3y ago
Couldn't the plane of each concentric orbit be a little different, minimizing the problem?
- friend_and_foe 3y ago
  Sure, you can skew the orbits so that they're not on the same plane, but you'll get partial transits and full transits the closer you get to the intersection points, and I don't know what this would do to the gravitational mechanics of such a system.
jccooper 3y ago
Seems that the Earth's shadow is 1.4 million km, and the Hill radius around 1.5 million. That ratio won't be the same for different size planets, as they scale differently with mass, but I doubt you'll get eclipses in any plausible configuration.
- friend_and_foe 3y ago
  If you can see Venus transits you'll be able to see these. Multiple daily, dozens to hundreds the farther out you are from the innermost orbit. The amount of energy that hits the surface in a year is what determines habitability. The effect of these eclipses is cumulative. It shrinks the habitable zone the more rings you out into such a configuration.