Brown Dwarf HZCO

Derpious

Mongoose
I don't know if maybe I've just missed it somewhere, but I'm trying to determine the HZCO for a Brown Dwarf in a close orbit to its primary star.

The table to determine Habitable Zone Center (AU) and HZCO doesn't account for Brown Dwarves, which is fair enough, so I tried to do it the math way.

The Brown Dwarf has a Luminosity of 0.00000052, which isn't a lot.

Maybe it's too little to be relevant?
 
In your scenario it is likely too little to be relevant, other than the disruption to the innermost regions of the system preventing orbits because a brown dwarf is present (it might actually have a weird effect of the brown dwarf coming closer to the planet, eclipsing the star and actually making things colder... but it would be weird and temporary math).

It would be relevant to a situation where a planet was in orbit around a distant companion brown dwarf, though, so the luminosity calculation does matter in that case. But brown and white dwarfs (and neutron stars for that matter) fall outside the tables and into the realm of... math.
 
Trappist-1 is so dim it's not much brighter than the brightest brown dwarf, so the big ones, yes. Another thing to consider is that a tidally locked world might be warm enough on the 'brown-dwarf-ward (?)' side. And tidal forces might also heat the world in an Io-like fashion if it has an eccentric orbit.
 
Wikipedia says:

Habitability for hypothetical planets orbiting brown dwarfs has been studied. Computer models suggesting conditions for these bodies to have habitable planets are very stringent, the habitable zone being narrow, close (T dwarf 0.005 AU) and decreasing with time, due to the cooling of the brown dwarf (they fuse for at most 10 million years). The orbits there would have to be of extremely low eccentricity (on the order of 10 to the minus 6) to avoid strong tidal forces that would trigger a runaway greenhouse effect on the planets, rendering them uninhabitable. There would also be no moons.[175]

So doable, but it would be a fairly transient thing. Great if your spacefaring civilization happens along at just the right time, but no good for long-term development of life.
 
I suppose it's a little irrelevant, I was mostly just wanting to fill out the box so to speak. While going through the system creation process, I like being able to develop any relevant information.

That being said, my general idea for the Brown Dwarf isn't really dependent on a habitable area, but I do have a second question. Would a Brown Dwarf be fuel-scoopable in the same way a Gas Giant is? As they're to a large part made up of not-burning hydrogen (if I've understood correctly), then surely they'd be just as good for refueling as Gas Giants? Albeit a bit hotter. A colder Brown Dwarf, closer to 300 - 800K should be feasible?

That was my idea anyway, a spaceport or artificial world type structure which orbits close to the Brown Dwarf siphoning hydrogen for fuel. Originally the idea was for the same thing but orbiting a Gas Giant, I thought a Brown Dwarf would be more exciting haha
 
You could, but it would be tricky. The gravity would be very high, and even if you assume a ship has lifters to nullify it, it likely means the kinetic energy of any falling object would be very great, so impacts could be catastrophic during approach departure. The latest article on the nearest pair of brown dwarfs talks about silica in the atmosphere - so imagine a hot howling wind of sand. It might be mostly hydrogen by volume, but there's a lot of nasties in there.

So, yes possible. Safe, unlikely, until you get down to Y class, some of which might be cool as room temperature, but still, very deep gravity wells.
 
With only a tiny bit of fudging, I managed to roll a Y2 class, so should be a lot safer.

How would I go about forming the SAH for an artificial world orbiting a BD?

Would it just be X60 (for example)?
 
With only a tiny bit of fudging, I managed to roll a Y2 class, so should be a lot safer.

How would I go about forming the SAH for an artificial world orbiting a BD?

Would it just be X60 (for example)?
Depends on the nature of the artificial world. The table on p.232 makes the assumption that an enclosed station, even if city-sized is Size 0, so 000 - since the atmosphere and water is likely to be on the inside only. Anything able to be build prior to TL18 fits in that Size 0 category.
 
Depends on the nature of the artificial world. The table on p.232 makes the assumption that an enclosed station, even if city-sized is Size 0, so 000 - since the atmosphere and water is likely to be on the inside only. Anything able to be build prior to TL18 fits in that Size 0 category.
Just out of curiosity, if you grav-plated the outside of the artificial world to 1g, could you then have atmosphere and hydrography? Or a prototype Gravity Well Generator from HG instead of or in addition to the surface-mounted grav-plates?

It is this kind of crap that players in My games come up with that makes Me need weird rules and clarifications...lol..

I kind of hope the answer will help the OP with other options for his artificial world building as well. :)

For Me it is all about understanding how the different systems relate to each other and effect each other. Then I can extrapolate on the fly if need be.
 
If you wanted to build something like that, I'd have some concerns of gas escaping if it was open-topped - once gas got above the effects of the grav plates, it would be subject to whatever the natural escape velocity of whatever mass the anchoring object had. The paraterraformed worlds in Solomani space are considered tent worlds, the prototype being Velscur in Alpha Crucis. Its SAH is listed as 100, So I think its safe to say that 'outside' needs to be covered for anything less than a major planetary massed object (minimum of Size 2).
 
If you wanted to build something like that, I'd have some concerns of gas escaping if it was open-topped - once gas got above the effects of the grav plates, it would be subject to whatever the natural escape velocity of whatever mass the anchoring object had. The paraterraformed worlds in Solomani space are considered tent worlds, the prototype being Velscur in Alpha Crucis. Its SAH is listed as 100, So I think its safe to say that 'outside' needs to be covered for anything less than a major planetary massed object (minimum of Size 2).
Doesn't the bigger of the two Gravity Well Generators have a radius of 1,200,000km? Isn't that the same gravity as a 12,000km world? If the gas doesn't escape from a planet, why would it escape from something with similar gravity? Solar radiation?
 
The gravity well generators are TL16 and 17 in the Apocrypha Exotic Technologies section. No idea how they work, but notice that they only say they disrupt jump drives as if they were within 100 planetary diameters of a body, never 10 or 1, so perhaps what they create is more of a 'shallow' effect, not as directly related to an inverse square point source drop of normal gravity (maybe they use anti-dark energy... to invent a thing that's the opposite of the thing nobody understands).

If it's just grav plates on an artificial world, then there's no indication (in fact because jumps happen, inferred contraindication) that the gravity effects of grav plates extend beyond the structure of the hull.
 
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