Worlds orbiting gas giants and jump distances

[dayriff]

So I find when making new worlds, I am often tempted to put them in orbit around gas giants. This is especially true for Size 0 to 2 worlds, as it makes sense in my mind that you would want to be close to a source of hydrocarbons. However, I also have a fondness for 'forest moon of Endor' type habitable worlds with a gas giant hanging on the horizon. It just makes for a great visual image. (I know that Jupiter style gas giants have intense radiation belts, but I don't believe that Neptune or Uranus style gas giants have the same problem.)

This does an interesting thing to jump distances, though. Rather than the 100-diameter limit being something that even a Thrust-1 ship can breeze through quickly, it can take a day or more (depending on the size of the gas giant and the thrust of your ship) of traveling through physical space to get in and out of jump range.

On reflection, I'm not sure this is a bad thing. I like to encourage more in-system travel, and it gives more of a range for pirate attacks and general in-system events. People settling a world aren't necessarily going to have the convenience of interstellar commerce at the top of their priority list, so I think it works well there.

Is anyone else really fond of worlds circling gas giants?

 

[dayriff]

Within the 3I setting these worlds make little sense. Cheap access to space and FTL travel means that marginal/dangerous worlds will be bypassed or end up as minor outposts. Same for terraforming - choose another world instead, it's cheaper.

Why do you characterize these worlds as marginal/dangerous?

There doesn't seem to me to be any reason that they should be more or less marginal/dangerous than a world that orbits a star on its own rather than being part of a gas giant system.

I guess it depends on how significant you think requiring some extra transit time for insterstellar ships is.

 

[rust]

Is anyone else really fond of worlds circling gas giants?

Not really, because a small world orbiting close to a gas giant would be
very likely to have serious problems with tidal stress as well as with ra-
diation, depending on the system's structure the gas giant will block out
the sun for long periods of time, and gas giants also have a tendency to
attract lots of comets and various other debris into their orbits.

All in all, I would rather be in Philadelphia.

 

[DFW]

[All in all, I would rather be in Philadelphia.

I don't know about that. Philly attracts stuff worse than comets and debris.

 

[rust]

I don't know about that. Philly attracts stuff worse than comets and debris.

Yep, but the flight ticket from Philadelphia to Germany is much more af-
fordable than the one from the gas giant to Germany. 8)

 

[DFW]

+ Waaay out in the system so the world is either very cold (Think Europa) or orbits a HUGE (Super)Jupiter GG that radiates additional energy

That part isn't actually true. GGs can be in any orbit.

 

[DFW]

According to the generation system or to reality? The Traveller systems have some problems when it comes to system generation. Sometimes a healthy does of "human intervention"

Reality. I use fantasy when playing FRPGs.

 

[starpilot]

Not really, because a small world orbiting close to a gas giant would be very likely to have serious problems with tidal stress as well as with radiation, depending on the system's structure the gas giant will block out the sun for long periods of time, and gas giants also have a tendency to
attract lots of comets and various other debris into their orbits.

"Serious problems" = good roleplaying environment.

 

[Mithras]

Is Schimanski still going? I loved that series all those years ago!

Within the 3I setting these worlds make little sense. Cheap access to space and FTL travel means that marginal/dangerous worlds will be bypassed or end up as minor outposts. Same for terraforming - choose another world instead, it's cheaper.

Why do you characterize these worlds as marginal/dangerous?

There doesn't seem to me to be any reason that they should be more or less marginal/dangerous than a world that orbits a star on its own rather than being part of a gas giant system.

I guess it depends on how significant you think requiring some extra transit time for insterstellar ships is.

+ More tidal stress (gas giant and the sun)
+ More radiation even with the smaller GG (that have rad belts!)
+ More meteroid strikes (All GG are subjected to them IRL, same for the moons)
+ Waaay out in the system so the world is either very cold (Think Europa) or orbits a HUGE (Super)Jupiter GG that radiates additional energy
+ Small size typically means low athmosphere/little water retention

and so on. Marginal worlds for a civilization that has an earth like Garden world just a Jump or two away. Why take a world with problems when you can have one without.

Settling this GG moons is like living in Duisburg(1) when you could just as well live in Moers. Or choosing Köln-Chorweiler(2) over Hürth. No sane person would do so.

(1) A city SO wrecked that they filmed the "slum scenes" for the long-running "Schimanski" Tatorts (that play in Duisburg) in another city - the original was too run down and dangerous.
(2) Comment from a turkish-borne collegue: "Don't go there, it's where all the Turks live"

 

[dayriff]

+ More tidal stress (gas giant and the sun)
+ More radiation even with the smaller GG (that have rad belts!)
+ More meteroid strikes (All GG are subjected to them IRL, same for the moons)
+ Waaay out in the system so the world is either very cold (Think Europa) or orbits a HUGE (Super)Jupiter GG that radiates additional energy
+ Small size typically means low athmosphere/little water retention

It's not clear to me that we know enough about planetary science to be able to predict how extensive those problems would necessarily be.

Will more tidal stress be a problem for day-to-day life? Maybe, maybe not. It may just mean that you really, really don't want to build on any fault lines, but elsewhere on the world is perfectly fine.

More radiation? Don't build around GG that have intense rad belts.

More meteroid strikes? Not as much of a problem on worlds with an actual atmosphere to burn up the meteors before they hit. If you don't have an atmosphere, you've likely got the tech in place to make it a mere annoyance.

Way out in the system? Addressed; we're finding gas giants at every orbital distance.

Small size? Well, for 2 and lower it's basically just a big space station and as I said, for a space station there are definite advantages to being next door to a ready supply of hydrogen to power all those fusion plants. And we don't have any upper limit for how big worlds orbiting gas gaints can be. No reason they can't be as big as Earth.

I should add that from a defensive perspective, being able to see ships from hours away is a darn good thing. If I had a Navy base as a space station, I would definitely want to hug a gas giant so that nobody can jump out of jumpspace and spray me with missiles from a half light -second away.

 

[DFW]

I should add that from a defensive perspective, being able to see ships from hours away is a darn good thing. If I had a Navy base as a space station, I would definitely want to hug a gas giant so that nobody can jump out of jumpspace and spray me with missiles from a half light -second away.

THAT'S a very good point dayriff.

 

[DFW]

That's a reason for an outpost/defence base. Not for a colony

If it's in the habitable zone with an "M" class planet in orbit, it's a GOOD reason.

 

[Cyphr]

All in all, I would rather be in Philadelphia.

No you don't it is hot and humid right now. :lol: :wink:

 

[DFW]

That's a reason for an outpost/defence base. Not for a colony

A large "M" class planet isn't a reason for a colony? Really? Where's the logic in that?

 

[dayriff]

Jupiter and Saturn as well as their moons and rings offer good examples for a start

I see no reason to assume that two examples are necessarily representative of how every gas giant must be. We have four GG in our solar system; two of them don't seem that great; and two might be good if they were in the habitable zone and had the appropraite type of world circling them. If one in twenty GG had conditions where a single world was prime colony real estate, that would be plenty on an interstellar scale.

Take a look at Io and Europe as well as at least one of Saturns moons. And the rings of the gas giants too. And then think about a civilization that can choose. Why would it settle on such an ugly world?

Those are examples of how it can be, not how it must be.

All gas giants in our system have. And unless you really get one in the "life zone" orbit of the sun you need a "hot" planet like Jupiter to get some energy to your world to support some life.

Again, I think I can credibly posit a GG that doesn't have a radiation belt that makes life impossible on a moon with an atmosphere and magnetic field comparable to that of earth to block the radiation.

We just don't know enough about extrasolar planets for anyone to tell me I'm absolutely wrong.

Even with an athmosphere they are a problem. And with rings etc. as a steady source of debris you get a lot of alerts and problems, even more without (or with a thin) athmosphere. It might be doabel but again: WHY? The next system has a nice garden world waiting to be settled...

Because the garden world is around a gas giant?

You seem awfully resistant to this idea for some reason.

 

[DFW]

A habitable planet (Class M is from that third rate TV show with that canadian guy, isn't it) in a problematic position. Not really a reason for settlement in the OTU.

Why?

 

[DFW]

Because I can settle on a better world just as easily. The 3I has little reason to settle second best. The classic reasons (Population pressure mainly) do not apply. So unless the world offers something special why settle it and not the first rate world next system-

The question is; what data are you using to label it as "2nd best"? I understand that is your consideration, you just haven't explained why.

 

[DFW]

So if one world has problems/potential problems (Radiation, long STL travel, etc) the other has not then, assuming both are otherwise "identical" (No special minerals etc) world 2 is better.

Yes, that explains all the sub-standard non-garden worlds colonized in the Spinward Marches. Apparently, perfect worlds are in shorter supply in Traveller universe than you know...

 

[DFW]

Or the SM is totally broken/deliberat SciFi construct. Since it does not even fit the official construction rules I choose that option. One of the (many) reasons I don't play there

So, you constructed a generation method that creates an abundance of perfect worlds??

 

[AndrewW]

I simply play in sectors that DO follow the official rules and strangely those offical sectors have a lot more non-marginal worlds. Another reason why I dislike SM, official material should follow official rules.

There's nothing that says random generation has to be followed to be official.