Is this sort of orbit possible?
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Is this sort of orbit possible?
I'm writing fantasy but I figured you guys would have the best answers for this!
In my solar system, Lucyrion, there are seven planets, but six are in the life-zone. I haven't exactly gone into detail about them all yet, and I've only started thinking about what the orbits may look like - is it possible for all six to be in the same orbit, but at different points? Like.. planet A is to the right of the sun, planet B to the left, but they follow the same orbit (I'm sorry for bad explanations) and the seventh planet is way behind them, out of the life-zone?
Re: Is this sort of orbit possible?
I'm thinking of multiple moons, but even with all of Saturn's Shepherd Moons, I'm still not sure. Speaking of sattelites, there's the multitudes of trash orbiting the Earth. If all those TV and Radio sattelites can stay up there without crashing, that's pretty sweet.
Are all those planets moving at the same speed? They'd all have to be the same size, but with six moons in the same orbital I can't say they'd all squeeze in and not have gravitational effects on one another if they're close enough to the local Sun to be habitable by human standards. Must be small planets.
There's also dual-orbits. They say that Earth's Moon is so big in comparison to its host planet that the two have been astrologicaly considered a dual-planet. Not sure if that fact has been out-of-date yet, my source said "Pluto-Charon" was a planet system, too.
Re: Is this sort of orbit possible?
hmm... okay this is probably going to be an awfully stupid question. But do all planets need a moon? Or could two planets share a moon?
one of the planets is an exact replicable of Earth. Like I said above, I haven't completely thought it all out or written profiles for all the planets yet, but I was hoping to have the other planets a bit smaller.
Re: Is this sort of orbit possible?
In a word-no. The reason a moon orbits is because it is caught in a gravitational well. Of two planets ever got close enough to share a moon, the results would not be pretty. Heck, if you could make out Mars the way we make out the moon here on Earth, it wouldn't be pretty. My best advice is that the Earth-copycat is the main planet. Then it has two moons . Then there is a second planet that has another two moons. Bam, six "planets". Of course, you're the author. You don't really have to explain, if the exact way they orbit the sun isn't crucial to the plot.
Re: Is this sort of orbit possible?
Yeah, the orbit itself isn't important to the plot. I don't plan on going into great detail about it, but I like to know how it works anyways, you know?
Okay so... what if three earth-sized planets were all in one orbit. (a)
And then three slightly smaller planets were all in a different orbit. (b)
(I drew this out but I have no clue how to explain it, so sorry if you find it hard to understand!) Could it be like this: orbit A is horizontal. Orbit B is verticale. They intersect at some points and move at the same speed, but when the planets on Orbit A are closest to the sun, the planets on Orbit B would be further away.
Is that possible? (I hope this made sense! If not tell me, I'll try to make it clearer.)
Again - sorry I'm so naive with this subject! I've never really studied orbits and all that. All help is appriciated :)
Re: Is this sort of orbit possible?
It sounds like you're talking about the planets being the same distance from the sun but with orbits that are at right angles to one another (the a planets vs. the b planets). The problem is that the period of an orbit is dependent upon both the mass of the sun and the distance of the planet from that sun. So they would all have the same year length. Also the habitable zone is where it is neither too hot or too cold for life to form. If the planets in orbit a are the same distance from the sun as those in orbit b then all either are in the habitable zone or all are outside it. Also most orbits aren't perfect circles but rather ellipses with the sun at one focus so the planets in orbit b would be crossing through the space where planets in the a orbit travel, and even if they miss each other a body the size of a planet would cause a lot of disruption. The moon is some 240,000 miles from us and is 2,160 miles in diameter with a mass of 0.0123 earth's and it causes the tides to go in or out. Just imagine what kind of disruption a body with the mass of a planet could cause.
Re: Is this sort of orbit possible?
Two planets can not take up the same orbit. Ever. Orbits change, so they'd eventually end up smacking into each other, and on a cosmic scale that is very, very bad.
What'd I'd say is keep it simple- 6 planets, all in the habitable zone, and the star is unique with it's habitable zone being bigger. No need to get all technical on it.
Re: Is this sort of orbit possible?
Lol I never even thought of an unique star... gosh I'm dense.
That's a whole lot easier than trying to make up some orbital pattern. Thank you!
Re: Is this sort of orbit possible?
Depending on your definition of a planet and the configuration of the star system, this is not correct. There are stable positions in a planetary orbit (simple three-body problem). I suspect that six, however, would be very unstable.
This is one of the things about the system's configuration that I meant. Planets (all bodies, really) pull on each other, so the Lagrange points may not be stable when you consider more than three bodies.
This depends on how hard she wants her sci-fi to be. Getting six planets into the habitable zone (which is small) is pretty much impossible without invoking some artificial construction or a giant planet that has habitable moons (although I'd be very much concerned about the natural formation and stability of such a system), or just breaking the laws of physics.
Re: Is this sort of orbit possible?
That's all very interesting - habitable moons are a possibility, though I'd have to research that a bit more. Do you have any suggestions, other than a unique sun?
Re: Is this sort of orbit possible?
I'm not sure what you mean by unique star. All stellar radiation has to fall off with distance-squared. No matter how you change the energy output, that has to hold. You could make them more massive (more luminous) to increase the range, but the lifetime of a star goes as 1/Mass^(some power greater than one; edit: just googled, looks like 2.5), so there'd be less time for life to evolve on those planets.
From a hard science point of view, what you're asking to do is pretty difficult. I think if you were to take a slightly larger star, put a terrestrial planet at the inner edge of the habitable zone (I suspect that a second terrestrial planet in there wouldn't work, but you could forge ahead and put one on the inner side of the middle anyways), a gas giant at the outer edge, give the giant three inhabitable moons, and put two planets in the L4 and L5 points...that would get you six planets. You could put another gas giant far out and reason that it moved out by launching debris in and that's how the inner gas giant caught all of the rocky material...
That configuration might (doubt it, though) be stable in the longer term, but I doubt that it could form at all. That's a lot of material to order.
But it may at least be close enough to plausible that more people would be willing to suspend disbelief.
Re: Is this sort of orbit possible?
Note that if you place people on habitable moons, you have a very big difference from earth's day/night cycle - and is that something that you (and your readers) want to deal with?
Re: Is this sort of orbit possible?
My characters spend almost the whole book on the same, Earth-like planet. The others are talked about and some visited, but they wouldn't go to the inhabitable moon ones - those would just be talked about. (:
Re: Is this sort of orbit possible?
I personally am bored to death with fantasy novels that try to "explain" the fantastic through known science.
I dont give a rats ass that it is biologially/physically impossible for a creature the size of a dragon to fly - DRAGONS FLY! Give me a flat earth or winters that last many years!
I want my fantasy FANTASTIC!
Re: Is this sort of orbit possible?
Thanks - you guys have all given me a lot of information and stuff to think about. Most of my knowledge of space comes from Star Wars.. and most of that was invented by others. So thanks! :)
@Iasalle202, lol I don't really mind that much. I love a lot of Fantasy that really doesn't explain anything and lets you draw your own conclusions, and I've written that before, and I also love fantasy that explains things uniquely because it makes it seem all the more possible, you know? The book I'm writing right now doesn't really explain most things, the people are magical just because that's how it is, but the MC is boud to ask some questions about how there's life on six planets! :)
Re: Is this sort of orbit possible?
I'm with lasalle202 on that. The trouble is, when speculative fiction tries too hard to "explain" something, it frequently comes across as seeming LESS possible than it otherwise would if they just didn't explain it at all, or explained it by means of something that isn't real in the first place like magic or deities. (I don't know how many times I've wanted to scream at a screen or page with "DNA doesn't work that way!" or the like. Insert just about anything for "DNA" there. :S)
Re: Is this sort of orbit possible?
Magic and tangible deities aren't things we have in today's real world (and the human record of deities is such that pretty much no fiction could match the crazy that's already been thought up), so the rules that the writer gives us are the rules that are apply. But when one starts taking things we have in the real world and arranging them in ways that people "know" (quotes because it's rightly or wrongly; for an example, see communication technology in the ancient through medieval worlds not being accepted in a fantasy novel violate the rules the real world works by, there are issues.
This is one of those times. People know that the habitable zone around a star is small. People know that there is one planet per orbital path. Breaking those rules require explanations. Star Wars had the moon of Yavin IV and we postulate the possibility of life on moons in the solar system, so putting in an inhabitable terrestrial planet around a gas giant will (most likely) be more easily accepted.
Here's how the conversation would go with me (yes, yes, with me)...
"This star system has three Earth-sized planets within the small habitable zone of this small star."
"That's a lot. Where did all the material come from? Our planets are kind of spread out and Earth is, what, as massive as Venus and Mars combined?"
"Yes, but this system is different."
"Different as is not internally consistent and defies the rules of the universe as I understand them?"
"Well, aliens built this system."
"What? How?!"
"The have gravity-manipulation and hyperspace technology. They moved the second two planets from another star system."
"...Okay. Carry on."
This is drastically different than using what you're saying with some human subspecies with gills...
"They have gills?"
"Yes, they breathe through them."
"Gills work underwater, they're on land right."
"Right, but they were modified."
"Uhhh..."
"Genetically. Before the eggs were inseminated. A human corporation did it with alien technology."
"Well...okay."
"See, they took the genes from X and combined them with this stabilization factor that humans bought from the Y traders. The first batch developed gills instead of eyes, so they were tos--"
"Stop, I'm done."
And that's different than.
"They have gills?"
"Yes, they breathe through them."
"Gills work underwater, they're on land right now."
"Right, but they were modified."
"Uhhh..."
"The people on the Isle of Tuorati were going to be killed by a volcanic eruption. They called out to their god Piranou, who reached down to save them. He gave them gills and sped them through the water to get away."
"Oh, that was nice of him. Carry on."
P.S. Seeing a brown-eyed kid that's the child of two people with blue eyes...that bothers me. Also, anything wrong with how space is presented as working (you surprised?).
Re: Is this sort of orbit possible?
Loool now I'm sitting here at 6am trying to figure out if it's plausible for my people to have that sort of technology~
Re: Is this sort of orbit possible?
They had a five-habitable (and one planet-size space station) system in Star Wars. A high-profile place called Corellia (and Selonia, Drall, and dual-worlds Talus and Tralus, and Centerpoint Station). Han Solo was from there. But the reason why it had five worlds was because aliens did use gravity tech to put them there!
Hee.
Re: Is this sort of orbit possible?
STAR WARS<3 Lmfao I'm a huggeeee fan.
Re: Is this sort of orbit possible?
How about a fantasy inside a Dyson Sphere and no I don't mean the vacuum :) Great ball surrounding a sun could encompass several planets etc. Livable inside shell and it would definitely be a unique star
Re: Is this sort of orbit possible?
That's more or less "Ringworld", if you think about it.
Re: Is this sort of orbit possible?
>P.S. Seeing a brown-eyed kid that's the child of two people with blue eyes...that bothers me. Also, anything wrong with how space is presented as working (you surprised?).
Actually it does happen and it's not always the milkman.
Re: Is this sort of orbit possible?
Look up "Kemplerer rosette" in Larry Niven's Ringworld series. It features an example of five worlds in a single orbit.
Unfortunately such a system requires artificial stabilization and equal masses, highly unlikely in a natural system. (It could be that magic holds them into place...)
It is easier to have the planets in different orbits in the life zone. If the planets are small, and there isn't a Jupiter or Saturn sized planet close in, you can fit six or so in the life zone. That number could go up if you had a few double planets.
Re: Is this sort of orbit possible?
This thread broke my brain. o_O
Re: Is this sort of orbit possible?
That's great! Now that you're free of reality you can be a real writer like the rest of us!
*writes about square circles and timecube and how the gubmint is made up of satanic aliens*
Re: Is this sort of orbit possible?
Binary system. Two stars orbiting each other, two around each, and two having figure eight orbits, Or all six orbiting in the 8 fashion, and I'm not sure the specifics, but I think having two suns would significantly increase the Goldilocks zone. Or, it would just move it farther out and not make it any bigger.
Re: Is this sort of orbit possible?
Sometimes the best explanation is no explanation at all. If it's not brought up by the characters then often times the reader overlooks it, or is just more willing to accept it as normal for that universe. An example that comes to mind right now is the planet Namek in Dragonball. It has three suns, which is fine. But it also has no night because the suns aren't together, they orbit the planet or the planet is in the middle of the suns and rotates around giving the appearance they do. Either way, it doesn't matter, because no one in the series questions it and so you just shrug it off and go with it. Heck, it took me a few years to even realize that Namek's trinary system was abnormal.
So yeah, unless you're doing hard Sci-fi, which you've already said you're not, I wouldn't worry about it too much. If this system of yours is normal to your characters, if it's what they know and are used to, then they wont question it, and if they don't then most readers wont, either, so long as you don't draw attention to it.