If a Planet of Earth's size were to rotate around A jovial planet of Jupiter size; Is it possible?

Question

This is for my story; An earth sized moon is orbiting a jovian like planet. I'm wondering how big (radius) of the orbit around the jovian planet would be; and if it is possible.

Thanks

Silver

Answer 1

Of course it's possible.

Further, if the jovian sized planet was at... say... the orbit of venus or so, the earth sized planet might be capable of bearing life.

I say further in towards the sun, because the orbit of the earth sized moon around it's parent planet would eclipse a significant portion of sunlight as it passed behind it's parent.  Thus it would require a larger amount of sunlight to get about the same sunlight we get here on Earth.

This, of course, assumes that the life on that moon would be about the same as ours and the plant life would use photosynthesis.

Answer 2

Science fiction story? Thats cool... Im picturing a Halo: Combat Evolved sky... without the giant ring.

Since this planet is Jovian like and not specifically Jupiter you could make up any number of characteristics such as magnetic field and distance from star to make the Earth sized moon livable, which is what I assume you are trying to do.

The mass doesn't matter when it comes to orbits, and you can put the moon any distance from the planet so long as it isn't skimming the gas giants atmosphere or to far out to actually orbit. Callisto is pretty big for a moon and it has an orbital radius of nearly 2 million km.

If you do want the moon to be livable the magnetosphere of the planet will be an issue. Van Allen bets are pockets of radiation around planets with magnetic fields, but since you are designing the planet you can decide where they are and how they affect said moon.

Answer 3

yeah, its possible. but the mass of the 2 planets would cause that to make a big circle sort of like the way pluto and its moon sort of revolve around each other (pluto's moon is roughly half the size it is.

Answer 4

it IS possible...

Answer 5

Yes. In the last few years astronomers  are discovering that nearly any thing goes. There are Jovian size planets orbiting less than 1au from their Sun. These and other discoveries have caused astronomers the rethink present theories of planet formation.

Answer 6

It's definitely possible, as the mass of the smaller body doesn't really affect the radius of the orbit. As the radius increases, the satellite (Earth-sized moon in this case) will decrease in linear velocity / orbital period. (meaning that it will take longer to orbit the jovian planet)

If your jovian world is anything like ours, then you would want to be sure that your moon is far enough from it so that it isn't getting fried by radiation trapped in the gas giant's magnetic field. For comparison - our space probes can get fried by the radiation near Io, Jupiter's innermost large moon.

Plus, the further out it is, the smaller the gas giant is in the sky there, and the shorter the eclipses are, so less sunlight gets missed.

Answer 7

Sure it's possible.  But things would be radically altered in the solar system.  Lots of other things orbits would necessarily have to change.

Answer 8

Could it?  Sure.  There is nothing that would prevent such a thing.

As to how far that is a matter of orbital mechanics.  Mass and speed of orbit determine the orbital distance.  There could be many stable orbits but tweaking those 2 numbers.

Maybe someone here will do the calculations for you. ;-)

Answer 9

It would work exactly the same as it does with us and our moon and all of the other planets with moons. What makes you think physics changes just because you change the size of the components? Every planet-moon pair is a binary system in orbit about the sun. Look at the orbits the Earth and Moon individually make around the Sun and you will see that even though the moon is in orbit around the Earth (if the Earth were stationary in space without a sun, the moon would follow a circular or eliptical path around the Earth.), the path it follows (likewise the Earth follows) around the sun is a wavy elliptical path with the waves being opposite to each other. The moon alternately speeds up and slows down to overtake and pass and then fall behind the Earth. At all times, the moon travels in the same direction relative to the sun as the Earth does, all it does is speed up and slow down relative to the speed of the Earth. However, if you ask people to draw the orbit of the Earth and Moon on paper, the majority will draw the moons orbit as a series of loops around the Earth, which if you think on it, means the moon must stop and go the opposite direction and physically, this can not happen. Think of it this way, two cars speeding down the freeway. One car stays in the center lane of three. The other comes up from behind, moves into the left lane and passes, only to swing in front and then over to the right lane and then falls behind and then swings back over to the left lane and then do it all over again. At no time does the 2nd car reverse direction, but it is in orbit about the car in the center lane. Plot the path of both cars, and you will see something similar to the orbits of the Earth and Moon about the Sun. So, really, it matters NOT about the size of the moon in a binary pair in orbit about the Sun. Your only problem is determining which is the planet and which is the moon. By convention, it is the larger, denser one which is the planet, and the smaller being the moon. By the way, the smaller the moon, the more likely it WILL be making loops around the planet and actually be moving backwards relative to the orbit about the Sun. The reason is the magnitude of the attraction, which would keep a moon in orbit and not be lost to capture by the sun as it literally slows to a stop and goes backwards. Our moon does not do this because it is so BIG and we form a stable binary pair.