View Full Version : Rogue Planets

2006-Aug-12, 11:00 AM
If a rogue planet the size of Saturn hit Jupiter would Jupiter easily withstand this impact or would it more likely be thrown out of its orbit? Also would such an impact between two rather large celestial bodies effect Earth? Just wondered. Cheers! :surprised

2006-Aug-12, 11:47 AM
Well, as they say, "the devil is in the details." It all depends. From where does the rogue planet approach? Which way is it traveling? Just logically thinking, if it hits Jupiter from behind, then it will increase the velocity and put the system into an orbit that is further out. If it hits Jupiter going in the opposite direction, then it would slow the system down and put it into a closer orbit. Which could affect the earth. But really, it all depends on the numbers. It's not something that would happen in real life, but for a science fiction story you might consider it.

2006-Aug-12, 04:19 PM
Also it would depend on the velocity of the impact. I can think of two things that could happen:
1. Jupiter absorbs the incoming planet and continues in a different orbit
2. The impact creates numerous proto-planets which fly off in numerous directions.

The combined mass of a jupiter sized planet and a saturn sized planet would not be enough to start spontanous fussion in the core, I think thats about 16 jupiter masses so unless one of the off shoots is a proto planet with a course near to earth, (and you discount the gravitational effect of a new gas giant in the local solar area) I don't think the effect would be that devastating.

2006-Aug-12, 07:39 PM
So Jupiter would easily absorb an impact by a Saturn size object? Though it may ignite into a brown dwarf?

Kaptain K
2006-Aug-13, 01:01 AM
So Jupiter would easily absorb an impact by a Saturn size object?

Though it may ignite into a brown dwarf?

2006-Aug-14, 02:56 AM
The impact (especially at 1% of light speed) would make lots of heat, perhaps 1000 degrees c = 1832 f on the surface which is red hot. It would heat Earth a few degrees when it's new orbit brought it within one astronomical unit a few times per century. Most of the time it would be several astronomical units away in an eliptical orbit. Contrary to the other post, closer orbits are faster, farther orbits are slower. Most impact senarios make the orbit more eliptical, without changing the average speed much. Neil