What prevents the gas giants like Saturn and Jupiter from firing up as a nuclear furnace and becoming a star?

Answer 1

The answer to this lies in the understanding of what causes stars to ignite. I think its that there's a critical mass beyond which the gravity is strong enough to create the pressures and densities to begin the fission (or fusion) reaction that powers the sun. Look at the mass of the sun versus Saturn or Jupiter, keeping in mind that our sun is not considered the smallest type of star. So something smaller than our sun could ignite, but we assume Jupiter is not about to. Also, how much hydrogen is there on Jupiter or Saturn? I just read recently, that while a star burns by converting H to He, it also converts a small amount of He to something denscer and so on.... But much beyond that the energy given off trying to fuse (or fiss) the larger atoms doesn't give off enough energy to keep a star burning. So the presence of a LARGE amount of hydrogen is essential to igniting a body like Jupiter.

Answer 2

A star has a very large mass whereas; its gravity is so strong that it causes Hydrogen molecules to combine causing helium. This is called fusion.

Saturn and Jupiter don't have enough mass to actually start the fusion process.

In many ways we say Jupiter and Saturn are huge planets and that is just it, planets that are compared with the size and mass of Earth.

Compared to our sun they are very small.

For example all the mass of our solar system (everything planets etc) added together only comprise 5% of our solar system mass. The other 95% is just our sun.

Answer 3

Stars are formed under immense gravity, gravity greater than that of Jupiter or Saturn. Jupiter and Saturn are examples of what are reffered to as 'Brown Dwarf'. Starts that simply never got large enough to initiate the thermonuclear reaction.

How it works, basicaly, is that once a ball of gas such as Jupiter attains enough mass (Critical Mass), the gravity sends the atoms bouncing off eachother so hard that they stop bouncing off and start fusing togeater. The energy released speeds up the atoms around it and they start moving faster and bouncing harder too and acheives a chain reaction.

Answer 4

outline 'hit something'. Earth is a strong body with a surrounding environment. As you enter the ambience from area the density of air receives better and better, yet because Earth isn't vast sufficient to carry a very thick environment there's a unexpected transition to the sturdy floor of the planet. Jupiter is plenty better vast. that's so large that as you enter Jupiter's environment the density will enhance, only because it does on earth, yet you may bypass a lot deeper. Density and rigidity only keep on increasing and extending. ultimately the molecules in the ambience are so densely packed they're easily a liquid state. keep going and the liquid turns into denser and denser until eventually perchance, on the middle, that's virtually sturdy. in spite of the indisputable fact that, there is not any unexpected swap from one state to the different, only a comfortable gradient of density foremost from tenuous gasoline to sturdy middle. there is not any floor to talk of, yet that does no longer propose there is not any sturdy middle. [Edited to the contact upon the Shoemaker-Levy 9 result question in the subsequent answer: The comet ought to no longer have punched with the help of the planet because that is only too dense. A comet is not any better than a lose mass of rock and ice, nowhere close to as dense as Jupiter. on the speeds the impacts exceeded off it doesn't be required to hit a sturdy mass to provide an explosion. undergo in ideas that products expend in our own artmosphere each and each and every of the time, from time to time exploding lengthy before they attain the floor.]

Answer 5

The Sun is almost one thousand time larger in volume than Jupiter. There simply isn't enough pressure for atoms to collide in the core.

Answer 6

Size. Jupiter would have to weigh 13 times as much to create enough pressure to fuse hydrogen.

Answer 7

They are not large enough to Begin nuclear fusion If some how they were to combine into on planet it may start nuclear fusion and turn to a sun.

Answer 8

Just not big enough to have enough gravity to ignite a fusion reaction.

Answer 9

not big enough, they are giant only compared to the earth, a planet, not a star.

Answer 10

Insufficient mass.