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Name: David
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A

With a heat factor which is expanding, and therefore gas compression and molecular restructuring, which is said to have occurred -igniting our sun, is it a possibility, over time, Jupiter could emerge or ignite as a star?

I think the only way that this would be possible is if jupiter was able to consume a good deal more mass. Without an ample enough food source, I believe it will stay as it is and the fusion process will not occur. Astronomers have already found objects outside our own solar system that are larger than jupiter, but that appear to just be planets. The theoretical limit is something around 80 times the current mass of Jupiter. So indeed, the food source would need to be quite large(or perhaps it would then be better to think of Jupiter AS the food source for the other object). And even if an object has enough mass, it also requires that enough of the mass is in a small enough area at the same time. So, 80 times as massive, and hot and dense.

However, all that aside, Jupiter already shines! It just doesn't happen from the fusion process. I believe Jupiter already radiates more energy(most of it in the infrared spectrum) than it receives from the sun. Now, that's really not terribly surprising when you think of the fact that A) all those winds, storms, and (compared to earth) immense gravity on Jupiter are going to give off energy and B) even though Jupiter is large relative to the other planets, this is offset by its distance from the sun.

For the truly ambitious, you can listen to Jupiter! Jupiter radiates at around 20MHz I believe. There are fairly simple kits available from NASA (and I believe the plans/schematics are free) that will allow you and your students to listen to Jupiter. Look up "Radio JOVE" for more details.

Michael S. Pierce
Materials Science Division
Argonne National Laboratory


Jupiter does not have anywhere near the mass needed to form a star. The Sun has about 99.8% of the mass of our solar system in it and Jupiter contains most of the rest. That being said, the sun is still 1050 times heavier than Jupiter. The mass needs to be very high so that fusion can start and Jupiter would need to weigh a minimum of 80-100 times what it currently weighs in order to start fusion.

Matt Voss


While it is nice to imagine an era with two suns (me being a fan of Arthur C. Clarke) Jupiter simply does not have enough mass to sustain a fusion reactor in its core. Think of it this way, a fusion reaction (which is what powers a star) is an explosion, the heat from the reaction will cause the proto-star's matter to expand away from the reaction. Thus, the nuclear fuel (hydrogen, deuterium, tritium) would actually get blown away from the explosion. The reason a star can sustain a nuclear reaction (keep the fuel within the reacting core) is that its mass compresses the atoms at its core so that an equilibrium between the nuclear reacting core and the expansion of the heated matter is formed. Jupiter is 1/80th the mass of the Sun, it simply does not have enough mass to keep a nuclear fusion reaction going.

Greg (Roberto Gregorius)

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