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If Saturn was a Star!

  1. Jan 25, 2007 #1
    What would happen if Saturn had become a second Sun in the formation of our universe? Would earth have ever come to the way it is now? What would happen if it all of a sudden became a sun this very instant?

    All comments are appreciated!
    Last edited: Jan 25, 2007
  2. jcsd
  3. Jan 25, 2007 #2


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    I'm confused by what you mean by "stage". Are you implying that Saturn would now have the same mass? Still orbiting?...
  4. Jan 25, 2007 #3
    Never mind that... I edited it out, it didn't make too much sense.
  5. Jan 25, 2007 #4
    Well, first Saturn would have to be massive enough to become a star in the first place, which would mean it would have to be at least 8% the mass of the Sun. In that case, the barycenter of the Sun-Saturn system would be around .7 AU away from the Sun, meaning our summers would be MUCH hotter and our winters MUCH colder.

    For Saturn to become a star at its current mass would involve "magic," so we won't consider it. :)
  6. Jan 27, 2007 #5
    because our seasons are caused by..?
  7. Jan 27, 2007 #6
    I doubt "seasons" would be defined by the Earth's tilt at that point. It wouldn't compare to the temperature change caused by moving between .3 AU and 1.7 AU away from the sun... :rolleyes:

    Also, I've made the assumption that we'd still orbit the barycenter of the solar system. That may not be possible if Saturn was massive enough.
  8. Jan 29, 2007 #7
    Note that the orbit of present day will not be stable due to the chaos of the system.
  9. Feb 7, 2007 #8
    I'm aware your question regards Saturn but one thing I use to keep hearing is that 'Jupiter was nearly a star' which was always as quickly dismissed (this idea was even played on in 2010). If I'm not mistaken, Jupiter would have had to have been at least 10 times its current mass to have become a brown dwarf (though its radius would have remained approximately the same). The difference between brown dwarfs and large gas planets is that gas planets have a metallic core and the outer layers of gas remain seperate; with a brown dwarf, the metallic core mixes with the various gas layers through convection, material rising to the surface, cooling, and returning to the centre (on a side note, fusion in lower mass brown dwarfs doesn't necessarily take place, brown dwarfs bigger than 13 Jupiter masses fuse deuterium and those bigger than 65 Jm fuse deuterium and lithium). In order for either Saturn or Jupiter to have become brown dwarf stars, there might have been a need for at least 10-15 times as much material orbiting the sun as the solar system formed, I imagine this would have had some effect on the formation of the other planets.

    Considering the idea of Jupiter being a brown dwarf star is a nice idea though as the various moons such as Europa and Ganymede would warm up, the ice would melt and atmospheres might form. The fact that the temperature of a small brown dwarf is in the range of about 900 to 1500k means the moons shouldn't be obliterated as the would by a regular star capable of fusion. It would be interesting to think of what would become of Io. In this case, not only would our solar system have 2 suns but we would have something that resembled a mini solar system within our own.

    Last edited: Feb 7, 2007
  10. Feb 7, 2007 #9

    George Jones

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    Is the subjunctive mood dead? :rolleyes:
  11. Feb 7, 2007 #10
    Whoa hold on there for a sec, steve. Even if Jupiter were a brown dwarf Europa and Ganymede wouldn't produce no more of an atmosphere than they already have. For Europa and Ganymede is nothing more than chunks of ice and if they were to melt it would just be another complete seaworld in space.
  12. Feb 7, 2007 #11
    Europa's atmosphere probably wouldn't change much because of its weak gravity but Ganymede, which is 3/4 the size of mars, has a gravity slightly greater than Titan (1.428 m/s^2, Titan is 1.35) and a magnetosphere & Ionosphere, might go through quite a change. Terretrial observations have suggested that Ganymede may have a substantial amount of oxygen trapped under the surface which might be as large as the atmosphere on Mars.
  13. Feb 11, 2007 #12
    A flaw with that movie (2010).. if you could build self replicating machines that eat a planet..

    (aside: and that is not so far away as you think.. all you need to do is build a machine that can eat a rock.. oh, and also self replicate)

    ..anyway.. if you had such a machine and you wanted to light a small solar system, it would seem much more efficent and safer to build a bunch of fusion power stations to power a bunch of sunlamps that you aim ONLY at the planets you want to heat. These could be massive zeppelin like constructs floating in the atmosphere of the gasgiant.

    So lets just discuss what the planets would be like if they were heated.
    Doesnt jupiter emit a lot of radiation? Perhaps some hundreds of meters under water on europa would be best bet.
  14. Feb 11, 2007 #13


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    It wasn't a flaw. The monoliths weren't eating the planet, they were adding mass to it by duplicating themselves from an extradimensional source - the monoliths are stargates to elsewhere. The extra mass caused it to begin collapsing, which is what we saw.
    Last edited: Feb 11, 2007
  15. Feb 11, 2007 #14
    Well that's much more environmentally sound.. ;)

    Is there a better thread for this? Im afraid I have dragged us off topic.
  16. Feb 12, 2007 #15


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    It's only off-topic if the OP isn't sufficiently answered before we digress.
  17. Feb 12, 2007 #16
    what do you mean?
  18. Feb 12, 2007 #17
    ok.. I interpreted as eating the planet because in the movie they noted jupiter losing its chemical stain.

    I still think that if you have self reproducing machines then building sun lamps would be a much more efficient approach and environmentally friendly approach
  19. Mar 2, 2007 #18

    Hi, Stevebd1. Hypothetically, would some of the melted ice evaporate to form clouds (provided that there were enough oxygen traped under the surface), reducing the sea’s volume? It has silicate rock under there somewhere. Do we know that there aren’t rock formations relatively close to the surface of the ice crust i.e. did Galileo’s data include all of Ganymede's surface area, or did it miss some when it passed? Thanks.
    Last edited: Mar 2, 2007
  20. Mar 6, 2007 #19
    According to data obtained from the Galileo mission, Ganymede consists of a differentiated structure- a large lunar sized 'core' of rock & iron overlain by a deep layer of warm soft ice capped by a thin cold rigid water ice rich crust. If the surface temperature was to rise and the ice begin to melt, rather than there being rocky formations, Ganymede would probably become a sea world (possibly with the polar caps still frozen, depending on how much the temperature was to rise). As the core is estimated to be moon size, this would put it well below the surface of the new ocean. The following links should be of some use-



    Last edited: Mar 6, 2007
  21. Jan 8, 2012 #20
    I was wondering if it was possible that the 4 gas giants formed from a second much smaller sun that went supernova??? would they have enough mass between them??? I remember reading how it is more common for duel star systems.
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