The Jupiter/Saturn as stars theory

[SpaceCommanderNemo]

Alright, so I was listening to a conspiracy podcast today and as usual, it got the gears turning. For reference, it was The Higherside Chats (http://thehighersidechats.com/conspiracy-podcast-thc-114-robert-morningstar-extraterrestrials/), an interview with Robert Morningstar. Possibly a nut, I never know with these guys... Anyway, he was talking a bit about how Jupiter and Saturn used to be suns/stars. After some googling the theory, I was left a little bummed. A history of alien contact and a prehistoric Earth with three suns would be waaaay more interesting than this boring one, but I digress...

First of all, Jupiter, the larger of the two, would need much more mass to generate nuclear fission. This means that, no matter the highly flammable materials in it's atmosphere, sustained heat production on the level of a star would be highly unlikely...

BUT.

Because of the elements found in the atmospheres of Jupiter and Saturn, it would have taken them both significantly longer to cool down after forming than the other, solid planets.

So...

Is it possible... if either Jupiter and Saturn were both very very small stars or previously significantly warmer than they currently are... that the habitable zone of our solar system could have been altered enough to explain the potential past habitability of Mars? Titan? Europa? Even if not full fledged stars, could the superheated gasses that comprise their atmospheres have once radiated enough heat to keep Jupiter and Saturn's now icy moons in a tropical state?

Either way, I think I'm going to try to fire up PlanetFactory and make me a solar system like the theory suggests. Flying from kerbin to a lush, green duna... gravity-braking around a very hot jool to land on a tropical laythe... Imagine the scenery!

[randomness5555]

Is it possible...I couldn't say. I have no idea how you would check for something like that without carbon dating (or whatever equivalent you use for a sun)

How would this work in PF? Replacing Jool with another sun?

[Skyler4856]

Perhaps if I converted the hydrogen inside of Jupiter/Saturn into an element, even neutron based, reactions that which is more easily fused, perhaps even a denser isotope of hydrogen, could lead to sustained fusion.

[SpaceCommanderNemo]

How would this work in PF? Replacing Jool with another sun?

Pretty much, I guess. I'd also duplicate it, for a Saturn analogue. I guess I need to figure out if making Jupiter and Saturn stars (of not much greater size than they are now) would have any effect on their gravitational pull. Would they orbit each other, like in a binary star system?

Duna could have oceans, the second star would also have at least one laythe-like moon, and Dres would be a lot more like Moho. Despite likely being a desert wasteland, Dres would have quite the view. I'd put Vall on a spin and add a Callisto analogue, tidally locked to Jool. It would, at some points, pass between the two stars, but one side would experience mostly darkness the rest of the time.

I guess I just want some scientific possibility behind the idea before I go to all the effort... I'm like that. Otherwise there's no point to melting ice on a moon that would just freeze up again.

[Camacha]

I have been tinkering with the idea of Jupiter gathering enough mass to form a double star, as a lot of systems seem to have those, but I do not consider it an actual possibility within our own. It would pretty much go against everything we know about star formation.

That does not mean it is not true, but it makes it highly unlikely.

[Scotius]

I don't see how could it work. Jupiter was too small to even become brown dwarf. Maybe just after formation it radiated a lot of heat, but it was way too early to allow for tropical paradise on its moons.

[YNM]

Even the largest of these planets, Jupiter - that holds more than 2x all the other planet's masses combined - can't overcome the Coulomb force of hydrogen nucleus just by the pressure and temperature in it's core; This is a key to ensure you have continuous, not runaway, nuclear fusion. Of course, you can add outer force, but (I bet) the results won't be a star, just a small SN Ia that have weird emission / absorption lines, plus the fact you just blow a planet up.

If you ask me like in some theoretical exams of astronomy regarding a star with the mass of Jupiter, and you want it's physical data, I can calculate it - I have done it for Jupiter. I can do the same for much other bodies, given for inside-KSP-system I know the rules.

Jupiter still radiates more energy than what it (should) reflects from the Sun, presumably left-over heats from it's formation - this effect is most visible in radio and microwave wavelengths.

Edited June 24, 2014 by YNM

[Brotoro]

...Possibly a nut, I never know with these guys...

Yup. Definitely a nut.

[Twreed87]

Possibly a nut, I never know with these guys...

Looking at that site, I'm pretty sure every single person involved in it is an absolute nut.

[peadar1987]

I assume a second star beyond the orbit of Mars would make things a lot more difficult for life in the solar system. Instead of minor seasonal variations in temperature caused by axial tilt and orbital eccentricity, you would have huge variations between being in conjunction and opposition. Jupiter orbits at about 5 times the distance from the sun than earth does, so the distance between earth and Jupiter varies between 4 and 6 AU. As the power received from a star varies with the square of the distance, that means that in conjunction, you get 2.25 times more energy from Jupiter than at opposition.

The lower limit for a red dwarf star is about 75 Jovian masses. Let's assume Jupiter is replaced with a star this size. The surface temperature of such a star would be about 2,500K. The sun's surface temperature is about 6,000K. Radiative power scales with the fourth power of temperature, so the amount of radiation per unit frontal area from our potential red dwarf will be about 1/33rd that of the sun.

However, the sun has a far greater frontal area than a red dwarf, about 100 times, in fact, so the actual radiation reaching a target the same distance away will be about 1/3300th that of the sun.

So it turns out I was wrong, if Jupiter turned into a red dwarf, it would not actually have a massive effect on the temperature of earth at all.

[/stream-of-consciousness-post]

[Scotius]

Additionally, during conjunction sun!Jupiter's glare would greatly complicate things for astronomers It would be next to impossible to see most of the stars. On the other hand, bright nights would make lives easier for everyone else (except people that can't sleep while light is on).

[peadar1987]

I assume a second star beyond the orbit of Mars would make things a lot more difficult for life in the solar system. Instead of minor seasonal variations in temperature caused by axial tilt and orbital eccentricity, you would have huge variations between being in conjunction and opposition. Jupiter orbits at about 5 times the distance from the sun than earth does, so the distance between earth and Jupiter varies between 4 and 6 AU. As the power received from a star varies with the square of the distance, that means that in conjunction, you get 2.25 times more energy from Jupiter than at opposition.

The lower limit for a red dwarf star is about 75 Jovian masses. Let's assume Jupiter is replaced with a star this size. The surface temperature of such a star would be about 2,500K. The sun's surface temperature is about 6,000K. Radiative power scales with the fourth power of temperature, so the amount of radiation per unit frontal area from our potential red dwarf will be about 1/33rd that of the sun.

However, the sun has a far greater frontal area than a red dwarf, about 100 times, in fact, so the actual radiation reaching a target the same distance away will be about 1/3300th that of the sun.

So it turns out I was wrong, if Jupiter turned into a red dwarf, it would not actually have a massive effect on the temperature of earth at all.

[/stream-of-consciousness-post]

On the other hand, out at Jupiter, Europa orbits at 0.0044 AU. This means that it will get pretty darn hot. Europa is 227 times closer to Jupiter than earth is to the sun. This means that, even though Jupiter would be 3300 times less bright than the sun, Europa would receive a proportion of Jupiter's energy 51,529 times greater than the proportion of the sun's energy that the earth receives. This means that overall, Europa would see Jupiter as being some 15 times brighter than the sun over earth (for comparison, Mercury, at its closest approach to the sun, sees it as being about 11 times brighter than from earth).

In order for a Jovian moon to experience the same power from Jupiter as earth gets from the sun, it would need to be 57 times closer to Jupiter than earth is to the sun. This is an orbit of 2,624,000km, significantly further out than Callisto, the outermost Jovian moon (1,882,709km). Incidentally, this means that Callisto would receive about the same amount of energy from Jupiter as Venus does from the sun. Toasty!

*Disclaimer for outrageously quick and nasty calculations...

[SpaceCommanderNemo]

So lets say I've got this...

Will Duna's orbit be effected? Will Dres get captured the orbit of the binary system? Is it possible for a binary system like that to orbit another star? What the heck happens to the objects caught in the orbit of the binary system? I can't seem to find the right diagrams to explain it through google or wikipedia... How big would the stars have to be to make this work? Would I have to push their orbit out farther to keep them from interfering with the entire orbital system?

Edited June 25, 2014 by SpaceCommanderNemo

[YNM]

One would need their masses and distances to determine whether the system is keplerian or non-keplerian. If the binary component holds the same mass as the single star component, they would orbit each other like a binary system, and the four planets (purple, blue, red, gray) could orbit the barycenter instead. Planets around the binary component may not orbiting the barycenter, due to the same reason.

Also, a silly thing would be that the objects orbiting the barycenter(s) will have the same period, despite different distance. Still can't calculate the appropriate state through...

Edited June 25, 2014 by YNM