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Rocky Jupiters

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Gregory:
I opened the new button to create a new simulation, and I selected a random exoplanet, the planet's name is HD 74156 c, it is nearly 8 x the mass of Jupiter and 1.64x Jupiter's radius as shown here, it is believed to be one of the largest planets known, but, somehow, it has a rocky texture, I'm starting to believe that rocky Jupiters exist, though they must be very rare, if it's a bug, then it must be a cool one, if rocky Jupiters exist, then Jupiters with extreme densities must be terrestrials, making them extreme Mega Earths, and after all, Kepler-10 c was once believed to be the first Mega Earth discovered, and it's only 2.35 x Earth's radius, but thought to have an astounding 17.2 Earth masses, more than Neptune.
Kepler-22b's is large too, but we're not sure whether it's terrestrial or neptunian, it could be both.

Here's a screenshot of HD 74156 c, it's radius is 113645 km, while Earth's mean radius is 6371 km, so HD 74156 c is much bigger than Jupiter, and yet it's rocky, pretty weird.

Gregory:
Also, an unusual planet, Kepler-432b, was discovered orbiting a red subgiant, the planet is 45% bigger than jupiter in radius and 6 times more massive, so it's the densest planet ever discovered.

Here's a simulation of Kepler-432b, a blue ocean terrestrial Earth like look of the planet was chosen due to the extreme density and consistency of the planet, yet its rotation period is 30 minutes long because of its extreme density.

Darvince:
Once a gas giant reaches a certain point, between the mass of Jupiter and Saturn, they start becoming more and more dense until fusion begins in the star. So what you are seeing with the density of these objects is simply gravitational compression from the weight of all the gas, and since gas is incredibly compressible, it has formed a dense object. This can also be seen with red dwarf stars, which have very high densities, in fact if you choose Wolf 359 and place it in the sim, you will note that its density is near 30g/cm3. Much higher than any rocky planet. Kepler-432b is simply a super Jupiter and could likely have a large rocky core compared to other super Jupiters, giving it its higher density.

If a rocky Jupiter were to exist, its density would most likely be several hundred grams per cm3, far surpassing the density of even the two objects you posted in this thread. It would also be much smaller than Jupiter despite having similar pass and its surface gravity would be horrifically high.

Plasmic Physics:
There are at least two things that bugs me about this part of the physics simulator:
1. Astronomical bodies convert to gas giants above a mass of 13.00 Jupiters, despite having a iron/silicate composition containing no hydrogen whatsoever, and having no atmosphere.
2. Such a giant planet manages to generate it's own heat through nuclear fusion, even though silicon requires significantly higher pressure to achieve nuclear fusion than hydrogen; furthermore silicate planets don't normally contract nearly fast enough to produce sufficient heat to induce fusion. Depending on how fast a giant silicate planet grows, it should either glow for a while as it converts directly into a black dwarf, or it should glow brightly before exploding in a nova, leaving behind a white dwarf.
3.The appearance of a black dwarf as in the US2, is not simply a black star. That is a cheap shortcut.

Gordon Freeman:
There... aren't any black dwarves in US2. That's a bug.

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