Indulging My Astronomy Interests

Despite my general disinterest in the first issue of Rogue Planet, there was one thing that caught my attention, keying in on my interest in how strange fictional planets would actually work. Setting aside that in this case, "alien gods" are probably the correct answer.

Above is the planet in question, floating through the interstellar medium, untethered to any other celestial body. It's cloaked in what seems to be a dense, red atmosphere. All three panels which show the planet from space, it looks basically the same.

OK, so first, it's maintained an atmosphere without any consistent source of external warmth. I was going to say without any source, period, but I started looking online and while the vacuum of space might drop to around -450 Fahrenheit, there is actually stuff in interstellar space. And some of those clouds of dust and atoms can be up to 17 million degrees. I don't know that there would be enough of that to have an appreciable effect, and anytime it wasn't in an area like that, heat would diffuse from the planet back into the void.

Basically, it seems like the planet shouldn't have any atmosphere all the time. Like Pluto, which only has one when it's closest to the Sun, but then freezes and falls to the surface as the dwarf planet moves further away.

But the planet does still emanate heat from its core, and it's probably bigger than Pluto by a fair amount. It's probably at least a Titan or Venus-thickness atmosphere given how invisible the surface is, so putting its size somewhere in that range isn't out of the question. Although if it was a Venus density atmosphere, the crew might be in danger of being crushed by the pressure (although the suits probably could be built to withstand that. There wasn't any mention of high gravity, so probably not bigger than Earth.

So if the planet is generating its own heat, it probably still has an actively rotating core. If it's generating enough heat the planet isn't a frozen ball of ice (which is apparently isn't), it's probably rotating really fast. If the outer crust is keeping pace, that might explain the high winds. Jupiter's a gas giant, so on a much different scale, but it kind of operates the same way.

Rapidly rotating core would likely generate a magnetic field around the planet. Which might explain the auroras that are in the sky in every panel once the crew are on the planet's surface. But auroras on Earth are caused by low-energy charged particles (mostly electrons) from the Sun that slip past or through our magnetic field at the poles and interact with oxygen and nitrogen in the upper atmosphere.

Of course, this planet ain't got no Sun to blast it with electrons. There are charged particles in the interstellar medium, but they're cosmic rays. Which are high-energy charged particles, and don't interact with atmospheric gases in the same manner. They'll give you superpowers (or more likely cancer), but not auroras. Jupiter has auroras that are caused by interactions between its magnetic field and material blasted off from Io by the moon's volcanoes, but this planet ain't got no moon, neither. There's no sign of volcanic activity on the planet, even if it could erupt with enough force to eject material beyond its own upper atmosphere.

It'd be interesting if it was the ship through that was the cause. Particles or material stuck to or carried along with the ship reacting to the atmosphere as they heat up on entry. If there is someone or something waiting for new arrivals, it would even work as a dinner bell or security alarm of sorts. If the sky turns green, that means they've got themselves another pigeon.