Why do comets leave a path of ice in its wake? Isn’t that a similar idea?

This article is an absolute mess:

"Rolls-Royce Holdings is getting into the nuclear reactor business"

RR have been in the nuclear reactor business since the late 50s and their first home grown reactor went critical in 1965.

"Rolls-Royce Holdings announced in 2021 its intent to develop nuclear reactor technology, having obtained $600 million in public and private funding to develop its business"

That money was for small modular reactors (SMRs), small terrestrial power stations completely unrelated to microreactors.

What are the Vegas odds for the first manned Mars landing being done in a Rolls?

TRISO fuel among other safety advances mean that dangers due to a failed launch are massively limited compared to a few decades ago.

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Sorta, we have indeed measured our motion and the motion of the galaxy against the CMB. That's the biggest "rest state" we can measure against.

Gonna make urban combat with super mutants and radscorpions way more dangerous though

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At a surface level: No. If you're imagining, say, a firework and the trail it leaves, with "sun-stuff" behind it - there's nothing like that. This has been covered in detail by other posts.

At a more detailed level: Yes-ish. The Sun is constantly emitting particles - not just massless light but also massive particles, the "solar wind". As the Sun (and the entire solar system) move through space, this creates a "wake" or elongated "bubble" called the heliosphere. Notably, this is much larger than just the Sun - all the solar system's planets are well inside the heliosphere. This diagram demonstrates the effect.

The heliosphere is invisible and undetectable to the naked eye or any "human-level" interaction; you need special equipment to detect the differences between it and the surrounding interstellar medium. From a human perspective they would both "feel" just like empty space.

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It applies to everything. If you fix earth in one universal place, the sun revolves around the earth. Nothing really makes sense, because there are phantom accelerations everywhere (because a more truthful model makes the sun stationary, since it is the much larger object, and experiences less acceleration than the earth does) but aside from those phantom accelerations, which are all real accelerations that the earth is experiencing, which we are applying to the rest of the universe to force earth to stay still, all the other math still checks out.

Not so much a blaze of fire, but the Sun does shoot out particles constantly (mostly electrons and protons) in the solar wind. There's also solar flares, coronal mass elections, and solar energetic particle events that occur rather frequently.

The Sun does have a heliosphere, though, and it interacts with the interstellar medium (yes, there is a non-trivial amount of mass in the spaces between stars). Heliopause occurs when the pressure of the solar wind matches the pressure of the interstellar medium (at about 100 AU).

As the Sun travels through this interstellar medium, it leaves behind a heliotail that is the direction opposite the Sun's motion in the galaxy.

https://en.m.wikipedia.org/wiki/Heliosphere

I see! Thanks for the explanation!

there is a heliotail, which is a comet-like tail that is inflated by the solar wind of particles streaming off the sun, but it's more of a tail of the entire solar system than just streaming behind the sun like you might be thinking.

Post below asks “why nuclear all of a sudden? Partly because the technically well-informed have finally (inevitably )!come to the correct conclusion that there is no route to a decarbonized economy without nuclear power. Renewables are great, renewables are the future, but nuclear power absolutely is going to be part of the solution.

As far as their connection to space travel, nothing else can match the energy density of nuclear power. There’s just no getting around it, if we limit ourselves to chemical fuel the rest of the solar system is essentially off-limits to anything biological

Well, in a way maybe - but not like you think. It’s called the Solar Wind and it shoots out equally in all directions (usually) rather than leaving a path. It’s not fire(there is no fire on the sun) but it’s ionizing & non-ionizing radiation of many different types.

Kinda sorta. Charged particles being emitted from the sun creates the heliosphere.

It does apply to earth. All motion is relative to something else. How fast are you going right now? You may be sitting still and think, I’m not moving at all. Ok, but the earth is spinning, so now how fast are you going? Ok, but the earth is also rotating around the sun. It’s also part of the solar system, which is moving, but it’s also part of the Milky Way, which is moving. But it also is part of the universe, which is expanding. So how fast are you going? The only way to answer it is to measure your speed “relative” to another object

No. As others have said. The sun isn’t on fire and space is mostly empty, nothing pushing on the sun to leave a trail behind it.

This doesn’t apply to Earth right? Especially since it does move - by revolving around the sun

The anti-nuclear groups are losing funding thanks to the collapse of the Soviet Union and Russia is a big part of it. Also, the anti-nuclear groups were largely ignorant and manipulated baby boomers who are dying off.

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No, the sun and the material in it does not feel any affects of the motion. As far as the sun and planets are concerned, there is no "ahead" or "behind" for the motion.

* For the nit-pickers out there: yes, there is tiny (and I do mean tiny) effect from galactic tides.

Why are our attitudes towards rocketing nuclear material into the stratosphere and beyond all of the sudden changing from "absolutely not" to "this is fine"?

There isn't a medium that the sun is moving through, nothing is dragging on its material like would produce "waves of fire" in its "path". The movement is imaginary- only real when you're measuring relative to other objects. No motion is universal, this is the big revelation of Einstein's theories of relativity.