Like fossil fuels come from organic matter that grew because of the sun. Is there any form of energy on that cannot be traced back to the sun in some way?
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Where did the Sun’s energy come from?
The gravitational collapse of a cloud of mostly hydrogen in the vacuum of space.
And anything falling together under gravity was given that kinetic energy from somewhere* and ultimately it can all be traced back to the Big Bang.
As for where that energy came from, it’s possible we’ll never know. Most organised religions (and no doubt a few disorganised ones) have their theories, of course. You may subscribe to one of these.
* This is the principle most commonly simplified as “what goes up, must come down”
What’s really interesting is that “what goes up, must come down” doesn’t hold at the scale of the universe. A naive thinker might imagine big bangs happen in cycles, but in fact this doesn’t appear to be the case, because space itself is expanding faster than galaxies are falling back together. And it’s not just faster now, but it’s accelerating! At some point, space will be expanding faster than the speed of light, and because of that, the entire universe will disappear from our view.
Despite that, the Milky Way galaxy is still close enough to the Andromeda galaxy that they’ll collide in about 5 billion years, so don’t worry, there’s still interesting things to come! If you want to see it, though, you’ll need to be somewhere other than Earth, because by that time the Sun will have advanced in its life cycle enough to render Earth completely uninhabitable by all known forms of life.
Just to add onto this comment, it’s thought that the Sun is slowly getting hotter and more energetic as it gets older and in approximately 1 billion years, the Sun will be hot enough to render the Earth uninhabitable for life as we know it.
In approximately 5 billion years, the Sun will reach the end of its life and expand into a red giant, swallowing up Mercury, Venus and potentially Earth in the process. Interestingly, once the Sun reaches this phase of its life, it could potentially warm up some of the outer moons enough for them to have liquid water, if they can hold onto an atmosphere of course.
Someone please correct me if I said anything wrong, I’m just a casual space nerd and not a professional astronomer.
Ran we starlift the Sun to make it last longer?
What does “lift” mean in this context? A web search turns up a Doris Day musical from 1951 which is kind of funny to think about but I’m guessing is not what you mean.
As for the general case of modifying the Sun - or any star - in some way, it’s all but certain to need a huge number of resources (or amount of energy, or both), and considering the Sun is on the order of a million times larger than Earth, far more than can be obtained from Earth alone.
I mean, I’d like to be proven wrong and there’s some exotic-physics way of causing the helium in the Sun to spontaneously turn back into hydrogen, but if that was easy, you’d expect that we’d see stars do that by themselves occasionally. We don’t, which implies there would still need to be some kind of energy input required to get it started.
Without exotic physics, we’d pretty much need on the order of the energy that the star had output from birth up to that point, and if we had that, we’d be better off using that energy in other ways.
We could get all Earth life off Earth and into a self-sustaining, space-faring habitat with a minuscule fraction of the resources. We might be better off aiming for something like that.
https://en.wikipedia.org/wiki/Star_lifting
any of several hypothetical processes by which a sufficiently advanced civilization could remove a substantial portion of a star’s matter which can then be re-purposed, while possibly optimizing the star’s energy output and lifespan at the same time
Everyone is giving you some great answers, but there are since more subtle ones worth mentioning too.
When you take a picture of space, the light from those other stars hits the camera sensor and induces a tiny electrical charge, which is captured, amplified, and analyzed to create the image. Your eyes actually work that way too.
It’s not an energy source as you typically think of it; it never powers anything, but technically it is* energy that exists on Earth that didn’t come from our sun.
Almost.
- Nuclear energy comes from natural materials of the earth that arrived in their current form (it is basically recycled supernova energy from long long ago)
- Geothermal comes ultimately from the gravitational energy of the earth itself compressing and heating it
Literally every other energy source (edit: aside from tidal and some others that people pointed out) is some form of modified and stored sunlight, in some way or another.
There is also kinetic energy when objects in space crash into the earth. RIP 🦖🦕
Hypothetically those would average to O as they strike randomly though right?
Well it’s still incoming energy, and it’s a scalar quantity. One could argue that average velocity/momentum incoming from the strikes might be zero, but I don’t think that’s the case either
Yeah, AFAIK the big meteor showers all come from the “oncoming” direction as Earth orbits the sun. That actually might average out to zero linear momentum, depending on how they’re spaced, but it definitely is reducing the Earth’s angular momentum around the sun.
