Kesler Science

Elon Musk: Everything is solar power. The rest is noise. “The sun is about 99.8% of the mass of the solar system. Jupiter's about 0.1% and everything else is in the remaining 0.1%, and we are much less than 0.1%. So, if you burnt all of the mass of the solar system, then the total energy produced by the sun would still round up to 100%. If you just burnt Earth, the whole planet, and burnt Jupiter, which is very big and quite challenging to burn, turn Jupiter into a thermonuclear reactor, the sun is 99.8% of the mass of the solar system and everything else is in the miscellaneous category. Basically, no matter what you do, total energy produced in our solar system rounds up to 100% from the sun. You could even throw another Jupiter in, so we're going to snag a Jupiter from somewhere else, you could teleport two more Jupiters into our solar system, burn them, and the sun would still round up to 100%. As long as you're at 99.6%, you're still rounding up to 100%. Maybe that gives some perspective of why solar is really the thing that matters. And, as soon as you start thinking about things at a grander scale, like Kardashev Scale 2 civilizations, it becomes very, very obvious. I'm not saying anything that's new, by the way. Anyone who studies physics has known this for a very long time. In fact, Kardashev, a Russian physicist who came up with this idea, I think, in the 1960s, just as a way to classify civilizations, where Kardashev Scale 1 would be, you've harnessed most of the energy of the planet, Kardashev Scale 2, you've harnessed most of the energy of your sun, Kardashev 3, you've harnessed most of the energy of a galaxy. Now we're only about 1% or a few percent of Kardashev Scale 1 right now, optimistically. But as soon as you go to Kardashev Scale 2, where you're talking about the power of the sun, then you're really just saying everything is solar power and the rest is in the noise. Like, the sun produces about a billion times, or call it well over a billion times more energy than everything on Earth combined.” All-In Podcast, October 31, 2025