← Back to context Comment by card_zero 2 days ago Tidal power doesn't come from the sun either. It slows the earth's rotation by a tiny amount. 4 comments card_zero Reply OtherShrezzing 2 days ago Is the origin of that rotation not also the gravitational wells created by the Sun? HappMacDonald 2 days ago IIUC it's only half from the Sun's gravity well, the other half of that energy gradient is from the Moon's gravity well.Also IIUC "energy from the sun" is really shorthand for "Energy emitted by solar fusion", which tidal would not involve. Smithalicious 2 days ago The laws of gravity are entirely symmetric, so it doesn't seem fair to attribute it specifically to the sun; also, the energy in this case is coming out of the "v" in earth's good old 0.5mv^2 kinetic energy relative to the sun. card_zero 1 day ago Good pedantry, but then we can argue that the origin of fossil fuels is geothermal (if we ascribe the origin of life to hydrothermal vents).
OtherShrezzing 2 days ago Is the origin of that rotation not also the gravitational wells created by the Sun? HappMacDonald 2 days ago IIUC it's only half from the Sun's gravity well, the other half of that energy gradient is from the Moon's gravity well.Also IIUC "energy from the sun" is really shorthand for "Energy emitted by solar fusion", which tidal would not involve. Smithalicious 2 days ago The laws of gravity are entirely symmetric, so it doesn't seem fair to attribute it specifically to the sun; also, the energy in this case is coming out of the "v" in earth's good old 0.5mv^2 kinetic energy relative to the sun. card_zero 1 day ago Good pedantry, but then we can argue that the origin of fossil fuels is geothermal (if we ascribe the origin of life to hydrothermal vents).
HappMacDonald 2 days ago IIUC it's only half from the Sun's gravity well, the other half of that energy gradient is from the Moon's gravity well.Also IIUC "energy from the sun" is really shorthand for "Energy emitted by solar fusion", which tidal would not involve.
Smithalicious 2 days ago The laws of gravity are entirely symmetric, so it doesn't seem fair to attribute it specifically to the sun; also, the energy in this case is coming out of the "v" in earth's good old 0.5mv^2 kinetic energy relative to the sun.
card_zero 1 day ago Good pedantry, but then we can argue that the origin of fossil fuels is geothermal (if we ascribe the origin of life to hydrothermal vents).
Is the origin of that rotation not also the gravitational wells created by the Sun?
IIUC it's only half from the Sun's gravity well, the other half of that energy gradient is from the Moon's gravity well.
Also IIUC "energy from the sun" is really shorthand for "Energy emitted by solar fusion", which tidal would not involve.
The laws of gravity are entirely symmetric, so it doesn't seem fair to attribute it specifically to the sun; also, the energy in this case is coming out of the "v" in earth's good old 0.5mv^2 kinetic energy relative to the sun.
Good pedantry, but then we can argue that the origin of fossil fuels is geothermal (if we ascribe the origin of life to hydrothermal vents).