As the title says. I’m actually thinking about this hard with my friends because everything that’s produced on Earth stays on Earth so it doesn’t change size, but what if it’s not from Earth but it stays on Earth?

  • groet@feddit.de
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    7 months ago

    > energy equals mass

    That doesn’t mean energy has a weight.

    It means it is physically possible to transition energy to mass and vice versa. Sunlight hitting the earth does not add any weight.

    Edit: turns out that part was wrong

    Also, earth radiates heat out to space. At a rate of (aaaaaaaaalmost, because of the greenhouse effect) 100% of the energy we get from the sun. If it didn’t, earth would be a few million degrees hot by now…

    • sushibowl@feddit.nl
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      7 months ago

      That doesn’t mean energy has a weight.

      No, it literally does mean that. If you put light in a box of mirrors the total weight of the box will literally increase by an amount equal to the energy of the photons. If you put some radioactive material in a theoretically perfectly sealed box from which no heat or light could escape, and weigh it while it decays into radiation, the weight will not change.

      This applies to all forms of energy. A spring is heavier when compressed. An object gets heavier when you spin it, or heat it up. Sunlight hitting the earth most definitely makes it heavier. In fact, the sun hits the earth with about 4.4*10^16 watts of power, corresponding to about 0.5 kilogram per second.

    • ccunning@lemmy.world
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      7 months ago

      Oooh…Good point. And now I have conflicting responses.

      This one makes the most intuitive sense to me but ¯\_(ツ)_/¯

      • mexicancartel@lemmy.dbzer0.com
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        7 months ago

        One more thing to connect both responses.

        Energy itself doesn’t have mass. Mass is interchangeable. But we do gain mass by a very kittle amount when it is stored (by plants or solar panels you know). So both answers checks out. Mass can be converted to large amount of energy and large amount of energh can be converted to little amount of mass.

    • purplemonkeymad@programming.dev
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      7 months ago

      Energy don’t have weight but, it does have an effect on the curvature of space the same way matter does. In fact one of the proposed methods to create artificial blackholes is to put enough photons into the same place. It’s easier than getting matter together as photons don’t interact with eachother.

      However the point is correct that light energy will only impart an insignificant amount to the earth’s pull.