• Swedneck
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    2 个月前

    again, straight compared to what?

    there is no center of the universe, nor a universal grid that things can reference. one of the most fundamental tenets of astrophysics is that everything is relative and statements like “travelling straight” are simply nonsensical unless you specify what it’s travelling straight in relation to.

    • petrol_sniff_king@lemmy.blahaj.zone
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      2 个月前

      The… Earth and Sun.

      Those are the reference frames.

      You start by traveling with the Earth.
      Gravity “turns off” for you.
      The Earth then curves away as it orbits the Sun.

      You just follow the tangent line.

      • oce 🐆@jlai.lu
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        2 个月前

        Yes, that was my point. I think it aligns good enough with the comics.