How big is Jupiter?

Jupiter provides excellent views in small telescopes like 3 to 4 inch refractors or my 10-inch Newtonian reflector. Easy to resolve as a planetary disk and cloud bands distinct, generally, easy to see, especially if you use planetary filters. However, I pondered this. If Jupiter was placed at 10 pc from Earth, a *good telescope* would need to resolve to about 9.56 x 10^-5 arcsecond size to see the planet :) Jupiter diameter is about 9.56 x 10^-4 AU. I am glad Jupiter is not 10 pc from Earth, otherwise Galileo would never see those tiny lights moving around it :) I can still seem them moving around Jupiter today using my telescopes :) So, while Jupiter looks large in our solar system, Jupiter placed far away will be a tiny size :)
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