>>11147284First of all, the observable universe, which probably isn't even all of the universe, just the sphere of perspective we can witness is gargantuan, with a radius of 46,508,000,000 light-years from the focus of Earth.
Of this sphere of the universe, with a volume of 4.21*10 light-years, we haven't even explored 1%, we've only formally explored within our solar system (and not even all of it). If you include the use of astronomy as exploration, then the furthest confirmed exoplanets are SWEEPS-04 and SWEEPS-11, both 27,710 light-years away. If we take this as the radius of a sphere, then the "volume" of astronomical exploration is, at most, 8.91*10 light-years , only 0.0000000000000000211638954869359% of the observable universe.
>End of part 1. 
