Q:  How much farther away could the star be placed
                    and still yield the same S/N when observed by ELT?


                If ELT collects 29.5 times as many photons as JWST,
                    then it could achieve the same signal-to-noise
                    when observing a star 1/29.5 as bright
                    (since the two telescopes would then collect the
                     same number of photons per second).

                How far away would a star have to be moved to drop
                     to 1/29.5 of its original intensity?

                                       2
                      ( orig distance )         1
                      ( ------------  )   =   -----
                      ( new distance  )        29.5


                    -->  new distance  =  5.43  times original distance