Hi John, › Forums › Jupiter › Minimum aperture for seeing GRS? › Hi John, 1 February 2018 at 2:59 pm #579032 Paul G. AbelParticipant Hi John, In the past I was able to make it out easily in a 4 inch telescope. In the last few years, I have seen it without too much difficulty in a 90mm refractor. The use of a W#80 (light blue) helps to make it easier to see. Cheers, -Paul
