Strangely, I CAN get it on my 4 footer, in Michigan. The Q is 37% on the CS8000 meter. Typically a Q of 15 is good enough for viewing. The answer is "it depends" .
ken I could get it reliably on a 5' c-band dish, back when it was on 72W. I haven't tried it since they moved the signals to 87. I do have one 7.5' dish parked on it, which does a good job.
Now that it is on 87W, adjacent satellite interference might be an issue. I get it currently with a 6 ft Fortec motorized with a 87 signal (Coolsat 5000). However the NASA feed channel on the same sat is just marginal.