You are on an airplane flying at a steady \(250 \mathrm{~m} / \mathrm{s}\) at cruising altitude. At noon the pilot announces that you are passing over the center of London and exactly \(6.0 \mathrm{~h}\) later, according to your watch, comes on the address system to say that you are passing over Abu-Dhabi.

(a) Do observers on the ground measure a longer, equal, or shorter time interval between these two events?

(b) Is the difference between the time interval measured on the ground and that measured by your watch detectable?