An astronaut takes what he measures to be a \(10-\) min nap in a space station orbiting Earth at \(8000 \mathrm{~m} / \mathrm{s}\). A signal is sent from the station to Earth at the instant he falls asleep, and a second signal is sent to Earth the instant he wakes. Does an observer on Farth measure the astronaut's nap as being shorter than, longer than, or equal to \(10 \mathrm{~min}\) ?