Daylight saving time in the air and in space

Daylight saving time (DST) ends Sunday at 2 a.m. locally. Nearly all in the United States enjoy an extra hour of sleep while our cell phones, computers and a lot of other gadgets silently update themselves. But not all clocks need to be changed because they do not observe daylight saving.

In space and on other planets, daylight saving isn't very useful. Vehicles like the Mars rovers, or closer to home in geosynchronous satellites such as the GOES weather satellites that send data back to the WRAL Weather Center, keep track of time internally. Spacecraft event time” (SCET) is kept by onboard computers, recorded as ticks relative to when the spacecraft clock was started. Those ticks vary in length from spacecraft to spacecraft but all are converted to UTC for use by scientists.

The airline industry also operates using UTC. This prevents confusion as aircraft move between time zones and as they continue to fly during the 2 a.m. "fall back" end of daylight saving. Though pilots and passengers are not machines, daylight saving time still exists in our day to day lives.

Paul Ryder, resource coordinator for the Air Line Pilots Association and a captain flying the Embraer 145 for ExpressJet explains “pilot rest periods are adjusted according to DST changes to maintain passenger safety and compliance with federal requirements. Airlines also closely track DST at the destinations they serve to provide accurate flight schedules for passengers."