NASA engineer David Oh and his family have moved to Mars time, meaning they need to add about 40 minutes to each day and eat meals at a different Earth time. Oh and his family explain how they have synched their lives to accommodate his job as flight director for rover Curiosity.
There's a sign that hangs outside the Oh family's front door during daylight hours that reads, "Flight Director Asleep... Come Back Later."
The sign is to let visitors know before they knock that NASA engineer David Oh, flight director for the Curiosity mission, and his family are in synch with the Mars rover. They're living on Martian time for the summer.
"When we talk to the rover, we talk to it on Mars time," Oh said. "So, we have to do things 40 minutes later every day."
Earth rotates on its axis once every 24 hours, giving us our definition of an Earth day. But Mars doesn't spin at the same rate, so days on Mars -- known as sols -- are about 40 minutes longer than an Earth day.
Adding 40 minutes to the course of one Earth day isn't a stretch, but try doing it for a week and staying in step with Mars' light-dark cycle.
The whole family -- wife Bryn and their three children, ages 13, 10 and 8 -- is part of the experiment.
"It's great when you're coming home," said David Oh. "It's all dark outside, but your house is all lit up and the kids are there."
It's a red planet vacation without leaving their home near Jet Propulsion Laboratory.
That means meals are served at different Earth times and bedtime is when the rest of the neighborhood is awake, prompting the customized "Do Not Disturb" sign outside the Ohs' front door. Breakfast might be at 3 p.m., lunch might be at 8 p.m. and dinner might be at 2:30 a.m. before it's time for bed.
"When the light comes out and we're going to bed at 1 in the afternoon, you can't really fall asleep," said Braden Oh, 13.
Braden documented his observations on a blog called MarsTimeR -- a thoughtful look at Southern California as experienced on Mars time. The summer-time shift will be coming to an end soon as he transitions from Mars time to something that better accommodates the upcoming school year.
"The city of Los Angeles is really a completely different city at night than during the day," he wrote Monday in his blog. "The weather cools down, the traffic disappears, and you can travel from any part of the city to another in 30 minutes by car."