What time zone are we in when it's not Eastern Daylight Time? (settling a bet)

IMAGE: Standard time zones of the world as of June 2008 (SOURCE: http://en.wikipedia.org/wiki/File:Timezones2008.png at http://en.wikipedia.org/wiki/Time_zone).

It was about 7:00 PM, Eastern Daylight Time (19:00, local military time), and my sunlit office had begun to dim. I glanced out at the horizon, debating: tear myself away, now, from the proposal I was completing to flick the light switch and grab an Oreo cookie (or three), or polish off my paragraph first? Then the phone rang.

The call was from a couple who had a question: "What time zone are we in when it's not Eastern Daylight Time?"

Easy question. I gave the easiest answer: "It's Eastern Standard Time." However, the more complete answer is layered, like that snack I was salivating about.

[IMAGE: A Double Stuff Oreo Cookie (SOURCE: http://en.wikipedia.org/wiki/File:Happy_Cookie_Friday.PNG at http://en.wikipedia.org/wiki/Oreos)]

Her triumphant "Right answer!" and request to repeat it to her spouse signalled there was more to their matter. My guess: they needed help settling a bet.

She mentioned that he'd cited "something about military time." As he's a US Naval Academy alumnus and sailor, he was probably referring to Zulu Time or Coordinated Universal Time (UTC). Harold F. Maybeck does a fine job of explaining the origin and use of Z- or UTC-time here.

They wanted a hit-and-run answer, so for that time being, I opted out of addressing military time and email time. Instead, I shared that I'd previously blogged about time zones and promised to email the posts. I'll be sure to include this one to help even the odds.

(Afterward, I'll strike a light and scarf some sandwich-cookies.) ###