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How many timezones are on the Earth?

It's New Years eve and my friends and I are debating: how many time zones are there on Earth? I say that there can't be more than 24 time zones, but my buddy says there are more. Seems like that'd define how many times New Year is celebrated each year.

Dave's Answer:

What an interesting question. You're right that the logical answer to the question is 24: there are 24 hours in a day and it's also how long it takes for the Earth to rotate once around.

But then again, that seems too easy.

Sure enough, a quick check of the National Oceanic and Atmospheric Administration site reveals that there are actually a rather staggering 30 different time zones on Earth.

Timezone / Time Zone Map of the World Globe Earth

Yes, you read me right. In addition to the usual 24, there are fractional time zones:

Offset from UTC	Location
+3.5	Newfoundland Time
-3.5	Iran
-4.5	Afghanistan
-5.5	India
-6.5	Burma
-9.5	Mid Australia

UTC = Universal Time Coordinated, by the way, the modern update to what used to be called Greenwich Mean Time.

Many people believe that India has multiple timezones, and some folk even suggest that they have 15-minute timezones, but according to NASA:

India spans almost exactly two time zones, but their government decided that they wanted one time for the entire country. Their solution was to split the difference between what the time would be if they used two zones. So, Instead of the time being 10:00 in Bombay and 11:00 in Calcutta, the time is 10:30 in both places.

I think this is the basis of the Chicago song lyric "Does anybody really know what time it is, Does anybody really care, If so I can't imagine why..."

Oh, and Happy New Year, where-ever you are!

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Categorized: d) None of the Above (Article 8679)
Tagged: new years celebrations, time zones, trivia
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Comments

I thought this one would be a tooo long article considering you started gathering info on it from the last 2days :) [@twitter messages!]

Posted by: Amit Bhawani at December 31, 2008 9:32 AM

"10:00 in Bombay and 11:00 in Calcutta, the time is 10:30 then" ... LOL ... This is very funny. It looks the decision was taken by two statisticians :D

Posted by: Paul at December 31, 2008 1:29 PM

You may laugh at the India timezone, but it's a very practical solution and of course it is much easier for a country to run on one (or few) timezone.

Posted by: Dempsey at January 1, 2009 6:52 PM

Those are the usual time zones, but there are also a few odd ones that have 15 minute offsets. I knew of the one in Australia so went off looking, and found there are three. I found this to explain it better:

http://www.worldtimezone.com/faq.html

Posted by: tvkelley at January 2, 2009 1:50 PM

what time zone is Bermuda in and what is it called?

Posted by: giacomo at October 11, 2009 8:31 PM

Giacomo, I did a Google search for "what timezone bermuda" and found this right on the search results page:

Bermuda
Mar 29, 2009 ... What time zone is Bermuda in? Bermuda Standard Time - AST (Atlantic Standard Time) is 4 hours behind Greenwich Mean Time (GMT-4). ...

So there ya have it. :-)

Posted by: Dave Taylor at October 11, 2009 10:30 PM

I have something to say, now that you mention it, but ...

I do have a lot to say, and questions of my own for that matter, but first I'd like to say thank you for all your efforts on this Web site by buying you a cup of coffee!

I do have a comment, now that you mention it!