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astromark
2009-Nov-20, 10:51 PM
What time is used ?
Is it Florida, eastern coast time. Central or Pacific coast.
From my vantage point in New Zealand its troubling to find I missed the live launch because I was late conecting... :shhh:
I dismantled a clock and glued a clear cd disk to the hour hand with place names appropriately placed around it... so at a glance I see the time zones for you all.
Is the ISS and all space craft Florida based ? Cronalogicly...

mugaliens
2009-Nov-20, 11:14 PM
It's UTC.

UTC (http://en.wikipedia.org/wiki/UTC): Coordinated Universal Time (Temps Universel Coordonne', in French)

GMT (http://en.wikipedia.org/wiki/Greenwich_Mean_Time): Greenwich Mean Time

They're roughly the same, but UTC is very precise. GMT never varies from UTC by more than a second or so. UTC is sometimes (wrongly) called GMT.

loglo
2009-Nov-20, 11:15 PM
What time is used ?
Is it Florida, eastern coast time. Central or Pacific coast.
From my vantage point in New Zealand its troubling to find I missed the live launch because I was late conecting... :shhh:
I dismantled a clock and glued a clear cd disk to the hour hand with place names appropriately placed around it... so at a glance I see the time zones for you all.
Is the ISS and all space craft Florida based ? Cronalogicly...

This article (http://en.rian.ru/world/20081025/117946046.html)says GMT, though it should probably be UTC since they don't do daylight savings changes.

astromark
2009-Nov-21, 03:13 AM
Oh... my poor befuddled mind... Launch and countdown on Cape time from entry into space UTC... They do not use the Florida time.
As you say UTC is as near as, GMT. Then they on board the ISS and Shuttle are 12 hours behind us here in NZ. Thankyou's....:)

WaxRubiks
2009-Nov-21, 05:37 AM
This article (http://en.rian.ru/world/20081025/117946046.html)says GMT, though it should probably be UTC since they don't do daylight savings changes.

GMT doesn't change for daylight saving time....locally we have British Summer Time(BST) in the summer, but GMT is unaffected.

Jeff Root
2009-Nov-21, 07:42 AM
Manned spaceflights launched from the US were on Central Time (which is
my time zone) from Gemini forward, until the destination became the ISS.
Central time because that is where the main astronaut training is conducted
and where the flights were controlled from. There have always been a lot
more controllers in Clear Lake than astronauts in Space.

With the ISS we now have to compromise between Clear Lake and Star City,
and it just happens that Greenwich is exactly halfway between the two.

(Roughly, Clear Lake = Houston, Star City = Moscow, Greenwich = London.
A tale of three suburbs.)

-- Jeff, in Minneapolis

mugaliens
2009-Nov-21, 02:53 PM
The military has been using UTC for decades as it eliminates all confusion with respect to "whose time zone are we using today?" - type questions, particularly when operations cover multiple time zones, and precisely when various command and control agencies are located around the world, as are many units in either training or actual combat.

When all we had to worry about were U.S. crews being controlled from Houston, it made sense to use Houston's time. As Jeff pointed out, it's a lot easier to make three astronauts add or subtract the hour difference than 100 controllers.

On the other hand, when we're dealing with multi-national crews, it wouldn't have made any difference whether Moscow was where it is, or at the same longitude as New Zealand - they would have used UTC.

UTC has long been the "standard" time used for coordinating operations of all types, military, scientific, network/computers, around the globe.