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What Time Is It on the International Space Station? (2013)

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Re: What Time Is It on the International Space Station? (2013)

#31
post #24
post #3

Earlier quoted context omitted.

Unlike Britain, Iceland does not have Daylight Saving Time, and therefore is GMT+0 throughout the year.

Am I the only programmer who is suddenly super duper envious of Iceland?

DST should not be the only reason to use UTC. It's probably just what makes it obvious once a year that someone uses timestamps wrong.

Re: What Time Is It on the International Space Station? (2013)

#32
post #14
post #4

I find it somewhat interesting that when SpaceX's streams switch to views with burned-in timecode it is always in UTC. Edit: and usually in ISO8601-ish format

If you are going to design something using a time code the most obvious solution is probably to choose your own zone. When you realize that doesn't apply to anyone else, UTC is the next option. Especially because it means you don't need to deal with user configuration. As for ISO8601, that probably results from people looking for some standard to help with compatibility. If you just mean YYYY-DD-MM HH:MM that is just…

Well, the T can be omitted if reading and writing parties agree: »NOTE: By mutual agreement of the partners in information interchange, the character [T] may be omitted in applications where there is no risk of confusing a date and time of day representation with others defined in this International Standard.«

And I think SpaceX wouldn't even have the obvious option of using their own time zone. AFAIK mission control and launch are in different time zones anyway, so UTC is really the only sane option to make sure everyone refers to the same time.

Re: What Time Is It on the International Space Station? (2013)

#33
post #2

It's weird that the author chooses Iceland as an example of a GMT+0 country, rather than Britain which is where Greenwich is.

This is an old article since iOS has added UTC time zone to system settings and clock app. Android still doesn’t support UTC time zone, and need to use Iceland as hack. Which depends on Iceland not changing their time zone.

There are probably better choices than Iceland, if Android supports them. Iceland doesn't do DST now, but has in the past (1917-1918, and 1939-1968). The farther North a place is, the stronger the case for DST, so I wouldn't count on Iceland changing not their mind someday.

I'd pick someplace reasonably close to the equator. Then there is little difference in sunrise and sunset times throughout the year, and there is pretty much no case to be made for DST on sunlight grounds.

Some good choices, if whatever you are trying to set supports any of them:

• Liberia. City of Monrovia if you have to specify by city. There's only 0:43 difference between the longest and shortest daylight periods of the year there.

• Guinea, city of Conakry.

• Togo, city of Lomé.

There are a few other countries in the general area of these three that are on UTC+0 but these three have never had DST so are probably more likely to stay that way.

Re: What Time Is It on the International Space Station? (2013)

#34
post #11

Earlier quoted context omitted.

I thought UTC the same, doesn't that mean that GMT+0 is essentially wrong? I thought GMT was essentially UTC+0, and all other time zones (ignoring DST) are defined as offsets to UTC, not GMT.

Think of it as two pointers referencing the same data: Time* UTC = Time(0); Time* GMT = *UTC; *UTC == *GMT; // True UTC == GMT; // False

Your example with pointers actually wouldn't compile, and I think the analogy you are trying to make is not accurate. On the second line you are assigning the target address of `GMT` to be the value pointed to by UTC. In other words you are trying to assign a value of type "Time" to an object to type "Pointer-to-Time".

If, however you meant for that line to be: Time *GMT = UTC;

it would compile fine, but then your second comparison would evaluate to true, and the whole analogy be rather pointless.

Re: What Time Is It on the International Space Station? (2013)

#35
This kind of makes me want to make a site that will show the current solar time of the ISS. i.e. when the ISS is between the Earth and Sun it's 12:00, on the opposite side it's midnight. And show what time sunrise and sunset are. The minutes would obviously be much shorter (as a day is only ~90 minutes long), but it'd be interesting to see.

Re: What Time Is It on the International Space Station? (2013)

#36
post #33

Earlier quoted context omitted.

This is an old article since iOS has added UTC time zone to system settings and clock app. Android still doesn’t support UTC time zone, and need to use Iceland as hack. Which depends on Iceland not changing their time zone.

There are probably better choices than Iceland, if Android supports them. Iceland doesn't do DST now, but has in the past (1917-1918, and 1939-1968). The farther North a place is, the stronger the case for DST, so I wouldn't count on Iceland changing not their mind someday. I'd pick someplace reasonably close to the equator. Then there is little difference in sunrise and sunset times throughout the year, and there is…

> The farther North a place is, the stronger the case for DST

I disagree. If you get to the north pole or anywhere near the Arctic Circle (where Iceland is), it can still be dark at noon in the winter and light at midnight in the summer. You can't nearly compensate for that with a mere hour change, so why bother?

Re: What Time Is It on the International Space Station? (2013)

#37
post #12

Earlier quoted context omitted.

This is an old article since iOS has added UTC time zone to system settings and clock app. Android still doesn’t support UTC time zone, and need to use Iceland as hack. Which depends on Iceland not changing their time zone.

Had anyone here tried to live life with their iPhone on UTC?

UTC as a world clock is a happy medium, and works well. You get it in the notifications tray.

Re: What Time Is It on the International Space Station? (2013)

#39
post #14

Earlier quoted context omitted.

If you are going to design something using a time code the most obvious solution is probably to choose your own zone. When you realize that doesn't apply to anyone else, UTC is the next option. Especially because it means you don't need to deal with user configuration. As for ISO8601, that probably results from people looking for some standard to help with compatibility. If you just mean YYYY-DD-MM HH:MM that is just…

It’s yyyy-mm-dd not yyyy-dd-mm....

You are totally right, I got that wrong :( sadly it's to late to either edit or delete my shame.

Re: What Time Is It on the International Space Station? (2013)

#40
post #4

I find it somewhat interesting that when SpaceX's streams switch to views with burned-in timecode it is always in UTC. Edit: and usually in ISO8601-ish format

I work in the space industry and UTC is the only things we use for anything operational. Most also use it for meeting coordination. Many missions also use a Mission Elapsed Time which is based on launch time. Usually only used during launch and early phase in case there are launch delays.
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