Time zones in North America. The eastern part of the United States is offset by 5 hours from Universal Time. The central part of the USA and most of Mexico is 6 hours different from UT, while the West Coast is 8 hours different.
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When it is noon where you live, it is midnight on the opposite side of the world. Usually when we think of time, we mean "the time of day where I live". If we say something happened at 9 AM, we mean it was morning a while after sunrise (in most places in most seasons). If we plan to meet someone at 6 PM, it might be for dinner in the evening around sunset (once again, depending on the season and the latitude of our location).
However, there are times when something happens that isn't related to the time of day in just one place. This is often true for astronomical events like eclipses or meteor showers. Astronomers use a special time scale called Universal Time (UT). People around the world can convert a time expressed as Universal Time to their own local time zone. Sometimes that time will be in the morning, or maybe late at night. Sometimes it will even be on the next day!
Universal Time is based on the time of day in England. If you learned that a meteor shower was going to happen at noon UT, you would know that the Sun would be high in the sky if you were in England. You wouldn't be able to spot most meteors. If you were in the Americas, the local time would be sometime in the morning... so the meteor shower might be visible from where you live if the Sun hadn't risen yet (for example, in California). In China, it would be evening... a pretty good time for viewing meteors. People in Siberia and New Zealand would be in a great place to see meteors, since it would be midnight there.
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