

That it reaches its highest point in the sky (noon at your You take very accurate measurements of the sun's movement and determine To the time at 0° longitude, called Coordinated Universal Time Let's look at a more detailed example: say your clock is set For example, if your local solar time differs from another location by 4 To find the longitude, simply compare your local time with the time at a known location and multiply by 15 °/hr. The first of these devices, from English inventor John Harrison,
#World clock honolulu portable
It was not until the invention of an accurate portable chronometer that the problem was solved by using the relationship between time and longitude. Problems in the long history of navigation. Today, every cell phone can tell you the longitude instantly, but historically, finding your meridian was one of the most vexing Remember from the Longitude section that when you move westwardĪcross the IDL the day moves ahead (Friday becomesĪnd when you move eastward across the IDL, the day moves back (Saturday becomes Friday). These rules apply to any location on earth and refer just to the time, not the day - the day has different rules that include reference to the International Date Line (IDL). Remember: eastward is later, westward is earlier. For example, compared to Los Angeles, the time in New York, to the east, is later, while the time in Honolulu, to the west, is earlier. To note in the figure is that, for any location, places to the east have a later time, and places to the west have an earlie r time. The bottom scale on the figure gives the hour difference between the reference time zone centered on Greenwich and locations around the world. If two places are exactly 4 hours apart, how many degrees of longitude separate them?.How can you find your longitude using an accurate clock set.If it is 8 am Saturday in Sydney, what is the time and day in Honolulu?.If it is 3 pm Friday in Honolulu, what is the time and day in Tokyo?.New York? Is the time at these places earlier or later than Hawai'i? In England? Hawai'i and Tokyo? Hawai'i and Los Angeles? Hawai'i What is the time difference between Hawai'i and the Prime Meridian.Are times at places East of your location earlier or later?.What are time zones and how wide are they in ° longitude?.What is the relationship between longitude and time?.Ways to accommodate political boundaries, as shown below. The sky at noon - the nations of the world agreed upon a flexible system of time zones.Įach time zone is 15 degrees wide, but some are stretched in various That wherever you go on Earth, the sun is near its highest point in For continuity in human experience - meaning
#World clock honolulu full
They are based on longitude andĭefined by Earth's rotation, which completes a full circleĭegrees) each day (24 hours). Time zones are another arbitrary societal choice, like the origin point of the Prime Meridian. ToC MAPS Geography Size Latitude Longitude Time Maps New Tools
