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Show older comments. Sarvesh Kumar on 27 May Vote 0. Commented: Sarvesh Kumar on 17 Jul Accepted Answer: jonas. The difference between 2 consecutive GPS time is 60 sec. I have been trying to convert this 6 digit numbers stored in variable 't' to HH:MM LT format storing it in variable t2 using various examples and codes on this forum and from YouTube but have so far failed.
Therefore, every weeks, or The first epoch was the start count, 6 January , the second was 21 August , the next epoch is 6 April This is known as the GPS week number rollover issue. This means that the GPS week number rollover for the receiver will take place exactly Other GPS receivers allow a message to be sent to the receiver to adjust the epoch start date manually.
In this manner, provided a new epoch start date is periodically set, a rollover will be avoided. This allows weeks or years between week number rollovers. The U. The control center periodically coordinates the atomic clocks of each GPS satellite. UTC time is linked to the rotation of the Earth. This rotation is not constant, in fact it is generally slightly slowing, and can be affected by events such as Earth quakes.
Periodically, leap seconds are introduced to keep UTC time within one second of the Earths rotation time. Unfortunately, UT is not a uniform time scale because Earth's rotational period is on average gradually increasing.
The change is primarily due to tidal friction between Earth's oceans and its rocky mantle through the gravitational attractionof the Moon and, to a lesser extent, the Sun. This secular acceleration gradually transfers angular momentum from Earth to the Moon.
As Earth loses energy and slows down, the Moon gains this energy and its orbital period and distance from Earth increase. These decade variations are attributed to several geophysical mechanisms including fluid interactions between the core and mantle of Earth.
Climatological changes and variations in sea-level may also play significant roles because they alter Earth's moment of inertia. The secular acceleration of the Moon implies an increase in the length of day LOD of about 2.
Such a small amount may seem insignificant, but it has very measurable cumulative effects. At this rate, time as measured through Earth's rotation is losing about 84 seconds per century squared when compared to atomic time.
Derived from TAI, the length of the UTC second is defined in terms of an atomic transition of the element cesium and is accurate to approximately 1 ns billionth of a second per day. Because most daily life is still organized around the solar day, UTC was defined to closely parallel Universal Time. The two time systems are intrinsically incompatible, however, because UTC is uniform while UT is based on Earth's rotation, which is gradually slowing. In order to keep the two times within 0. The orbital positions of the Sun and Moon required by eclipse predictions, are calculated using TD because it is a uniform time scale.
World time zones and daily life, however, are based on UT[2]. In order to convert eclipse predictions from TD to UT, the difference between these two time scales must be known. In particular, hundreds of eclipse observations both solar and lunar were recorded in early European, Middle Eastern, and Chinese annals, manuscripts, and canons.
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