Re:GPS will broadcast a 0 second leap second in 128 days. Th...
by swiley on Saturday July 24, 2021 @07:53PM
(#27945395)
I thought GPS time didn't have leap seconds?
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Re:GPS will broadcast a 0 second leap second in 128 days. Th...
by imglorp on Saturday July 24, 2021 @09:09PM
(#27945772)
It does not, but UTC does.
The GPS broadcast contains GPS time and enough information for receivers to obtain UTC from GPS.
> Information in subframe 4 of the NAV message includes the relationship between GPS time and UTC, and it also notes future scheduled leap seconds. In this area, subframe 4 can accommodate 8 bits, 255 leap seconds, which should suffice until about 2330.
Re:GPS will broadcast a 0 second leap second in 128 days. Th...
by detaro on Saturday July 24, 2021 @08:17PM
(#27945521)
And receivers on earth (or at least the humans reading their output) want UTC, so GPS needs to tell them when to add a leap second.
Re:GPS will broadcast a 0 second leap second in 128 days. Th...
by vermilingua on Saturday July 24, 2021 @08:14PM
(#27945511)
GPS time needs many leap seconds, as satellites experience a slower passage of time due to relativity.