New answers tagged time
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What are the twinkling stars in the New Horizons Arrokoth approach?
Those are actually a visual artifact known as "jitter". It is caused by the motion of the spacecraft as it travels through space. The motion causes the light from the stars to appear to &...
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How exactly is UT1 measured/calculated?
("How exactly is UT1 measured/calculated?" -- with "interest in fine details about how UT1 time is measured.")
"UT1" is a standard measure of time currently close to mean ...
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Moonrise and Moonset time in Sydney vs Perth
Yes. The Earth isn't flat. Sydney and Perth are at different longitudes, so the when the moon rises in Sydney, it is is still set in Perth. The moon rises earlier as you go towards the East. So the ...
- 104k
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Modified Julian Date (MJD)'s epoch is 0:00 on November 17, 1858 (JD − 2400000.5) has fewer digits than JD. But what's so special about November 1858?
But what's so special about November 1858?
Nothing, other than that was when JD 2400000 occurred. Look at all of the zeros! The next time we'll see that many zeros will be noon on August 31, 2132.
It ...
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Modified Julian Date (MJD)'s epoch is 0:00 on November 17, 1858 (JD − 2400000.5) has fewer digits than JD. But what's so special about November 1858?
Nothing special occurred on that day, except that it was 2400000 days after January 1, 4713 BC proleptic Julian calendar. That latter date is significant as it year 1 in the solar, lunar and ...
- 104k
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