astronomical day


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astronomical day

[‚as·trə′näm·ə·kəl ′dā]
(astronomy)
A mean solar day beginning at mean noon, 12 hours later than the beginning of the civil day of the same date; astronomers now generally use the civil day.
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In the previous work [32], we considered the phenomenon of "palindromes", which stands for a high probability of similar histograms to be found upon comparison of two data series: first, representing the results of measurements of [sup.239]Pu [alpha]-decay over astronomical day (since 6 to 18 h by local, longitude, time) and, second, measured over astronomical night (since 18 to 6 h, in continuation of the first series) and inverted.
The "scattering of the results of measurements" of processes of diverse nature is determined by the earth's motion in the inhomogeneous space-time continuum. The effect of "half-year palindromes"
Thanks to the Earth's erratic rotation, the countdown to 2009 lasted a moment longer as British physicists and official timekeepers around the world inserted a leap second to bring the most accurate atomic clocks in line with the astronomical day.
Sydney's pyrotechnic spectacular is first
CARDIFF A family astronomical day is at the National Museum.
Search for the stars; Check out some space rock and study the stars through the ages in a family astronomy festival at the National Museum in Cardiff. Alison Young reports
The cold weather came despite the spring equinox, seen by some as the first day of spring, when the astronomical day and night are equal.
Weathermen warn: Spring is on hold

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