lunar day


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lunar day

The rotation period (27.322 Earth days) of the Moon, equal in length to the sidereal month. The Moon is thus in synchronous rotation with the Earth. See also libration.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006

lunar day

[′lü·nər ′dā]
(astronomy)
The time interval between two successive crossings of the meridian by the moon.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
It is interesting to note that, although few high lamas that I have met make much use of the cycle of the signs, elements, parkhas and mewas that I shall present (some do), they all seem to depend upon the cycle of the lunar days for creating their practice and teaching calendars.
Time series covered by logbook data The CPCA indicated that lunar day represented only 13.3% of the total variability, although the influence of the lunar day on CPUE was highly significant (permutation test, P<0.01).
Described thus: 'A recapitulation of the changing appearances during the lunar day of the region embracing the mountains designated M1-M5 which are all contained within the south polar circle down to 84[degrees] latitude.
Under constant conditions, crabs had either: (1) a circatidal rhythm in vertical migration with displays at the time of consecutive ebb tides in the field; (2) one display each lunar day at the time of ebb tide in the field or (3) no rhythm.
Powered by the waves, different parts of the artwork light up according to the phases of the moon and will also display the lunar day and the tidal changes.
One lunar day (complete rotation on the moon's axis) equals 27 Earth days, 7 hours, 43 minutes.
After all of this, once the lander softly settles on the moon, 'Pragyaan', a six-wheeled rover will roll out and explore the moon's surface for 14 earth days (1 lunar day).
The solar-powered rover can travel up to 500 meters (yards) and is expected to work for one lunar day, the equivalent of 14 Earth days.
"The day we are going to land is either September 6 or September 7, that day happens to be the beginning of a lunar day. For one full lunar day, the lander & rover will be functioning & carry out scientific experiments," he added.
If the lander and rover survive the fourth lunar night, a fifth lunar day (April 28) of exploration would be possible.
The second day is the 14th lunar day of the dark fortnight - on this day, Lord Krishna destroyed the demon Narakasura and liberated the 16,000 princesses which the demon held captive.
Despite the unresolved glitch, Yutu carried out fixed-point observations during its third lunar day, before it went to sleep again on February 22nd.