Lunar Standstill - Direction of Moonrise and Moonset and Altitude of Moon at Culmination

Direction of Moonrise and Moonset and Altitude of Moon At Culmination

The azimuth (direction) of moonrise and moonset varies according to the time in the moon's nodal period of 18.6 years. For a northern latitude on earth of 55° the following table shows moonrise and moonset azimuths for the moon's narrowest and widest arcs across the sky. The azimuths are given in degrees from true north and apply when the horizon is unobstructed. Figures for a time midway between major and minor standstill are also given. Widest arc for full moon is generally achieved at midwinter and narrowest at midsummer. For new moon (when it near the sun in the sky) widest arc is in the summer, as for the sun.

Azimuth of full moon on horizon
narrowest arc widest arc
epoch moonrise moonset moonrise moonset
minor standstill 124° 236° 56° 304°
midway 135° 225° 45° 315°
major standstill 148° 212° 32° 328°

For observers at latitudes not too close to the equator or a pole, the Moon is highest in the sky in each period of 24 hours when it culminates on crossing the observer's meridian. During the month, these culmination altitudes vary so as to produce a greatest value and a least value. The following table shows these altitudes at different times in the lunar nodal period for an observer at 55° latitude. The greatest and least culminations occur about two weeks apart.

Altitude at culmination
epoch greatest least
minor standstill 53.5° 16.5°
midway 58.5° 11.5°
major standstill 63.5° 6.5°

The following table shows some occasions of a lunar standstill. The times given are for when the moon's node passed the equinox—the moon's greatest declination occurs within a few months of these times, depending on its detailed orbit. However, the phenomenon is observable for a year or so on either side of these dates.

Times of lunar standstill
major standstill minor standstill
May 1988 February 1997
June 2006 October 2015
April 2025 March 2034
September 2043 March 2053

Read more about this topic:  Lunar Standstill

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