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Moon Phase
CURRENT MOON Waning Gibbous
97.9%
The Sun Now
Time Zones
Sydney
2:03 am
Perth
12:03 am
Auckland
4:03 am
New York*
12:03 pm
Paris*
6:03 pm
GMT
4:03 pm




Moon Phase



CURRENT MOON




Wednesday, 16 April 2014
16:03 GMT

Phase name: Waning Gibbous
Illumination: 97.9%
Age: 16.1 Days
   
Full moon: Tuesday, 15 April (07:45)
Last quarter: Tuesday, 22 April (07:53)
New Moon: Tuesday, 29 April (06:17)
First quarter: Wednesday, 7 May (03:16)
Full moon: Wednesday, 14 May (19:18)



Lunar and Solar Activitiy For The Coming Week
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Moon Phase Rise & Set Times Twilight Times
Date
(midnight)
Phase name
Illumination
Moon
Rise Set
Sun
Rise Set
Civil
Begin End
Nautical
Begin End
Astronomical
Begin End
Tuesday
15 Apr 14
Full Moon
99.9%
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Wednesday
16 Apr 14
Full Moon
99.5%
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Thursday
17 Apr 14
Waning Gibbous
96.7%
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Friday
18 Apr 14
Waning Gibbous
91.7%
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Saturday
19 Apr 14
Waning Gibbous
84.4%
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Sunday
20 Apr 14
Waning Gibbous
75.4%
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Monday
21 Apr 14
Waning Gibbous
65%
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Tuesday
22 Apr 14
Last Quarter
53.8%
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All times are displayed in GMT

Twilight is before sunrise and again after sunset. There are intervals of time, twilight, during which there is natural light provided by the upper atmosphere, which does receive direct sunlight and reflects part of it toward the Earth's surface. Some outdoor activities may be conducted without artificial illumination during these intervals, and it is useful to have some means to set limits beyond which a certain activity should be assisted by artificial lighting. The major determinants of the amount of natural light during twilight are the state of the atmosphere generally and local weather conditions in particular. Atmospheric conditions are best determined at the actual time and place of events. Nevertheless, it is possible to establish useful, though necessarily approximate, limits applicable to large classes of activities by considering only the position of the Sun below the local horizon. Reasonable and convenient definitions have evolved.

Civil twilight is defined to begin in the morning, and to end in the evening when the center of the Sun is geometrically 6 degrees below the horizon. This is the limit at which twilight illumination is sufficient, under good weather conditions, for terrestrial objects to be clearly distinguished; at the beginning of morning civil twilight, or end of evening civil twilight, the horizon is clearly defined and the brightest stars are visible under good atmospheric conditions in the absence of moonlight or other illumination. In the morning before the beginning of civil twilight and in the evening after the end of civil twilight, artificial illumination is normally required to carry on ordinary outdoor activities. Complete darkness, however, ends sometime prior to the beginning of morning civil twilight and begins sometime after the end of evening civil twilight.

Nautical twilight is defined to begin in the morning, and to end in the evening, when the center of the sun is geometrically 12 degrees below the horizon. At the beginning or end of nautical twilight, under good atmospheric conditions and in the absence of other illumination, general outlines of ground objects may be distinguishable, but detailed outdoor operations are not possible, and the horizon is indistinct.

Astronomical twilight is defined to begin in the morning, and to end in the evening when the center of the Sun is geometrically 18 degrees below the horizon. Before the beginning of astronomical twilight in the morning and after the end of astronomical twilight in the evening the Sun does not contribute to sky illumination; for a considerable interval after the beginning of morning twilight and before the end of evening twilight, sky illumination is so faint that it is practically imperceptible.

Twilight definitions courtesy U.S. Naval Observatory.

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