August Full Moon on Columbia River

[coolchange]

If this shows up it is a picture of the recent (August 3) full moon taken about 10 PM while sitting on my Albin27 at Government Island in the Columbia River...nice evening

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[DCatSea]

Fabulous - lucky you.

[MadMoney]

Great pic for sure!!

Anthony

[DesertAlbin736]

Very nice. Could almost be mistaken for a sunrise. It's difficult to capture a full moon rise & do it justice compared to what it must have looked like in real life. Down here at latitude 33 & no daylight savings time this week actual sunset is at 7:23 PM MST. And of course a full moon rises right after sunset.

There are three types of twilight: Civil, Nautical, and Astronomical. At my location Civil twilight ends tonight at 7:49 PM, Nautical twilight at 8:21 PM, and Astronomical twilight at 8:55 PM.

Ever wonder what those definitions mean? I wondered too, so I looked it up. According to NOAA:

In its most general sense, twilight is the period of time before sunrise and after sunset, in which the atmosphere is partially illuminated by the sun, being neither totally dark or completely lit. However there are three categories of twilight that are defined by how far the sun is below the horizon.

Civil Twilight:
Begins in the morning, or ends in the evening, when the geometric center of the sun is 6 degrees below the horizon. Therefore morning civil twilight begins when the geometric center of the sun is 6 degrees below the horizon, and ends at sunrise. Evening civil twilight begins at sunset, and ends when the geometric center of the sun is 6 degrees below the horizon. Under these conditions absent fog or other restrictions, the brightest stars and planets can be seen, the horizon and terrestrial objects can be discerned, and in many cases, artificial lighting is not needed.

Nautical Twilight:
Begins in the morning, or ends in the evening, when the geometric center of the sun is 12 degrees below the horizon. In general, the term nautical twilight refers to sailors being able to take reliable readings via well known stars because the horizon is still visible, even under moonless conditions. Absent fog or other restrictions, outlines of terrestrial objects may still be discernible, but detailed outdoor activities are likely curtailed without artificial illumination.

Astronomical Twilight:
Begins in the morning, or ends in the evening, when the geometric center of the sun is 18 degrees below the horizon. In astronomical twilight, sky illumination is so faint that most casual observers would regard the sky as fully dark, especially under urban or suburban light pollution. Under astronomical twilight, the horizon is not discernible and moderately faint stars or planets can be observed with the naked eye under a non light polluted sky. But to test the limits of naked eye observations, the sun needs to be more than 18 degrees below the horizon. Point light sources such as stars and planets can be readily studied by astronomers under astronomical twilight. But diffuse light sources such as galaxies, nebula, and globular clusters need to be observed under a totally dark sky, again when the sun is more than 18 degrees below the horizon.