The darkest hour is just before the dawn... No it isn't!

 

From timeanddate.com/sun/uk/newcastle-upon-tyne

"The darkest hour is just before the dawn" may be psychologically true as a proverb - but is astronomically false. 

If dawn is defined as the sunrise; the night goes through three evolving phases of increasing light (defined by the sun's angle below the horizon), that are conventionally separated as such:

Astronomical dawn - Sun is 0-6 degrees below the horizon: when the sky lightens from black towards blue such that fainter stars disappear.

Nautical dawn - Sun is 6-12 degrees below the horizon: when, on a clear day, the horizon and brighter stars are still visible at sea.

Civil dawn - Sun is 12-18 degrees below the horizon: when all the stars (except, maybe, Venus) disappear, and it is light enough over land to do normal outdoor stuff.  

The truth is that it is darkest in the middle of the night, when the sun is at its greatest angle below the horizon. 

That doesn't fit the moral of the proverb - which is rooted in an archetypal narrative of eucatastrophe. 

Yet I can't help but suppose that "the darkest hour is just before the dawn" is a proverbial product of the kind of people who never look at the sky, or who have not been out of bed early enough to observe the dawn for themselves!...