by Nitpicker » Wed Nov 20, 2013 12:23 am
From the filename set on your 4:50 AM photo (the first one), I just checked the time of sunrise at Mount Chokai on 9-Aug-2011. (The time of sunrise is based on the horizon being at the same elevation as the observer. You probably would have been higher than your ENE horizon, so sunrise would have been
slightly earlier from your point of view.)
The definition of sunrise/sunset is as shown here:
On 9-Aug-2011, sunrise was at 4:47 AM and the full disc of the Sun was just apparent above the horizon at 4:50 AM (clouds notwithstanding). These times were about a minute earlier on the previous day.
The presence of anti-crepuscular rays in the photo, implies the presence of crepuscular rays radiating from the Sun, which implies clouds partially obscuring the sunrise, which could explain why you had difficulty in seeing the Sun when you chanced to look behind you. Other explanations could be that you were slightly below and to the west of the peak of Mount Chokai, or that your memory from two and a half years ago is not quite perfect, or that your clock was slightly off, or that you were a bit sleepy for having scaled a mountain before dawn. The time of this photo is said to be 4:50 AM, which if precise, coincided with the full disc of the Sun appearing just above the horizon. But (at least part of) the Sun would likely still have been "below" the peak of Mount Chokai, meaning that (at least some of) the crepuscular rays hitting the peak were inclined upwards, such that the shadow of the peak was cast onto the anti-twilight arch of the sky, rather than the Sea of Japan.
From the filename set on your 4:50 AM photo (the first one), I just checked the time of sunrise at Mount Chokai on 9-Aug-2011. (The time of sunrise is based on the horizon being at the same elevation as the observer. You probably would have been higher than your ENE horizon, so sunrise would have been [i]slightly [/i]earlier from your point of view.)
The definition of sunrise/sunset is as shown here:
[img2]http://upload.wikimedia.org/wikipedia/commons/thumb/9/93/Sunrise-Sunset_angle.svg/640px-Sunrise-Sunset_angle.svg.png[/img2]
On 9-Aug-2011, sunrise was at 4:47 AM and the full disc of the Sun was just apparent above the horizon at 4:50 AM (clouds notwithstanding). These times were about a minute earlier on the previous day.
The presence of anti-crepuscular rays in the photo, implies the presence of crepuscular rays radiating from the Sun, which implies clouds partially obscuring the sunrise, which could explain why you had difficulty in seeing the Sun when you chanced to look behind you. Other explanations could be that you were slightly below and to the west of the peak of Mount Chokai, or that your memory from two and a half years ago is not quite perfect, or that your clock was slightly off, or that you were a bit sleepy for having scaled a mountain before dawn. The time of this photo is said to be 4:50 AM, which if precise, coincided with the full disc of the Sun appearing just above the horizon. But (at least part of) the Sun would likely still have been "below" the peak of Mount Chokai, meaning that (at least some of) the crepuscular rays hitting the peak were inclined upwards, such that the shadow of the peak was cast onto the anti-twilight arch of the sky, rather than the Sea of Japan.