My most unusual lunar eclipse photo
This is a combination of two photos taken 15 seconds apart during the waning partial phases of the total lunar eclipse on Wednesday morning. The camera is tilted into equatorial co-ordinates since it was piggy-backed on a telescope, so the horizon is at the lower-right. You can see stars in the upper-left. The most obvious thing beyond the tilt is that there are clouds in the way...
But what makes this photo unusual and maybe even a little mind-blowing is the intense red glow in the clouds. At first, you might think that this red glow is coming from the Moon, because it is reminiscent of the red colour at the centre of a totally eclipsed Moon. And you'd be on the right track, because it most certainly is the same colour as the centre of the umbra. But that glow isn't coming from the Moon. At this point, the Moon was still 6 minutes away from totality. The Moon was still only partially eclipsed, so the predominate colour of the light coming from it was still white, not red. And besides, those clouds were too thick for the Moon to shine through, except in the small gaps between the clouds right near the Moon - and the light shining through those gaps is indeed predominately white, as you can see from the photo. So that red glow is actually shining on the underside of the clouds. This photo was taken deep in farming country, so that was not light pollution, not that light pollution would ever be that deeply red.
That red glow was actually coming from distant sunrises hundreds of kilometres back behind the camera. It is an early contribution to twilight during a phase called astronomical twilight. It is intensely red because the light from the Sun is being filtered and refracted through the entire depth of the Earth's atmosphere almost two full times before being intercepted by the underside of those moderately high clouds. But this means that this red glow IS THE VERY SAME red light that would illuminate the central portion of the shadow cast on the Moon during a lunar eclipse! That is, except in this case, because my local contribution to that red glow was being mostly blocked out by the clouds you see in the picture.
In other words... you may know that, viewed from the Moon, the Earth would look like a red ring during the deepest part of a total lunar eclipse. Well, the band of redness in the photo is part of that red ring, but blocked by clouds at this particular location.
But what makes this photo unusual and maybe even a little mind-blowing is the intense red glow in the clouds. At first, you might think that this red glow is coming from the Moon, because it is reminiscent of the red colour at the centre of a totally eclipsed Moon. And you'd be on the right track, because it most certainly is the same colour as the centre of the umbra. But that glow isn't coming from the Moon. At this point, the Moon was still 6 minutes away from totality. The Moon was still only partially eclipsed, so the predominate colour of the light coming from it was still white, not red. And besides, those clouds were too thick for the Moon to shine through, except in the small gaps between the clouds right near the Moon - and the light shining through those gaps is indeed predominately white, as you can see from the photo. So that red glow is actually shining on the underside of the clouds. This photo was taken deep in farming country, so that was not light pollution, not that light pollution would ever be that deeply red.
That red glow was actually coming from distant sunrises hundreds of kilometres back behind the camera. It is an early contribution to twilight during a phase called astronomical twilight. It is intensely red because the light from the Sun is being filtered and refracted through the entire depth of the Earth's atmosphere almost two full times before being intercepted by the underside of those moderately high clouds. But this means that this red glow IS THE VERY SAME red light that would illuminate the central portion of the shadow cast on the Moon during a lunar eclipse! That is, except in this case, because my local contribution to that red glow was being mostly blocked out by the clouds you see in the picture.
In other words... you may know that, viewed from the Moon, the Earth would look like a red ring during the deepest part of a total lunar eclipse. Well, the band of redness in the photo is part of that red ring, but blocked by clouds at this particular location.