a Taj MuttHall Dog Diary: Baying at the Moon

Tuesday, August 28, 2007

Baying at the Moon

SUMMARY: Why I dragged myself out of bed from 2 a.m. until 4 a.m. this morning

Mr. Moon in all his fullness.
Oh, no, a giant sky monster is taking a bite from ripe old Mr. Moon!
What it looks like exposed for the part that's now in Earth's shadow.
When I started doing long exposures like this, where part of the moon was still fully lit by Mr. Sun, I got this odd light-echo effect. I have no idea what causes it. Some artifact of the way the camera processes images or of the long lens? Anyone out there know?
About halfway through, 9 minutes after the previous photos. Once the shadow starts moving in, it moves pretty quickly.
Same time, exposed for the shadowed side.
About 3/4 of the way into the penumbra, another 9 minutes later.
Same time, exposed for Mr. Shadow. (Yes, I use respectful address for all large celestial bodies and their bodily functions.)
Almost there, and now the shadowed part is glowing sanguine to the naked eye. Before this, the reflected sun has overwhelmed the slight glow of the darker parts, so that we've seen only a diminishing white orb with our own eyes. Only longer exposures on the camera have revealed the dark parts.
Totality. It'll stay pretty much like this for the next hour or so. The challenge is that the moon is all so dark, now, that I have to take even longer exposures, and I don't have a clock drive for my camera, so it's just going to be blurry. This is about 6 seconds and looks fairly close to what humans could actually see.
To give you an idea--I wanted this exposure's lightness, but at 20 seconds the blur was too much. Mr. Moon really travels! You can see how far everything traveled in 20 seconds by the star tracks in the upper left.


  1. See, I knew there was a good reason not to drag my butt out of bed at some unspeakable hour. Surely someone would come along and take groovy pictures that I could at a far more civilized hour. Of course those could be pictures of oranges for all I know but they're pretty cool looking one way or the other.

  2. Dang, you guessed my evil secret! How'd you know I have excess oranges on my tree AND spare felt-tip markers?

    Ahhhh, the view would've been crummy from Colorado anyway. ;-)


  3. Very cool. I really like how you exposed for the light and shadowed parts. I was up around 2:30am PDT so I saw the partially covered Mr Moon. Not being nearly as dedicated as you are, I went back to bed.

    Do you have a telescope that you can attach a camera to? (Not that you need it in this case.) I have a telescope (but no camera attachment yet) that you can borrow to continue your slide down this slippery slope of geekdom.


  4. Wow! Thanks for posting those great pictures (and getting up at 4:00 :-)