Friday, December 12, 2008

Full Moon

The moon has been very bright lately, rivaling a nearby streetlight even when not full. (I could read the labels on our recycling bin by moonlight last week.) I learned one of the reasons today: Tonight's brilliant full moon coincides with the moon's closest approach to the earth in its elliptical orbit around the earth, making it 14% bigger and 30% brighter than usual.

It was definitely time to get out the camera.

Click image for larger view. Details below the fold.

Photo taken with a Nikon D70 using a 70-300 lens at full zoom (300 mm), shot at f5.6 at 1/2000 of a second exposure with sensitivity set to 800 ISO. Only edit was to crop to 500x500 and convert to greyscale, although I did not see any color artifacts (probably because the sensors were not being pushed anywhere near their limit at that exposure).

I can't get over the detail for a photo with a fairly modest lens, particularly the mountains visible along the upper right edge. It took a lot of experiments with the camera set to shutter priority to figure out what appeared to give the best image. The ones shot at 1/8000 didn't have enough brightness in the ejecta, while slower ones brought out the halo (the sky is actually fairly hazy with humidity) while losing all of the detail on the surface.

OK, enough of a diversion. Time to get back to grading exams.

1 comment:

Matt Springer said...

That's really neat. I was driving last night and saw it rise. The illusion of a very large moon on the horizon was incredible - now I know that it in fact was a little bigger than normal regardless.