Daniel, some time ago, 55-60 yrs, give or take, I was taking a bonehead algebra class (our high school at that time totaled 22 students, and no higher math was taught). The professor asked for an answer to a particular homework question, and I thought I had the right answer, so I raised my hand. When asked, I gave my answer. He frowned, maybe even scowled, and asked "Holmes, how did you arrive at that answer?" Well, if you know me, I am kinda a smart ass, so I replied "I applied the sidereal equation." (grew up in a very dark, rural area, and was always interested in the night sky, so my first term in college I took an astronomy class. We had a small domed observatory & I cannot even remember anything about the telescope, but do remember being excited to see Venus? in the daylight. I had never thought about reflected sunlight in the daytime. I still have the textbook from 1951. It is kinda fun to pull out now & then to read it. So, long about ways to tell how I knew the term sidereal). So, anyway, the prof looked puzzled and asked just what the heck the sidereal equation was. I deadpanned replied, "plus or minus enough to get the right answer." The class & I seemed to be the only ones in the room enjoying that response. Needless to say, it was then all uphill for me the rest of the year! 73, lh On 9/14/2011 2:25 PM, daniel turner wrote:

I just lifted this picture from spaceweather.com. It shows a whimsical picture of a type often seen around the harvest moon.

http://www.slas.us/gallery2/main.php?g2_itemId=4683

Its fun to shoot pictures like this but I like to figure out how far the camera was from the subject. It's easy but involves a little math.

The wheelbarrow bed is about 40 inches long and the moon looks to be about 3/4th of that wide. We know that the moon is about a half degree wide. half a degree time pi and divided by 180 gives .0087 radians. One over radians gives 144. That times the 30 inches the moon appears to be wide give 3437.7 inches. Divided by 12 gives 286 feet. thats the rough distance between the camera and the wheelbarrow.

Some times the subject is much farther away, like a climber on the side of a mountain or a car on a hillside. but the point is that the picture contains the information you need to find where the camera was at the time of the photo.

DT _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.slas.us/gallery2/main.php

Patrick said one time that sometime somebody might place the moon on top of the pole (at pit and pole) but I was actually thinking of picking up that old broken tv laying in the pit and put the moon in it, would have been cool IMO.. -Jorge G.