Sears Tower string project--part two

After measuring the 1450 feet distance with this measuring wheel, it was suprising how far it was. (for explanation of this project, see this previous post). The distance was far enough away that it seemed odd to be taking photos of the Sears Tower. People were looking at me curiously with the measuring wheel at the end distance... To read the rest of this post, click on the comments.

It would be nice to use some sort of other marker. I wasn't very pleased with the photographs. Here and here. The angle doesn't work well in photos with chalk. Maybe an orange cone. Actually I should have asked some of the people walking by to stand in the shot. It would be cool if I could get a people holding hands to form a line from the base of the Tower to 1450 foot mark.

It would be even more incredible to have people holding hands to form a circle with a radius of 1450 feet around the Sears Tower. Can you imagine that around the World Trade Center site? Wow.

How many people would it take to form the straight Sears Tower line of 1450 feet? Saying that each person would take up an average of three feet. That would be 483 people. The circumference is 9111 feet. (Oh weird. Can you imagine if the World Trade Center height was 1450? That 9111 feet number would be very odd. But the WTC was 1350 feet tall--8482' circumference). So it would take about 3,037 people to circle the Sears Tower. But then you have buildings in the way. It would be neat to form the illusion of a perfect circle. When the circle runs into a building, the end person just "holds hands" with the building.

This circle of people would have to be either
A) photographed from the sears tower
B) photographed from an airplane/helicopter
You couldn't get the sense of a circle from the ground.
All the people could wear white tshirts, so you could more easily identify the people standing from far above. And the tshirts could be their reward for participating.

But back to the simple photo idea with one person at 1450' distance with the Sears tower in the background. Maybe this person could hold a sign and stand at the 500' mark, then 1000', etc. And the sign would indicate the distance--perhaps a thermometer style image. The further away from the tower. The more the thermometer fills up. Maybe the thermometer is a diagram of the Sears Tower.

Do cell phones work at the top of the Sears Tower? Can you see someone 1450 feet away on the ground when in the observation deck? How big would the a sign have to be to be legible?