Costly Ball to Guide Astronauts (Nov, 1961)
I wonder if this was part of the inspiration for Gravity Probe B, a satellite designed to measure how spacetime is warped by the earth. It had some seriously spherical gyroscopes:
“At the time, the gyroscopes were the most nearly spherical objects ever made. Approximately the size of ping pong balls, they are perfectly round to within forty atoms (less than 10 nm). If one of these spheres were scaled to the size of the earth, the tallest mountains and deepest ocean trench would measure only 2.4 m (8 ft) high”
Costly Ball to Guide Astronauts
A LITTLE metal ball, worth more than 30 times its weight in gold, is being tediously fashioned into shape as part of a guidance system that may help future astronauts find their way around the universe.
General Electric Co., Schenectady, N. Y., says the sphere of niobium will be a critical part of an inertial guidance system giving pinpoint accuracy to navigation of a jet, ocean liner, space ship, or submarine—largely as a result of suspending it in a vacuum and rotating it as the heart of a super-precise gyroscope. When niobium is super-cooled to near absolute zero (about minus 460°F), it becomes superconductive and will be suspended in a magnetic field.
The gray, rather soft metal costs about $80 a pound; the painstaking work of shaping it has made it almost invaluable. G. E. says the work has been so delicate that the warmth of a human body drawing near has been enough to cause measurable distortion.
Caption: An instrument maker holds a small sphere of niobium which, minus the lips at top and bottom, is being superfinished to a tolerance of 10 millionths of an inch. In the background is a picture of a spiral nebula.