Apollo 8 placed the mission on course for the Moon, the command and service modules (CSM), the remaining Apollo 8 spacecraft, separated from it. The crew then rotated the spacecraft to take photographs of the spent stage and then practiced flying in formation with it. As the crew rotated the spacecraft, they had their first views of the Earth as they moved away from it – this marked the first time humans had viewed the whole Earth at once. Borman became worried that the S-IVB was staying too close to the CSM and suggested to Mission Control that the crew perform a
Silly Putty lint, pet hair, or ink from various surfaces. The material's unique properties have found niche use in medical and scientific applications. Physical therapists use it for rehabilitative therapy of hand injuries. A number of other brands (such as "Power Putty" and "TheraPutty") alter the material's properties, offering different levels of resistance. The material is also used as a tool to help reduce stress, and exists in various viscosities based on the user's preference. Because of its adhesive characteristics, it was used by Apollo astronauts to secure their tools in zero-gravity. Scale model building hobbyists use the putty as a masking