Amazing Science Images You Must See
Blowing Smoke Rings at the Edge of Space
These strange circular clouds are no natural phenomenon. They were created by NASA in order to study the circulation in the atmosphere over North America.
On March 27, NASA successfully launched five suborbital rockets in order to study the upper level jet stream. Each rocket, launched one after another 80 seconds apart, released a chemical tracer to create these milky clouds at the very edge of space, 65 miles (105 km) up.