Shadows are a natural consequence of opaque walls in an illuminated Universe. Light shines; photons travel until they hit an object through which they cannot pass; this blockage creates a shadow ...

Textron is flight testing a new Block 3 version of its AAI-developed RQ-7 Shadow UAS, which the U.S. Army has been using for 20 years and, according to Textron, plans to use for at least 10 more.