We now live in a Silicon Age; Solid-state electronics has replaced vacuum tubes in radios, computers and other electronic and radio frequency gadgetry.  Still vacuum electronic devices, have not become extinct, the magnetron that made radar possible in the first half of the 20th century is still employed in microwave …

The first flight of Moscow’s new Tupolev PAK-DA stealth bomber has been delayed by about three years. However, according to Russian Deputy Defense Minister Yuri Borisov,” The work on the development of the PAK DA strategic bomber (prospective aviation complex for long-range aviation) continues and it will not be stopped.”. …

The ACES program aims to develop portable, battery‐powered atomic clocks with stability, repeatability, and environmental sensitivity approaching that of laboratory‐grade cesium beam frequency standards. “The history of human knowledge is reflected in our clock technology,” says Robert Lutwak, program manager for the agency’s Atomic Clocks with Enhanced Stability (ACES) project. …