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Sandia National Laboratories’ four-channel, silicon photonic single-sideband modulator chip, measuring 8 millimeters on each side and marked with a green Sandia thunderbird logo, sits inside packaging that incorporates optical fibers, wire bonds, and ceramic pins. Credit: Craig Fritz, Sandia National Laboratories ==================================================================== A milestone in quantum sensing is drawing closer, promising exquisitely accurate, GPS-free navigation. Peel apart a smartphone, fitness tracker or virtual reality headset, and inside you’ll find a tiny motion sensor tracking its position and movement. Bigger, more expensive versions of the same technology, about the size of a grapefruit and a thousand times more accurate, help navigate...

The U.S. Air Force on May 27 successfully launched the first of a new generation of GPS satellites aboard a Delta 4 rocket from Cape Canaveral Air Force Station, Fla., the service announced May 28. The GPS 2F-1 satellite was placed into a roughly 17,600-kilometer orbit and joins an operational constellation of 30 previous-generation GPS satellites, the Air Force press release said. The GPS 2F satellites are more powerful than previous GPS satellites, generating more robust, jam-resistant signals, according to prime contractor Boeing Space and Intelligence Systems of Seal Beach, Calif. The satellites will also provide a third civil signal...