The Atacama Large Millimeter/submillimeter Array (ALMA) is composed of 80 high-precision antennas located on the Chajnantor plain of the Chilean Andes, 5000 meters above sea level. Using ALMA, astronomers have unprecedented visibility into deep space. The antennas are up to several kilometers away from the control center, so the receivers must be synchronized to within femtoseconds lest the images be blurred.

Their solution is a General Photonics long range polarization-stabilized fiber stretcher assembly that combines several of General Photonics’ patented technologies. This custom module enabled phase compensation of variations due to thermal effects and even earthquakes.