Chilean mediators today launched a new effort to resolve a 12-day-old strike by workers at the Atacama Large Millimeter/submillimeter Array (ALMA), the world’s largest radio telescope. The dispute has forced the facility to put most of its observations on hold as the management attempts to negotiate with ALMA’s 195-member union of administrative workers, technicians, and support staff members.

Built at an altitude of 5200 meters above sea level, on the Chajnantor plateau in northern Chile, ALMA is a collaboration between the United States, Japan, Europe, and Chile. It is managed by Associated Universities Inc., a Washington, D.C.-based organization. The observatory, which operates an array of 66 antennas, was officially inaugurated in March, although it began producing science more than a year ago. Astronomers are using the facility to study a host of questions, including how the first stars and galaxies formed and the birth of planets.

ALMA has an international staff of astronomers and a local staff of administrative employees, technicians, and other workers who support the observatory’s operations.

Last month, the union began negotiating a new 3-year contract with the management, but talks broke down when the union demanded a 15% salary raise and bonuses for children of the workers. The union called a strike on 22 August. Two rounds of negotiations have failed to resolve the dispute. A fresh attempt began earlier today, mediated by an agency of the Chilean government, an ALMA source tells ScienceInsider.