The Arecibo Radio Telescope, at Arecibo, Puerto Rico. At 1,000 feet (305 m) across, it is the largest dish antenna in the world. The dish, built into a bowl in the landscape, focuses radio waves from the sky on the feed antenna suspended above it on cables. Since the dish itself cannot move, the telescope is steered to point at different regions of the sky by moving the feed antenna (dome) along the curving metal track. Photo: Wikimedia
ARECIBO, Puerto Rico -- On January 13, 2014, the William E. Gordon radio telescope in Arecibo, Puerto Rico sustained damage following a 6.4 magnitude earthquake that was centered 37 miles northwest of Arecibo. Following the earthquake, Arecibo Observatory staff conducted a structural survey that revealed serious damage to a main suspension cable section, with apparent breach of several cable strands within that cable, which supports the 900-ton focal platform of the telescope. There are 18 main suspension cables in all.
A short cable segment and splice near the top of one of the telescope towers, which is more rigid than the rest of the suspension system, suffered damage when the earthquake shook Arecibo. Ammann and Whitney Consulting Engineers were brought in to assess the damage and to consider repairs needed before the telescope could return to full operations.
"In an abundance of caution, telescope motion had been very limited since the earthquake," said Robert Kerr, PhD, the Observatory's director and a principal scientist at SRI International, which leads a multi-organization team that manages, operates, and maintains the Arecibo Observatory. "Nevertheless, the telescope continued its science mission, including participation in a 10-day global ionospheric study in late January and continuing a productive search for pulsars in the sky above Arecibo."
Arecibo Observatory has now completed the immediate repair of the William E. Gordon telescope. The repair design was created by Ammann and Whitney and the structural repair work was performed by Arecibo Observatory staff. Beginning on March 13, the telescope is back to full service for the scientific community.
The Arecibo Observatory is operated by SRI International, teaming with The Universidad Metropolitana and the Universities Space Research Association, in a cooperative agreement with the National Science Foundation.