Cable failures endanger renowned Puerto Rico radio telescope

SAN JUAN, Puerto Rico (AP) — Giant, aging cables that support one of the world's largest single-dish radio telescopes are slowly unraveling in this U.S. territory, pushing an observatory renowned for its key role in astronomical discoveries to the brink of collapse.

The Arecibo Observatory, which is tethered above a sinkhole in Puerto Rico’s lush mountain region, boasts a 1,000-foot-wide (305-meter-wide) dish featured in the Jodie Foster film “Contact” and the James Bond movie “GoldenEye.” The dish and a dome suspended above it have been used to track asteroids headed to Earth, conduct research that led to a Nobel Prize and helped scientists trying to determine if a planet is habitable.

“As someone who depends on Arecibo for my science, I’m frightened. It’s a very worrisome situation right now. There’s a possibility of cascading, catastrophic failure,” said astronomer Scott Ransom with the North American Nanohertz Observatory for Gravitational Waves, a collaboration of scientists in the U.S. and Canada.

Last week, one of the telescope’s main steel cables that was capable of sustaining 1,200 pounds (544 kilograms) snapped under only 624 pounds (283 kilograms). That failure further mangled the reflector dish after an auxiliary cable broke in August, tearing a 100-foot hole and damaging the dome above it.

Officials said they were surprised because they had evaluated the structure in August and believed it could handle the shift in weight based on previous inspections.

It’s a blow for the telescope that more than 250 scientists around the world were using. The facility is also one of Puerto Rico’s main tourist attractions, drawing some 90,000 visitors a year. Research has been suspended since August, including a project aiding scientists in their search for nearby galaxies.

The telescope was...