Hams and astronomy enthusiasts the world over are familiar with the massive Arecibo radio telescope, the primary instrument of the Arecibo Observatory in Puerto Rico. Even the uninitiated in those worlds have probably seen it make an appearance in movies like “Contact” and “GoldenEye” (a personal favorite of mine).
The latter almost felt like a premonition now that the 900-ton instrument platform hanging above the telescope’s 1,000-foot dish fell almost 400 feet on December 1, 2020. While the telescope was set to be decommissioned anyway, the failure of the cables that suspended the platform raised questions—questions we now have answers to.
How in the Galaxy Could It Have Collapsed?
In a recently released report, a joint investigation into the matter revealed that a variety of factors led to the eventual collapse. Conducted by the University of Central Florida and the National Science Foundation (NSF), the report showed that zinc creep in the telescope’s cable sockets and Hurricane Maria played large roles.
Zinc creep is the time-dependent strain that takes place under a given load.
“The root cause of the Arecibo Telescope’s collapse was unprecedented and accelerated long-term zinc creep induced failure of the telescope’s cable spelter sockets,” according to the report, which was released in October, 2024.
The catalyst for this acceleration traces all the way back to Hurricane Maria in 2017, which was then a category four storm.
Typically, a hurricane should have had little to no effect on the cables. However, the NSF claimed that the cables were in a worse state than previously known due to a failure in inspections and reporting leading up to Maria.
Another factor that may have contributed was the unique environment the cables were in. Since they were used to suspend equipment in a “powerful radio telescope environment,” electric currents could have accelerated zinc creep. It’s important to note, however, that there isn’t enough data to support this hypothesis even though “no other mechanism has been found likely,” according to the report.
Despite this, the investigation concluded that—even without Maria—the observatory would have eventually collapsed due to the unique, accelerated zinc creep.
One Small Step for Hams, One Giant Leap for Hamkind
The importance of the Arecibo Observatory in the field of astronomy and amateur radio cannot be understated.
Famous astrophysicist and amateur radio innovator Joe Taylor, K1JT, with the help of Russell Hulse, used the telescope to seek out new pulsars in the galaxy in 1970. This work led to the 1974 discovery of a binary pulsar, comprised of two neutron stars that orbit around each other. The discovery provided proof of gravitational radiation, which was part of Albert Einstein’s Theory of Relativity.
Their work earned them the Nobel Prize in Physics in 1993.
Also in 1974, the observatory’s telescope beamed the first radio signal into space with the goal of contacting alien life. The three-minute transmission, sent as binary numbers, was sent to a star cluster at the edge of the Milky Way— 21,000 light-years away from Earth.
The transmission, called the “Arecibo Message,” was comprised of information about Earth’s location, DNA structures, and an image of a human being among other things.
A myriad of other discoveries were made using the observatory including the detection of an ionized helium layer in the Earth’s ionosphere, the first-ever exoplanet, and the detection of methanimine and hydrogen cyanide—key ingredients in forming amino acids—in a galaxy 250 million light-years away, according to the NSF.
Aside from discovering the binary pulsar using radio waves, Taylor also used the observatory to bounce radio signals off the moon in 2010. Using the observatory gave the signal so much power, hams using equipment like a five-element Yagi antenna and a radio with a 70cm SSB receive capability could listen, according to the ARRL.
Observations and Future Plans of a Beloved Scientific Icon
Days after the collapse, DX Engineering’s CEO Tim Duffy, K3LR, spoke with Angel Vasquez, WP3R, the head of telescope operations at the time about the incident and his memories of working there.
Vasquez, who was in the observatory’s control room when the support cables snapped, told Duffy that he was lucky to have worked there and that he would have great things to tell his grandkids. You can watch the interview here.
While the observatory is no longer operational, there have been talks about bringing it back in some form, though not at the same scale. The latest proposal showed plans to install around 102 13M satellite dishes that would have a collecting area equivalent to a single 130M dish. However, for the time being those plans seem to be on hold.
In the meantime, the NSF recently announced plans to open the Arecibo Center for Culturally Relevant and Inclusive Science Education, Computational Skills, and Community Engagement (NSF Arecibo C3 to avoid the word salad).
Launching as a pilot in the summer of 2024, the center welcomed students and educators to learn about molecular biology using hands-on skills. Other subjects that are expected to be covered in the future include astronomy and data science among other STEM topics.
Arecibo C3 is expected to feature a research lab and an interactive science center. Programs will include exhibitions, science talks, films and more for children, families and the public, according to a news release from the NSF.
A standout feature of the new center? An exhibition about the Arecibo Observatory, its legacy, and the contributions it made to both the scientific and the amateur radio community at large.
