“So remarkable that the Chinese copied it!”
Cable puts a gash in Puerto Rico’s Arecibo telescope which is facing tough financial times
The road to the Arecibo Observatory in northwestern Puerto Rico winds upward through farms and rainforest. Chickens run across the road. Then, suddenly, you reach the top: a fence, guards and gleaming white buildings and towers, as if you had stumbled into the lair of a James
Bond supervillain.
Hanging in the sky like a skeletal flying saucer, suspended by cables from three mountaintop towers, is a giant triangular structure of girders. Five hundred vertiginous feet below, nestled in a sinkhole valley, is an aluminum dish 1,000 feet wide — an antenna to catch radio waves from the cosmos or to beam them out.
In early August, hearts sank throughout the universe when news surfaced that a falling cable had ripped a 100- foot- long gash in that antenna, temporarily putting it out of commission. For more than half a century, the Arecibo telescope has been one of the great icons of interstellar longing.
Built in 1963, it served as the flagship for the search for extraterrestrial intelligence, or SETI, the optimis
tic quest for radio signals from alien civilizations. In 1974, astronomers sent their own message out into the void, toward a cluster of stars known as Messier 13. ( Travel time is 25,000 years, so we should not expect a reply for at least 50,000 years.)
Astronomers used the observatory to map dangerous asteroids as they buzzed past Earth, and to measure the rotation rate of Mercury. Employing the antenna’s exquisite sensitivity, they tuned in to the enigmatic clockwork blips of distant pulsars, discerning in their changing rhythms secrets of unworldly physics. For
years the National Astronomy and Ionosphere Center, as the observatory is officially known, hosted the largest single radio antenna on the planet, only surpassed in 2016 by a new telescope in China that is 1,600 feet in diameter.
“It is a remarkable scientific instrument, so emblematic of our self- confident years in science,” Michael Turner, a cosmologist now at the Kavli Foundation and former assistant director of the National Science Foundation, said in an email. “So remarkable that the Chinese copied it!”
On the morning of Aug. 10, a cable that helped support the triangular structure that holds the antenna’s radio receivers snapped and crashed through the antenna. About 250 of the 38,778 aluminum panels that make up the dish were damaged. No one was hurt.
Arecibo’s director, Francisco Córdova of the University of Central Florida, and Ramon Lugo, director of the university’s Florida Space Institute and principal investigator for the observatory, reported in a Zoom news conference a few days later that nobody knew yet why the cable, which was more than 3 inches thick, had snapped. It had been installed in the 1990s to bolster a support for a new addition to the 900- ton instrument platform and was expected to last another 15 to 20 years, Córdova said.
Nor did the two researchers know how long it would take to repair the damage, or how much it would cost. Fabricating and shipping a new cable could take months, Lugo said.
The loss of a few hundred panels was no big deal, Córdova said. The bigger issue is making sure the instrument platform is structurally stable. “We’ve been tested before,” Córdova said, alluding to a long history of mishaps and crises, including earthquakes, Hurricane Maria in 2017 and now the COVID- 19 pandemic. “This is just another bump in the road.”
The Arecibo facility was originally built and run by Cornell University under contract to the Air Force Research Laboratory, partly out of a desire to understand the properties of objects like nuclear warheads tumbling through the upper atmosphere. As a result, it was built to be both a telescope and a planetary radar.
One of its directors over the years was astronomer Frank Drake. He was famous for first pointing a radio telescope at another star for indications of friendly aliens, then for an equation, still in use today, that tries to predict how many of “them” are out there.
On Nov. 16, 1974, Drake beamed the equivalent of a 20trillion- watt message toward M13, a cloud of about 300,000 stars some 25,000 light- years from Earth, as part of a celebration of an upgrade to the antenna.
The message consisted of 1,679 zeros and ones. Arranged in 73 rows and 23 columns, the bits formed pictures of a stick man, the radio telescope, a DNA helix, the solar system, the numbers 1 through 10 and more. Before Drake sent it off, he tried out the message on his Cornell colleagues, including Carl Sagan. None of them could decode all of it.
But the future of Arecibo has become precarious. In 2007, the National Science Foundation, which has run the observatory since the early 1970s on an increasingly tight budget, said the observatory might have to close if a partner could not be found to take on some of the financial load.
Since 2016, it has been managed by the University of Central Florida under a cooperative agreement with Universidad
Ana G. Méndez and Yang Enterprises. The annual budget is about $ 12 million, including funds from NASA and the National Science Foundation, according to the University of Central Florida.
Still, the beat goes on. Only days after the accident, the University of Central Florida sent out a news release describing work by a team led by Jian Li, an astronomer at the Deutsches Elektronen- Synchrotron in Zeuthen, Germany, using the Arecibo telescope and other instruments. The team discovered what they called a “heartbeat” of gamma rays emanating from a gas cloud in the constellation Aquilla. The gamma rays — a very high- energy form of light — were being produced in rhythm with the outbursts from a wobbly and enigmatic black hole called SS 433, which is 100 light- years away from the cloud. It’s unclear how this black hole could cast its influence across so vast a distance.