End of an era: Requiem for a telescope; The Arecibo Observatory

NEW YORK: When the giant Arecibo Observatory in Puerto Rico collapsed in December 2020, it punched a hole in astronomy. For half a century Arecibo was the mightiest telescope on the planet. One thousand feet wide, it listened to radio signals from the stars — as well as from pulsars, planets, asteroids and more — for any hints of intelligent life, potentially Earth-killing objects and insights into the mysteries of gravity and space-time.

The demise of Arecibo also punched a hole in the pride and the economy of Puerto Rico, which has repeatedly been hit by hurricanes, earthquakes and widespread electrical outages. Since 1963, when the telescope was founded, generations of schoolchildren in the territory have trooped through the hills to a sci-fi setting: a gigantic, concave antenna, set like a mixing bowl in a mountain valley, with 900 tons of radio receivers suspended above it. There, young students could rub elbows with renowned scientists at work and be inspired by science, particularly astronomy. Many grew up to be astronomers themselves.

Those trips will continue, sort of. Last week the National Science Foundation, which owns the Arecibo Observatory, said it would spend $5 million to establish a world-class educational center at the site. The Arecibo Center for STEM Education and Research would include the Ángel Ramos Science and Visitor Center, as well as an exhibition space, a laboratory, an office space, dormitories, an auditorium and a cafeteria.

The only thing missing will be the telescope. The plan “does not include rebuilding the 305-meter telescope or operational support for current scientific infrastructure, such as the 12-meter radio telescope or Lidar facility,” the National Science Foundation said last week in a statement soliciting proposals from researchers hoping to conduct projects at the site. Dan Werthimer, an astronomer at the University of California, Berkeley, who had used the telescope throughout his career to search for radio signals from extraterrestrial civilisations, lamented the decision to not rebuild. “Arecibo was my favorite telescope in the universe,” he said. “This is a sad time for the people of Puerto Rico,” Werthimer added. “The Arecibo telescope was their pride and joy.” The sense of loss rippled through the astronomical community. “It was then a great surprise last Thursday when the N.S.F. announced that it planned to turn the facility into a mainly STEM education side and curtail almost all of the science,” Joanna Rankin, a radio astronomer from the University of Vermont and part of a group of some 400 astronomers known as the Arecibo Science Advocacy Partnership, wrote in an email. “Many of us who have used the instrument and know its many virtues have been quite disconcerted by this unexpected turn of events.” A headline in The Register, a daily online journal covering technology, complained that the National Science Foundation planned to replace the telescope with a school.

The Arecibo Observatory, officially named the National Astronomy and Ionosphere Center, was originally built as an interplanetary radar as well as a radio telescope to study, among other things, the properties of objects such as warheads tumbling through the atmosphere. Over the years it stood as a symbol of human curiosity and cosmic optimism. It appeared in the film “Contact,” which features Jodie Foster as an astronomer who discovers a communication signal from outer space, and in “Goldeneye,” as the lair of a James Bond supervillain.