another big lost in 2020

The 305-meter radio telescope at the Arecibo Observatory in Puerto Rico has survived decades of hurricanes, including Hurricane Maria in 2017, and earthquakes, including unusually strong earthquakes in early January 2020. It has also survived attempts by its owner, the US National Science Foundation, to cut funding. But in the early morning hours of December 1, 2020, its 900-ton suspended instrumentation platform collapsed, destroying the 57-year-old telescope.

Arecibo has contributed to many important discoveries, including observations of pulsars that won a Nobel Prize and the first confirmed exoplanets. Closer to home, the observatory’s radar equipment emitted radio signals to identify the shape, rotation and speed of potentially dangerous asteroids for NASA. The telescope has also monitored dwarf stars, planets in our solar system, and disturbances in Earth’s atmosphere.

The collapse of Arecibo was a heavy blow in what was already a year of loss. The pandemic has forced my interactions with students and colleagues online, and I worry about the health of my family: my parents in their 80s as well as my wife, a healthcare worker who has lost a friend and colleague to COVID. -19. In times like these, it can be heartwarming to remember the beginnings.

I was 12 when I first visited the Arecibo observatory. In 1981, tours were by appointment and I called from a pay phone to try to make a reservation. Garred “Gerry” Giles, the observatory’s chief science officer, answered the phone in broken Spanish and assigned me a day and an hour. My parents agreed to make the two hour drive. We all knew about my enthusiasm for astronomy, but I don’t think anyone predicted that I would grow up to be a physicist and astrobiologist at the University of Puerto Rico at Arecibo.

Gerry showed us the Observatory’s control room, where a large window overlooked the massive suspended platform, a rotating structure that contained the receivers into which the radio signals reflected from the antenna below focused. That year, measurements from the observatory were used to create the first radar maps of the surface of Venus: the planet’s thick clouds had hampered optical observations, but Arecibo’s powerful radio signals could pass. and bounce back. I still have the printed images of Venus that Gerry gave me that day.

My parents and I went under the dish in a Jeep on a dirt road. From a distance the dish looked like a solid shell, but it was made up of many lattice-shaped plates through which the light reached the ground below. The area was damp, calm and lush with vegetation. The dish was high above us, and the suspended platform visible even higher, through the mesh.

Decades later, I presented my first scientific lecture at the observatory as a visiting scientist. My research focuses on the habitability of planets, on understanding the conditions necessary for all life, from the microbial to the intelligent. A week before I arrived, I searched for Gerry in an old phone book, unsure if he was still in Puerto Rico. I told him that over 25 years ago he gave a child a wonderful experience and told him the date and time of my presentation. He had already retired, but he came – and I was delighted.

More telescopes means more observations, confirmations and discoveries. Most radio telescopes, like the currently largest in the world, the Five Hundred Meter Aperture Spherical Telescope (FAST) in China, were designed only to receive signals, but Arecibo’s 305-meter antenna was capable of both receive and transmit. Our best tool for listening and talking to the Universe is now silent.

The last time Arecibo was used for a targeted search for signs of alien technology, called technosignatures, was in 1998 to 2004, as part of the private Phoenix Project, run by the SETI Institute in Mountain View, California. The project observed 800 nearby stars, but did not pick up any transmission. In 2019, NASA restored funding for research on exoplanets and exobiology in order to research technosignatures.

No such project was underway at the observatory when it collapsed, but I wanted to change that. My research students planned to observe star systems with potentially habitable planets for longer than anyone else, and therefore to increase sensitivity to weak signals. We made our last observations of a red dwarf star in early August 2020, just four days before the first of two cable failures that shut down the observatory. Soon after, I became one of dozens of scientists – cosmologists, stellar physicists, atmospheric scientists – who met every week to brainstorm ideas on how to save and improve the telescope. We didn’t give up after the December collapse; we plan to find support to rebuild Arecibo with a new and better telescope.

As a child, I learned from Gerry how a telescope, a moment, a person can impact your life. It took me years of hard work to learn how to use the Arecibo Observatory, and it was difficult for me to see it working in less than a minute. Generations of Puerto Rican scientists are also in mourning.

Although I record most of my observations electronically, I like to keep a written notebook when I am physically with the instruments. January 2020 was the time to start a new one, but with the earthquakes, pandemic, and remote working, I haven’t made a single entry. I plan to start writing again in 2021 – although I will never find that missing year, a year in which we have all lost so much.