Address Arecibo Observatory PR-625, Arecibo, 00612, Puerto Rico

Since its creation, the Arecibo Observatory was used to collect radio astronomical, terrestrial aeronomy and planetary radar data for world scientists.

In order to use it, it was mandatory to apply to an independent committee. Thus, the resources were used wisely.

With a diameter of 305 meters, the main antenna was, until 2016, in first place in the ranking of the largest structures of this type in the world, before being overtaken by the FAST located in China.

Several discoveries are linked to the radio telescope. In 1964, Gordon Pettengill’s team proved that Mercury’s rotation period is 59 days instead of 88 as previously thought. In 1974, the radio telescope discovered PSR B1913+16, the first binary pulsar, thus testing general relativity. In 1992, water ice was detected at the poles of the planet Mercury.

Another funny detail, in 1974, a message was sent from the radio telescope. It contains 1,679 bits of data to the globular cluster M13, which is about 25,000 light years away. The data is a bitmap image of 23 pixels by 73 pixels including numbers, chemical formulas and raw images of a man and the telescope itself.

Fall and end. In August 2020, a cable snapped, causing a gash in the telescope’s reflector. In November, another cable snapped, causing further damage and more cables to fall. The radio telescope is put out of service, any attempt to repair it being much too dangerous. On December 1, the radio telescope collapsed completely, marking the end of a giant in astronomy.