A preliminary investigation into why the famous alien-hunting Arecibo Observatory telescope collapsed in December has provided officials with clues to what caused the catastrophic event.
Forensic investigators were recently brought to the scene to examine the fallen giant, where they focused on the auxiliary and main cables that had snapped.
The teams found a manufacturing error with the auxiliary cables, in which the socketing procedure was not done properly and may have led to the degradation of the structure.
One of the supporting cables had slipped out of its socket in August 2020 and before officials could repair it, a second cable snapped three months later – and then the telescope came tumbling down in December.
Scroll down for video
A preliminary investigation into why the famous alien-hunting Arecibo Observatory telescope collapsed in December has provided officials with clues to what caused the catastrophic event
Arecibo collapsed December 1, 2020 when a cable holding up a 900-ton receiver platform snapped around 8am local time that morning and sent the massive structure hurling onto the reflector dish more than 400 feet below.
Arecibo Observatory suffered another failure in August when an auxiliary cable broke that resulted in a 100-foot gash on the 1,000-foot-wide dish and damaged the receiver platform that hung above it.
Then a main cable failed in early November that sealed the iconic telescope’s fate – officials were set to shut it down after 57 years of service.
Ramon Lugo, director of the Florida Space Institute at the University of Central Florida and manager of Arecibo, said he speculated the telescope was due to collapse a few days before the event took place.
The teams found a manufacturing error with the auxiliary cables, in which the socketing procedure was not done properly and may have led to the degradation of the structure. One of the supporting cables had slipped out of its socket in August 2020 (pictured)
Arecibo collapsed December 1 (pictured) when a cable holding up a 900-ton receiver platform snapped around 8am local time that morning and sent the massive structure hurling onto the reflector dish more than 400 feet below
The observatory team is now working to uncover specific details to what led to the collapse, as first reported on by Space.com.
Francisco Cordova, observatory director, said during a panel discussion: ‘The site cleanup and the debris removal really is ongoing.’
‘In general, I think that is moving in the right direction.’
Two forensic investigations are evaluating the debris, with one focusing on the auxiliary cables and the other on the main cables.
The auxiliary cables, 12 in total, where added to the telescope’s structure in the 1990s when the hanging dome was constructed.
One of these was also the first to fail in August when it slipped from the socket that connected it to one of the three surrounding support towers.
‘Preliminary investigation has revealed that there was a manufacturing error in those cables — in particular, the socketing procedure wasn’t done appropriately, and that led to advanced degradation of that particular structural element,’ Cordova said.
Two forensic investigations are evaluating the debris, with one focusing on the auxiliary cables and the other on the main cables. The auxiliary cables, 12 in total, where added to the telescope’s structure in the 1990s when the hanging dome was constructed
The other investigation is looking into the main cables, which were part of the telescopes early 1960s construction, and one had failed in November. Engineers say that that specific cable was holding only 60 percent of the weight it should have been able to withstand
‘But the final forensics investigation is still to be completed.’
The other investigation is looking into the main cables, which were part of the telescopes early 1960s construction, and one had failed in November.
Engineers say that that specific cable was holding only 60 percent of the weight it should have been able to withstand and are separating debris that could be used in this investigation, as well as the one into the auxiliary cables.
‘Certainly, there’s typically not a single item that contributed but a multitude of items that contributed to the particular failure,’ Cordova said.
Arecibo Observatory is famous for detecting whirling pulsars, capturing geological features of Mars and helping astronomers discover the near-Earth asteroid Bennu. Pictured is the telescope in 2016
Although the investigations are looking at Arecibo’s structure, Cordova is aware that natural weather events may have played a role.
In 2017, Hurricane Maria ripped through Puerto Rico and tore pieces off from the telescope.
And just last year, more than 10,000 earthquakes hit the area.
‘Basically, we were shaking the entire time; that certainly could have been a factor,’ Cordova said. ‘That’s being still analyzed by the engineering teams.’
Arecibo Observatory is famous for detecting whirling pulsars, capturing geological features of Mars and helping astronomers discover the near-Earth asteroid Bennu, along with making an appearance in the 1995 James Bond film GoldenEye.
The giant telescope was also used in programs that search for extraterrestrial intelligence (SETI) because its location provided scientists access to one-third of the cosmos.
Arecibo Observatory is famous for detecting whirling pulsars, capturing geological features of Mars and helping astronomers discover the near-Earth asteroid Bennu, along with making an appearance in the 1995 James Bond film GoldenEye (pictured)
Because Arecibo has played a key role in major space discoveries, Puerto Rico’s government is also working to restore it.
Last month, Governor Wanda Vázquez signed an executive order approving $8 million to help rebuild the renowned telescope.
The order states reconstructing Arecibo is ‘a matter of public policy,’ along with declaring the observatory site a historic zone.
The $8 million is set to be used for removing and disposing of the debris and the design of the new telescope.
ARECIBO OBSERVATORY HISTORY
1963: Arecibo Ionospheric Observatory Commissioned for service on November 1 for $9.7 million.
1965: One of its first accomplishments was establishing the rotation rate of Mercury, which turned out to be 59 days rather than the previously estimated 88 days.
1968: Sporadic radio pulses from the direction of the Crab Nebula supernova remnant found at Green Bank were shown by Arecibo to come from a 33-ms period pulsar situated at the center of the nebula.
1974: New high precision surface reflector installed, planetary radar transmitter installed.
1974: The first pulsar in a binary system was discovered, leading to important confirmation of Einstein’s theory of general relativity and a Nobel Prize 1993 for astronomers Russell Hulse and Joseph Taylor.
1974: On 16 November, the ‘Arecibo message’ was broadcast into space toward the globular star cluster M13 25,000 light years away.
The message’s main purpose was to demonstrate the capabilities of newly installed equipment in the upgraded radio telescope and was an attempt to contact extraterrestrial intelligence.
1979: A large, anomalous travelling ionospheric disturbance (that is, an upper atmosphere wave) moving southeast to northwest was detected in the early morning hours – something researchers had never before witnessed. Data helped define the probable cause as an air nuclear blast over the Indian Ocean.
1981: First radar maps of the geologic surface of Venus are produced.
1982: The discovery of strong ‘megamaser’ emission from the hydroxyl (OH) molecule in the starburst galaxy Arp 220 (IC 4553).
1982: The discovery of millisecond pulsars, which rotate several hundred times per second. This demonstrated the existence of two classes of pulsars – the millisecond pulsars and the slower-rotating pulsars, which rotate about once per second.
1989: The first measurement of hydrogen escape flux from Earth is presented, based on velocity distribution measurements of the hydrogen airglow emission in the upper atmosphere.
Early 90s: The first planets outside the solar system were discovered around Pulsar B1257+12, a rapidly rotating pulsar with three Earth-like planets in orbit.
1992: In October, ice is discovered in shadowed craters at Mercury’s north pole. Later observations show ice in south pole craters as well.
1996: A layer of helium ions is shown to be a common, but previously unrecognised feature in the low-latitude ionosphere near 600 km.
1998: Arecibo Observatory ‘found’ the Solar and Heliospheric Observatory (SOHO) spacecraft on July 28, after it lost communications with European Space Agency and NASA,. by bouncing a radar signal off the satellite. SOHO’s mission was resumed and continues to produce data today.
May 2000: Radar Observations of Asteroid 216 Kleopatra reveal a ‘dog bone’ shaped metal-rich object.
September 2000: Discovery that 2000 DP107 was the first near-Earth asteroid identified by radar as a binary system. The primary is roughly spherical with a diameter of a half mile and the smaller secondary, which orbits it in 1.8 days, is about 1000 feet.
2003: Evidence for hydrocarbon lakes on the Saturn satellite Titan is established using the Observatory planetary radar.
April 2004: Installation of the Arecibo L-band Feed Array, enabling a wide variety of astronomical surveys including discovering pulsars, mapping the gas in our Galaxy, and searches for other galaxies.
2005-2012: Radar imaging of Mars reveals lava flows and near-surface geologic features not seen in visible images. This provides new insights into Mars surface geology.
2006: Search for water ice in the permanent shadow of the lunar Shackleton Crater disputes evidence for water ice on the lunar surface.
October 2006: Radar images of the south pole of the moon reveal no evidence for thick deposits of ice.
November 2006: Radar images of binary asteroid (66391) 1999 KW4 in May 2001 and again in June 2002 reveal exotic physical and dynamical properties which may be common among near-Earth binaries.
March 2007: Radar images of Mercury reveal features to be studied further by the Messenger spacecraft over the next several years.
2007: The near-Earth asteroid 2005 PH5 was observed to be increasing in spin rate, due to non-uniform absorption and emission of solar radiation.
2007: Previously undetected radio lines of the molecule hydrogen cyanide (HCN), and the presence of the molecule methanimine (CH2NH), were recently discovered in the distant ‘starburst galaxy’ Arp 220.
February 2008: Discovery of the first triple asteroid system among the near-Earth asteroids. The asteroid, 2001 SN263, is about 1.5 miles in diameter, with two moons orbiting it.
2008–2012: Observations discover a radio outburst in the nearby galaxy NGC 660, ten times brighter than a radio supernova.
2011: Observations of brown dwarfs find the coldest star to show radio emission.
November 2011: Radar imaging of near-Earth asteroid 2005 YU55, which made a very close flyby. This dark, spheroidal asteroid was found to be about 1,148 feet in diameter.
2012: An ion-neutral chemistry model is developed to successfully describe thin layers of neutral metal atoms at above 62 miles altitudes.