December 1st, 2020
The Arecibo Observatory in Puerto Rico, a world-famous 1,000-foot-wide radio telescope by means of which main discoveries in astronomy and astrophysics had been made, collapsed on the morning of Tuesday, December 1, after one in all its principal cables broke on November 6.
That cable’s collapse occurred three months after the telescope’s reflector dish was broken in August of this 12 months when an auxiliary cable slid out of its socket in one of many observatory’s towers, leaving the dish with a 100-foot gash and inflicting the collapse of different cables when it fell.
An engineering group was within the means of figuring out the reason for the primary cable break and understanding a restore plan when the second cable, this time a principal one, collapsed onto the dish, additional damaging each it and different cables.
Following the second accident, the Nationwide Science Basis (NSF), which owns Arecibo, decided that repairing the telescope may trigger additional catastrophic collapse that posed a risk to the lives of the technicians who could be doing the work.
In a bid to save lots of the telescope, supporters, together with Puerto Rico’s Congressional consultant Jenniffer Gonzalez, organized a proper petition to the White Home asking the federal authorities to ship the Military Corps of Engineers to judge whether or not Arecibo might be stabilized and finally repaired.
At 6:55 AM EST on Tuesday, the telescope’s 900-ton instrument platform, suspended through cables related to a few towers, fell 450 toes (137 meters) onto already broken reflector dish.
In a public assertion, the NSF stated, “Preliminary findings point out that the highest part of all three of the…telescope’s help towers broke off. Because the 900-ton instrument platform, fell, the telescope’s help cables additionally dropped. Preliminary assessments point out the observatory’s studying heart sustained vital harm from falling cables.”
No accidents resulted from the collapse.
Iconic Historical past:
Arecibo opened in 1963 after three years of development. Over 57 years, it has been one of the crucial productive telescopes in each the quantity and scope of discoveries made utilizing it. The observatory has been used to review a variety of fields in astronomy and astrophysics starting from pulsars to near-Earth asteroids to quick radio bursts.
Only one 12 months after Arecibo opened, a analysis group led by Gordon Pettingill used the telescope to find out that Mercury’s rotation interval is 59 days relatively than the 88 days beforehand believed.
The primary exoplanet ever found was discovered with Arecibo in 1992. One 12 months later, scientists Russell Hulse and Joseph Taylor used the observatory to seek out the primary proof of gravitational waves, a phenomenon predicted by Einstein’s idea of normal relativity, by finding out a binary pulsar system, incomes them that 12 months’s Nobel Prize in Physics.
In an try to speak with any present extra-terrestrial civilizations, scientists in 1974 used Arecibo to ship an interstellar radio message.
A serious vacationer attraction, Arecibo obtained hundreds of tourists yearly and actively took half in public outreach and science schooling, motivating many to pursue careers in engineering and astronomy.
Arecibo was additionally a well-liked tradition icon, having been featured within the 1995 James Bond movie GoldenEye and within the 1997 movie Contact. The latter was primarily based on a novel by Carl Sagan.
Throughout its 57 years of operation, Arecibo was broken on a number of events, typically by earthquakes and hurricanes. In 2014, an earthquake broken one other of its principal cables, which was subsequently repaired. In 2017, Hurricane Maria broken each the dish and one of many antennas.
A number of earthquakes hit Puerto Rico in January of this 12 months, inflicting the observatory to shut for a number of days.
Repairs of harm from Hurricane Maria had been nonetheless underway when the auxiliary cable broke in August 2020, presumably as a result of harm from Tropical Storm Isaias, which had simply handed over Puerto Rico.
Because the principal cable collapse final month, satellite tv for pc photos have revealed the telescope to be extra broken than beforehand thought. Pictures commissioned by the journal Nature present the dish to be damaged in half, with massive gouges in its central space.
The primary cable was discovered to have damaged at 60 p.c of what ought to have been its minimal breaking energy throughout good climate, indicating the observatory’s cables had been weaker than beforehand thought, as a result of degradation over time. Utilizing drones, engineers found extra wire breaks in a number of main cables.
“In keeping with engineering assessments, even makes an attempt of stabilization or testing the cables may lead to accelerating the catastrophic failure. Engineers can’t inform us the security margin of the construction, however they’ve suggested NSF that the construction will collapse within the close to future by itself,” said Ralph Gaume, director of the NSF‘s astronomy division.
Plans had been underway to improve one of many observatory’s antennas to extend its sensitivity. These had been subsequently suspended when the NSF determined to conduct the managed demolition.
Shedding Arecibo is a significant blow to astronomers and astrophysicists worldwide. Whereas a number of the science finished there will be transferred to different observatories, different initiatives will be finished solely with its distinctive devices.
Different, smaller elements of the observatory, corresponding to two lidar devices that examine the ambiance by firing lasers into it, won’t be destroyed. The NSF hoped to protect the guests’ heart in addition to different buildings on the location, however the fates of these are unclear following the newest collapse.
The NSF emphasizes security as its prime precedence and says it’s concerned about serving to the scientific neighborhood within the wake of Arecibo‘s loss in addition to persevering with its robust working relationship with Puerto Rico.
“Prime priorities are sustaining security on the web site, conducting an entire harm evaluation as rapidly as potential, and taking motion to include and mitigate any environmental harm attributable to the construction or its supplies, the NSF assertion stated.
“Whereas the telescope was a key a part of the ability, the observatory has different scientific and academic infrastructure that NSF will work with stakeholders to carry again on-line.”
Ashley Zauderer, Arecibo program director, praised the neighborhood of researchers and staff who repeatedly got here collectively to ensure work on the web site continued within the wake of the earthquakes, hurricanes, and the COVID pandemic.
“There’s an extremely various and superb group of scientists and devoted employees and engineers on the observatory, and I imply, I feel it’s their ardour to proceed to discover, to be taught, and that’s the true coronary heart and soul of Arecibo,” she stated.
Laurel Kornfeld is an novice astronomer and freelance author from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass Faculty, Rutgers College, and earned a Graduate Certificates of Science from Swinburne College’s Astronomy On-line program. Her writings have been revealed on-line in The Atlantic, Astronomy journal’s visitor weblog part, the UK Area Convention, the 2009 IAU Basic Meeting newspaper, The Area Reporter, and newsletters of varied astronomy golf equipment. She is a member of the Cranford, NJ-based Newbie Astronomers, Inc. Particularly within the outer photo voltaic system, Laurel gave a short presentation on the 2008 Nice Planet Debate held on the Johns Hopkins College Utilized Physics Lab in Laurel, MD.