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Destruction of Arecibo Observatory an ‘incalculable’ loss for struggling Puerto Rico

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Génesis Ferrer had dreamed of working in the Arecibo Observatory ever since she first met some of its astrophysicists during a high school trip in Puerto Rico.



a tree with Arecibo Observatory in the background

© Provided by NBC News


After hearing them use terms such as “radiation” and “emission,” Ferrer, 21, said she “just fell in love with the entire idea of being able to understand things so far away.” Like many scientists in the U.S. territory, Ferrer can trace back her interest in astrophysics, biophysics and space to that school trip.

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The fourth-year physics student from the University of Puerto Rico, Río Piedras campus, had recently earned a fellowship from the Puerto Rico NASA Space Consortium to study emissions from red dwarf stars using the giant radio telescope in Arecibo. Because of coronavirus restrictions, Ferrer has been accessing the data she needs from the Arecibo Observatory remotely, hoping she would soon be able to finish her investigation in the place where it all started.

Those hopes faded away Tuesday morning when the Arecibo Observatory collapsed. The telescope’s 900-ton receiver platform and the Gregorian dome — a structure as tall as a four-story building that houses secondary reflectors — fell onto the northern portion of the vast reflector dish more than 400 feet below after the main cables holding up the structures broke overnight.

“I was very sad, very disappointed,” Ferrer told NBC News. “I worked so hard to finally get accepted to work in the Arecibo Observatory. And now that I got accepted, I can’t work in it. I felt very sad, not only individually, but I also saw it as a very sad thing for Puerto Rico and the science in Puerto Rico.”

The Arecibo Observatory was the largest radio telescope in the world and a point of pride for Puerto Ricans, whether they were in science or not. About 90,000 islanders and tourists visited the observatory every year, a boon to the region.

During its almost 57 years in operation, the observatory built with money from the U.S. Department of Defense has been at the forefront of space research — and a crucial training ground for space science students.

In August, the observatory started crumbling after an auxiliary cable snapped, causing damage to the telescope’s dish and the receiver platform that hung above it, according to the U.S. National Science Foundation, the federal agency that owns the observatory. In an attempt to prevent “an uncontrolled collapse” in order to “safely preserve other parts of the observatory that could be damaged or destroyed,” the agency said it began its plan to decommission the telescope in mid-November.

“The NSF was taking a long time to do this because they have a series of protocols they have to follow,” said Abel Méndez, director of the Planetary Habitability Laboratory at the University of Puerto Rico, Arecibo campus, and a planetary astrobiologist. “We thought they had an emergency plan that could speed things up.”

But the cables failed before the agency was able to preserve the telescope.

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Young continents were fragile and prone to destruction

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Dec. 2 (UPI) — Earth’s earliest continents were fragile and destruction-prone, according to a new study published Wednesday in the journal Nature.

Earth formed roughly 4.5 billion years ago, but the planet’s infancy — its first 1.5 billion years — and the processes that shaped its continental features are poorly understood.

“This was the time of formation of the first continents, the emergence of land, the development of the early atmosphere and the appearance of primordial life — all of which are the result of the dynamics of our planet’s interiors,” lead study author Fabio Capitanio said in a news release.

For the new study, Capitanio and his colleagues created computer models simulate the conditions of early Earth.

“We show that the release of internal primordial heat, three to four times that of the present-day, caused large melting in the shallow mantle, which was then extruded as magma … onto the Earth’s surface,” said Capitanio, a researcher at Monash in Australia.

According to the models, the pieces of mantle left behind by this process formed the keels of the planet’s first continents. The landforms, however, were dehydrated and rigid.

Simulations suggest the first continents remained weak for billions of years, and were prone to destruction. Early on, Earth’s landforms were easy to melt, making them more malleable, allowing them to became increasingly differentiated.

Over time, this process produced larger and more rigid pieces of mantle, forming what would become the cores of modern continents.

Today, these cores take the form of cratons, the large, stable chunks of mantle and crust found in the interior of Earth’s continents.

The process of early continent formation was essential to the evolution of Earth’s geochemistry and, ultimately, the planet’s biochemistry.

“The emergence of these rigid early continents resulted in their weathering and erosion, changing the composition of the atmosphere and providing nutrients to the ocean seeding the development of life,” Capitanio said.

The new research also explains why so little of Earth’s primordial crust remains. The destruction and incorporation of Earth’s earliest continental crust into the mantle helped reinforce the keel-like chunks of mantle that came to form cratons.

According to Capitanio and his colleagues, these cratons house the earliest evidence of life on Earth, but they make up only a tiny fraction of Earth’s surface.

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Continents prone to destruction in their infancy, study finds

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Earth continents
Credit: Pixabay/CC0 Public Domain

Monash University geologists have shed new light on the early history of the Earth through their discovery that continents were weak and prone to destruction in their infancy.


Their research, which relies on mathematical modeling, is published today in Nature.

The Earth is our home and over its 4,500,000,000 (4.5 billion) year history has evolved to form the environment we live in and the resources on which we depend.

However, the early history of Earth, covering its first 1.5 billion years remains almost unknown and, consequently, poorly understood.

“This was the time of formation of the first continents, the emergence of land, the development of the early atmosphere, and the appearance of primordial life—all of which are the result of the dynamics of our planet’s interiors,” said lead study author ARC Future Fellow Dr. Fabio Capitanio from the Monash University School of Earth, Atmosphere and Environment.

“Reproducing the conditions of the early Earth in computer-generated numerical models, we show that the release of internal primordial heat, three to four times that of the present-day, caused large melting in the shallow mantle, which was then extruded as magma (molten rock) onto the Earth’s surface,” he said.

According to the researchers, the shallow mantle left behind by this process was dehydrated and rigid and formed the keels of the first continents.

“Our results explain that continents remained weak and prone to destruction in their infancy, ~4.5 to ~4.0 billion years ago, and then progressively differentiated and became rigid over the next billion years to form the core of our modern continents,” Dr. Capitanio said.

“The emergence of these rigid early continents resulted in their weathering and erosion, changing the composition of the atmosphere and providing nutrients to the ocean seeding the development of life.”

Dr. Capitanio specialises in investigating the dynamics of the Earth’s tectonics and plate motions to better understand the mechanisms that force single plates or whole-Earth changes.

The work adds to the knowledge on supercontinent formation and its fragmentation into the present-day continents.

The quantitative model used in the study explains the enigmatic melt degrees and layered structures observed in most cratons on Earth.

The process shows that continents remain weak and prone to destruction in their infancy, then progressively melt and differentiate to become stable continents.

This accounts for the transition from the Hadean, covering the first 500 million years of Earth history, in which crust was completely recycled, to the Archean (four to three billion years ago), when rigid continental keels built up and remain preserved through time.

“The geological record suggests that the very early continents did not survive and were recycled in the planet’s interiors, yet this trend dramatically inverted approximately four billion years ago, when the most enduring piece of continents, cratons, appeared,” Dr. Capitanio said.

Only tiny crystals remain from Earth’s earliest continental crust, formed more than 4 billion years ago. The mysterious disappearance of this crust can now be explained. The very process that formed new crust,

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