The Aguas Zarcas meteorite contains stardust that predates the Sun, providing invaluable insights into the early universe and the origins of our Solar System.
TL;DR
In 2019, a rare meteorite fall in Aguas Zarcas, Costa Rica, scattered fragments across the village, some of which are valued higher than gold. These fragments, carbonaceous chondrites, contain organic molecules like amino acids, believed to be remnants from the Solar System’s early days. Their scientific value is immense, offering insight into the origins of life. Despite the intense interest from scientists, many fragments were sold to private collectors for over $400 per gram, surpassing the price of gold.
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On the night of April 23, 2019, a bright fireball streaked through the skies over Costa Rica, emitting an unusual blend of orange and green. Marcia Campos Muñoz was lounging on her couch in her pajamas, watching TV, when she heard a low, rumbling sound. Startled, she stepped outside to quiet her barking dog, Perry, and check on the cow pastures surrounding her home in Aguas Zarcas, a small village nestled within the tropical rainforest. Seeing nothing unusual, she went back inside, only to be shaken moments later by a loud crash on her back terrace.
She immediately called her father, brother, and eldest son, who hurried over. They found a hole the size of a grapefruit punched through the zinc roof and a smashed plastic table, a remnant of her daughter’s quinceañera celebration. On the floor were pieces of a mysterious, coal-black rock, still warm to the touch. At the same time, Campos Muñoz’s phone buzzed with WhatsApp messages from friends who had seen fireballs in the sky and debris falling onto fields and farms. Her family joined the online frenzy, sharing photos of the large stone that had crashed through their roof. Soon, a local journalist visited to film the scene, streaming it live on Facebook.
This was just the beginning. A space rock the size of a washing machine had disintegrated over the village, and the global scientific community was about to take notice.
While meteorites aren’t rare, with thousands surviving entry into Earth’s atmosphere each year, meteorite falls—when a meteorite’s descent is witnessed and its landing site identified—are unusual. Only 1,196 such events have been documented. But this one was extraordinary. The fragments of the Aguas Zarcas meteorite, as they came to be known, were a carbonaceous chondrite—an ancient remnant from the early days of the Solar System. Unlike most meteorites, which are composed of rock or metal, carbonaceous chondrites are rich in organic molecules, including amino acids, the building blocks of life. Some scientists even believe that meteorites like Aguas Zarcas may have delivered these essential components to Earth billions of years ago.
The meteorite’s significance became clear right away, drawing comparisons to the legendary Murchison meteorite that exploded over Australia in 1969. Murchison was found to contain nearly 100 different amino acids, some used by organisms on Earth and others rare or absent in known life. These discoveries helped kickstart the field of astrobiology, and now Aguas Zarcas, with its fresher fragments, offered scientists the opportunity to apply modern techniques to study and preserve these ancient relics.
If Aguas Zarcas remained uncontaminated, scientists could extract valuable data spanning three ancient periods: the time before the Solar System existed, the early formation of the Solar System, and the period when these particles began to coalesce into larger bodies, including planets. However, the clock was ticking. With the rainy season approaching in Costa Rica, the meteorite fragments were at risk of being damaged by moisture, which would degrade their ancient organic compounds.
The day after the meteorite fall, meteorite dealer Mike Farmer, based in Tucson, Arizona, stumbled upon a Facebook post featuring a photo of the fragments. Recognizing their value immediately, he packed $50,000 in cash and flew to Costa Rica, ready to buy. By the time he arrived, a meteorite hunting frenzy had already begun. Villagers scoured the land for fragments, and collectors from around the world flocked to the area. Prices skyrocketed, with some stones fetching more than $400 per gram—more than the price of gold.
Meanwhile, scientists from the University of Costa Rica, eager to study the fragments, were among the first on the scene. They carefully documented the meteorite, recognizing its extraordinary age and scientific value. However, with limited resources, they couldn’t compete with the high prices offered by collectors, and many fragments were sold to private individuals, leaving the country.
Around the world, meteorite laws vary, and while some countries strictly regulate their sale, in Costa Rica and the U.S., they can be freely bought and sold. This dynamic fuels the market, encouraging people to hunt for meteorites, but it also raises concerns about losing valuable scientific material.
Despite the challenges, the Aguas Zarcas meteorite’s scientific potential is immense. Researchers are analyzing its fragments for clues about the early Solar System, using modern techniques to search for proteins, amino acids, and other organic compounds that may have played a role in the origins of life on Earth.
In the months following the fall, Aguas Zarcas was officially recognized and classified, cementing its place in history. Scientists continue to uncover its secrets, offering a glimpse into a time long before our planet was formed.
The Murchison meteorite contains grains as old as 7.5 billion years, although most are only a few hundred million years older than the Solar System. If similar patterns are found in the Aguas Zarcas meteorite, it could suggest that a generation of stars formed about 7 billion years ago, which later contributed dust to the Solar System. Some astronomers believe that a wave of star formation, possibly triggered by a galactic event, occurred around this time.
Researchers at the Field Museum are studying calcium-and aluminum-rich inclusions in Aguas Zarcas. These inclusions are the first minerals to have condensed in the protosolar disk and record the young Sun’s violent activity through surges of radiation that left traces of helium and neon. Meanwhile, teams at Brown University and Arizona State University are using specialized equipment to capture volatile organic compounds, some of which escape at room temperature. They are also searching for more stable organic compounds, such as amino acids.
At NASA Goddard, a team discovered hundreds of different amino acids in Aguas Zarcas, comparable to those found in the Murchison meteorite. They are now working on detecting peptides, which would provide further insight into prebiotic space chemistry. However, ASU researchers have struggled to find amino acids, possibly due to the meteorite’s heterogenous composition, which may have experienced varying levels of water and heat alteration.
Amino acids, like isovaline, come in two mirror-image forms, but life on Earth uses only left-handed amino acids. Some theories suggest that this preference arose by chance on Earth, while others argue it may have originated in space. Aguas Zarcas, like other meteorites, shows a slight left-hand bias, suggesting the preference may have been inherited from space-borne molecules influenced by polarized light from nearby stars.
Scientists are also studying Aguas Zarcas to understand early Earth’s atmosphere. At the University of California, Santa Cruz, experiments involve baking meteorite fragments to analyze gases released, which may offer clues about the role of asteroids in forming Earth’s water-rich atmosphere.
Aguas Zarcas is being studied alongside pristine samples from asteroids Ryugu and Bennu, collected by the Hayabusa2 and OSIRIS-REx missions, respectively. These missions provide uncontaminated material for analysis, while Aguas Zarcas offers a useful comparison.
For residents of Costa Rica’s Aguas Zarcas, the meteorite was an unexpected financial windfall. Ruddy Valerio Díaz, struggling financially, sold 300 grams of meteorite stones to pay off debts and start a business, naming his restaurant “Tilapias Rancho El Meteorito.” Other locals also benefited, using their earnings to renovate homes, expand farms, and buy new possessions. Despite much of the meteorite being sold internationally, some pieces remain in Costa Rica, with scientists hopeful that more may eventually return to local institutions.
For María Campos Muñoz, whose roof was damaged by a falling meteorite, the event has become part of her family’s history. She still owns the piece that crashed through her roof, and while collectors have offered to buy it, she hopes to see it in an exhibition one day. The damage to her home has become a symbol of the meteorite’s impact, drawing curious visitors and leaving a lasting impression on her life.