Your support = more science, more stars, more wonder.<\/strong> Mudball meteorites<\/em> \u2013 or carbonaceous chondrites \u2013 are unique. They are rich in clays, organic compounds and water-bearing minerals. As you might expect, they are generally weaker than stony meteorites. But they\u2019re not always<\/em> as weak as first thought. An international team of scientists has completed a new analysis of the Aguas Zarcas mudball meteorites, which fell near Aguas Zarcas, Costa Rica, in April 2019. The team said on March 31, 2025, that these mudballs were stronger than most, and more of the original space rock survived the impact with Earth\u2019s atmosphere than is typically seen.<\/p>\n The research team published their peer-reviewed results in the journal Meteoritics & Planetary Science<\/em> on March 29, 2025.<\/p>\n The Aguas Zarcas mudball meteorites fell in Aguas Zarcas, Costa Rica, on April 23, 2019. For scientists, it was one of the largest meteorite hauls of its kind. Lead author and astronomer Peter Jenniskens, at the SETI Institute and NASA Ames Research Center, said:<\/p>\n 27 kilos (60 lbs) of rocks were recovered, making this the largest fall of its kind since similar meteorites fell near Murchison in Australia in 1969.<\/p>\n<\/blockquote>\n Geologist Gerardo Soto at the University of Costa Rica in San Jos\u00e9, paraphrasing astronaut Neil Armstrong on the moon, added:<\/p>\n The recovery of Aguas Zarcas, too, was a small step for man, but a giant leap for meteoritics. 76 papers have since been written about this meteorite. The fall of Aguas Zarcas was huge news in the country. No other fireball was as widely reported and then recovered as stones on the ground in Costa Rica in the last 150 years.<\/p>\n<\/blockquote>\n PRESS RELEASE: buff.ly\/wygr7exIn April 2019, rare primitive meteorites fell near Aguas Zarcas in northern Costa Rica. Now, an international team of researchers describe the circumstances of the fall and show that mudball meteorites are not necessarily weak. ? ?<\/p>\n \u2014 SETI Institute (@setiinstitute.bsky.social) 2025-03-31T19:05:10.047Z<\/p>\n<\/blockquote>\n You would think that meteorites containing clays, organics and water would be weaker than meteorites made of only stone. And you would be right. But the Aguas Zarcas meteorites showed that sometimes, even mudballs can be stronger than anticipated. The original space rock plunged into Earth\u2019s atmosphere at an almost vertical angle. It came from a west-northwest direction at 9 miles per second (14.6 km\/s). Indeed, the intense heat did ablate, or melt, much of the rock. However, it didn\u2019t fragment as much as expected. Jenniskens explained:<\/p>\n It penetrated deep into Earth\u2019s atmosphere, until the surviving mass shattered at 16 miles (25 km) above the Earth\u2019s surface, where it produced a bright flash that was detected by satellites in orbit.<\/p>\n<\/blockquote>\n That shattering produced the meteorites found later on the ground.<\/p>\n Many of the meteorites remained intact since they landed on grassy surfaces in jungles. They also had unusual shapes and striking colors. Co-author and meteoriticist Laurence Garvie at the Buseck Center for Meteorite Studies at Arizona State University said:<\/p>\n The Aguas Zarcas fall produced an amazing selection of fusion-crusted stones with a wide range of shapes. Some stones have a beautiful blue iridescence to the fusion crust.<\/p>\n<\/blockquote>\n The fact that the meteorites survived as much as they did surprised scientists. They were stronger than expected, as Jenniskens noted:<\/p>\n Other meteorites of this type are often described as mudballs, as they contain water-rich minerals. Apparently, that does not mean they are weak.<\/p>\n<\/blockquote>\n So how did these mudball meteorites survive the impact as much as they did? The scientists said there were a couple of reasons. The original Aguas Zarcas space rock \u2013 the parent body of the smaller meteorites \u2013 didn\u2019t have many collisions with other space rocks. The researchers estimated the last one to be about 2 million years ago. It also didn\u2019t have the kinds of cracks in it that weaken many space rocks. So it was a bit stronger than unusual \u2013 at least for a mudball \u2013 right from the start.<\/p>\n The space rock that hit Earth\u2019s atmosphere \u2013 about 24 inches (60 cm) in size \u2013 originated from a larger asteroid. The researchers said the asteroid was likely in the main asteroid belt between Mars and Jupiter. Jenniskens said:<\/p>\n We can tell that this object came from a larger asteroid low in the asteroid belt, likely from its outer regions. After getting loose, it took 2 million years to hit the tiny target of Earth, all the time avoiding getting cracked.<\/p>\n<\/blockquote>\n Cosmochemist Kees Welten at UC Berkeley in California added:<\/p>\n We know of other Murchison-like meteorites that broke off at approximately the same time, and likely in the same event, but most broke much more recently.<\/p>\n<\/blockquote>\n Bottom line: The Aguas Zarcas mudball meteorites, which landed in Costa Rica in 2019, were stronger than expected. A new study shows that not all mudballs are weak.<\/p>\n Source: Orbit, meteoroid size, and cosmic ray exposure history of the Aguas Zarcas CM2 breccia<\/p>\n Via SETI Institute<\/p>\n Read more: Mud ball meteorites rain down in Costa Rica<\/p>\n Read more: How do meteorites survive their fiery journey to the ground?<\/p>\n <\/div>\n
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Not all mudball meteorites are weak<\/h3>\n
The Aguas Zarcas mudball meteorites<\/h3>\n
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Mudball meteorites were stronger than expected<\/h3>\n
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An amazing collection of stones<\/h3>\n
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Why were these meteorites so strong?<\/h3>\n
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