On July 16, 2024, a daytime meteor shook New York City with a sonic boom as it passed just south of the Statue of Liberty. A short time later, a more than two-pound meteorite crashed through the roof of a house in the town of Hillsborough, New Jersey.
Now, an international team, including scientists at Lawrence Livermore National Laboratory (LLNL), has analyzed that meteorite. Their results - which indicate that the meteor was once a part of an ancient, briny asteroid - appear in the journal Science Advances.
"A forensic study of the fragments revealed that they contained preserved bits from near the surface of a small primitive asteroid where it experienced concentrated salty fluids - a process not previously known from this type of proto-planet world," said lead author and meteor astronomer Peter Jenniskens of the SETI Institute and NASA's Ames Research Center.
Originally the size of a heavy piece of luggage, the meteor entered the Earth's atmosphere at 32,000 miles per hour. Observers from New York, New Jersey, Connecticut, Rhode Island and Pennsylvania reported seeing it and feeling the shockwave.
The rock was fragile and quickly broke into pieces during its atmospheric passage. Only one piece was recovered - because it hit a house. The owner was present, heard a large crash and found a hole in the ceiling. He immediately preserved and documented the entire scene.
From there, some of the "Hillsborough meteorite" sample made its way to LLNL, where the team measured inorganic isotopic signatures like titanium.
"At LLNL, we can measure isotope ratios at state-of-the-art-precision to understand the history of a sample. That sample can be a meteorite, or it could be illicit nuclear material," said author and LLNL scientist Greg Brennecka. "The ability to accurately and precisely measure isotopic compositions allows us to reconstruct the past and determine the origin of various objects, whatever they may be."
Those measurements helped determine what kind of meteorite crashed through the New Jersey home: a CM-type carbonaceous chondrite. This type of primitive meteorite originates from water-rich asteroids, most likely from the outer regions of the early solar system.
Within the meteorite, the international collaboration found small, salt-rich fragments that likely originated from a near-surface region of its parent asteroid. There, liquid water evaporated and precipitated salts from the brine.
Some studies suggest that carbonaceous chondrites delivered organic matter to the early Earth. The high concentration of salt in briny fluids can potentially assist in creating molecules crucial to life, like amino acids.
"This is one of the most pristine meteorites that we currently have, and it tells us a lot about the parent body from which this particular meteorite class derived," said author and LLNL scientist Jan Render. "Understanding how these asteroids formed gives us insight into the origin and delivery of organic molecules to Earth and how common they may be in other stellar systems to potentially provide the ingredients for life."
For the scientists at LLNL, this sample was a fascinating peek into the early solar system and a rare treat enabled by a homeowner with quick thinking.
"It was very important (and impressive) that the homeowner was able to collect the sample the way he did to best preserve it for scientific study," said Brennecka. "This is a rare type of sample, and it fell in a spot that made it possible to study. But much of this work would not have been possible or meaningful without the preservation by the homeowner.
"If you are ever lucky enough to have a meteorite go through the roof of your house, do science a favor by quickly collecting pieces of it in a clean glass jar and sealing it up."
