A souvenir from space
Portland State students now have the opportunity to see a rare meteorite, big enough to smash through a house to the ground.
This meteorite is a stone-like mass as big as three basketballs but very dense – it weighs more than 500 pounds. It is on display during office hours on a sturdy table in the Geology department, 17 Cramer Hall basement. It has an internationally approved name, Brahin, named for the city in Belarus, formerly in the Soviet Union.
Smaller pieces of this meteorite were found in 1810 and this large piece in 1819.
The rock formation is of the type known as a pallasite.
“It’s a rare type,” said Alex Ruzicka, assistant professor in planetary sciences and meteorites, and one of three individuals involved in PSU’s Cascadia Meteorite Laboratory. The others are Melinda Hutson, an adjunct professor in geology, and Dick Pugh, a retired high school teacher.
Regarding the Brahin pallasite, Ruzicka said, “This is as rare as it gets. There’s not much of this type hitting earth. The only other pallasite he knows of is a slice of one in the American Museum of Natural History.
Brahin actually is on loan from Edwin Armstrong, a dealer in meteorites at ET Meteorites of Lake Oswego. Armstrong would like to sell the meteorite, perhaps to a wealthy philanthropist who would later donate it to a museum. Meanwhile, it is getting exposure to potential buyers at Portland State, rather than gathering dust in storage.
The pallasite is rare because it is composed of two substances from deep within the core of the asteroid. Part of this is alivine, a gem quality substance which can be employed as a gemstone called peridot. The other substance is the heavier part of the meteorite, a naturally-created steel alloy.
Ruzicka said this natural steel is also what forms the core of the earth.
“Studying a pallasite gives us information about what it might be like inside the earth,” he said.
He speculated as to what Brahin may have looked like as it streaked toward earth as a meteor.
“It likely would have been seen as a tremendously bright object,” he said. “Brighter than the full moon.” As it heated up from the friction of the air it would have started breaking up, making different trails in the sky, probably as many as 10 or 12 pieces.
Had it fallen on a car, he said, “It would have taken the whole car.” If it had fallen in a populated city like Portland, “it probably would have destroyed a good portion of someone’s house. It would take out anything it hits directly.”
Meteorite dealing has become a business. It is especially favored by desert Bedouins. Finding a meteorite in a desert is easier than finding it in the woods or mountains.
Oregon is not a meteorite-heavy state. Only four meteorites have ever been recovered in Oregon, and no pallasites. A very small octahedrite was found in 1952 near Klamath Falls. Fragments of chrondite fell on a police officer’s house in Salem on May 11, 1981. The first meteorite found was an octahedrite, discovered at Sam’s Valley in Jackson County in 1894.
But the biggest, Ruzicka revealed, was the 15-ton Willamette Stone, also an octahedrite. It was found in 1902 on property owned by Oregon Steel Co. near what was then the town of Willamette, now incorporated into West Linn.
The Oregon Steel employee who found the stone attempted to assert ownership of it. The case eventually went to the Oregon Supreme Court, which ruled that meteorites belong to the people who own the land the meteorite fell on. The stone was sold to a wealthy philanthropist, who donated it to the American Museum of Natural History.
The Cascadian Laboratory does not maintain its own museum. Some of its exhibits, along with other mineral exhibits, may be viewed at the Rice Northwest Museum of Rocks and Minerals. It is located in the Hillsboro area. On Highway 26, take the Helvetia/Shute Rd. exit and head north.
The display of a heavy meteorite at Portland State brings up an old question. Why did all the dinosaurs suddenly disappear? Through the years, many explanations have emerged but lately it has been argued that a huge meteorite wiped out the beasts. Is this likely? “Probably so,” said Alex Ruzicka, assistant professor who serves as director of the PSU Cascadia Meteorite Laboratory. But how can just one big meteorite, no matter how big, create so devastating an effect? Ruzicka pointed out some consequences of a huge meteorite that might not occur to the casual inquirer. Such a gigantic meteorite does exist. It hit the earth probably 66 million years ago in the Yucatan area of Mexico. It is now covered with sediment but drillings have confirmed its existence. As Ruzicka explained, a meteorite that big would be creating almost unbelievable heat as it crashed through the earth’s atmosphere. “Any organism in the area would be vaporized,” he said. The heat would likely set forests afire throughout the globe. The impact would create a tremendous dust cloud blocking all sunlight, killing plants and starving any surviving herbivorous dinosaurs as well as the carnivores who fed on them. “The climate would be much cooler for a decade or so,” he elaborated, further impacting the dinosaur population, if any still existed. “The rain would probably be very acidic,” he surmised, meaning death to plant life. The impact created evidence of great tsunami waves that have been found in Texas and would have assured further devastation. This wasn’t the earliest such environmental disaster recorded, Ruzicka revealed. “There was an even bigger extinction 250 million years ago,” he said. That would have occurred in the Permian age, before dinosaurs became the dominant species. The cataclysm of 66 million years ago meant that most species that survived lived underground or in the water, Ruzicka said. “It changed the course of evolution on earth. It enabled the mammals to become dominant.” |
