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UB students huddled in the Hochstetter Hall volcanology lab, passing around a plexiglass disk.

Inside was what at first glance appeared to be unmarketable pebbles and dust but was actually some of the oldest material in our solar system: moon rocks.

“You’re never going to have an older rock in your hand, unless you pick up a meteorite,” Tracy Gregg, professor and chair of the Department of Earth Sciences, stressed to students as the protective casing passed through their hands. “Just take a minute to appreciate that.”

Anywhere from 3.5 to 4.2 billion years old, the rock samples were loaned to Gregg by NASA as part of its Lunar and Meteorite Sample Education Disk Program, which gives educators a chance to use these rare samples in their classrooms.

They’re among the 842 pounds of material brought back from the lunar surface by the Apollo missions. While most of this rock, soil and dust remain in cold storage, the material that has been studied has informed and fascinated scores of researchers and students for decades. 

“They made the descriptions we read in the literature tangible,” said geology graduate student Cassaundra Huggins.

Calling the rocks a “public resource and national treasure wrapped up into one,” Gregg said they demonstrate to students that their earth sciences knowledge extends to much more than just Earth. 

“They can look at these rocks and recognize that the fundamental building blocks are the same,” she said. “It seems like what makes a planet a planet holds true throughout our solar system. There’s something reassuring about that.”

The rocks are perhaps most valuable in what they can tell us about the early Earth. Our celestial neighbor is believed to have formed after a giant object collided with the young Earth some 4.5 billion years ago — not long after the birth of the solar system — but its rocks are much older than those typically found on Earth. 

The reason? The moon’s surface is relatively preserved, while Earth’s surface is continually recycled.

Earth’s tectonic plates subduct older crust down into the mantle and raise new crust to the surface, as well as cause lava to spew. Rocks from away from fault lines and volcanoes are not spared either, being eroded by everything from rain to glaciers. 

The moon doesn’t have any shifting plate tectonics or weather. Its most recent volcanic activity is thought to have occurred over 100 million years ago.  

“Earth is like a person who reinvents themselves, changes their name and moves to a new city,” Gregg said. “If we want to know about Earth's infancy and childhood, we have to look at the moon.”

Moon rocks may look good for their advanced age due to the lack of erosion, but they’re hiding internal fractures. The moon’s lack of atmosphere means constant bombardment from asteroids that melt the surrounding surface on impact, creating a glass that essentially glues the rocks’ fractures together.

Graduate students in the Geohazards, Volcanology and Geodynamics seminar got a view of this and other phenomena by placing the rocks under a microscope. They come sliced into thin sections to allow for light to pass through them and enhance the vibrant colors of their minerals.

One of the samples students examined was the famed orange soil collected during the final Apollo mission in 1972. The transmitted light revealed an array of orange glass spheres, the result of small droplets of molten rock that cooled rapidly.

“Why do you think they’re perfectly round, as opposed to on Earth where droplets come in all kinds of weird shapes?” Gregg asked the students.

“Because there’s no atmosphere on the moon,” one student answered.

“That’s right. There’s no atmosphere to deform those lava droplets once they’ve been ejected from a volcano,” Gregg said. 

Huggins is investigating the moon’s volcanic history as part of her master’s thesis. She created a geologic map of Gruithuisen Delta, one of three volcanic domes that comprise the moon’s Gruithuisen Domes. 

These domes are a geological enigma. They appear to have been created by silica-rich magma, which scientists didn’t believe could form without water and plate tectonics. NASA will send a rover to analyze the domes in 2028 as part of the Lunar-VISE mission.

“One big lesson I’ve learned during the course of my research is that scale matters, and it’s important to examine materials at different scales,” Huggins said. “So while these samples in class were not from the Gruithuisen Domes themselves, being able to examine the thin sections from various locations on the moon is incredibly helpful.”

The new lunar missions should bring back a wider variety of rocks. The Apollo missions were limited to landing in equatorial regions to ensure communication with Earth, but more satellites mean the Artemis III mission planned for 2027 can land near the moon’s South Pole. 

“What geology questions can be answered really depends on where precisely you’re going to land,” Gregg said. “So it’s an active area of research to determine the best place to land to get the most bang for your buck.”

For now, students can simply marvel at the kaleidoscope-like images provided by the rocks collected from Apollo. A mineral-infused breccia resulted in a striking image under the microscope, as colorful minerals contrasted against the darkness of the basalt. 

One student couldn’t help but comment on the image’s pareidolic nature.

“It looks like the solar system,” they said. 

“Well, parts of the solar system are contained,” Gregg replied.