It Fell on Our Heads from Space


 

It Fell on Our Heads from Space

“I have heard the stories about quasicrystals my entire life,” said Paul’s son, Will Steinhardt. Tall and slender, with what friends describe as an adventurous demeanor and quick wit, Will Steinhardt grew from a boy to a young man over the course of his father’s search. “A lot of people treated my father as this renowned scientist. But to me he was just my dad—and one of his interests was looking for this weird kind of crystal.” Still, something must have made an impression; Will Steinhardt eventually chose to follow in his father’s footsteps and began attending Caltech in 2007, where he majored in geophysics (BS ’11). 

Will was 20 and a sophomore when 46407/G was found, and as the elder Steinhardt undertook his investigation, the father and son would spend long hours discussing the rock together by phone and over holiday visits. “I think my dad would readily admit that he’s not a geologist,” said Will Steinhardt. “Here I was being educated at what I believe is the best geosciences program in the world.”

The two agreed that Caltech might be able to help more directly, and Paul Steinhardt brought the sample to Pasadena for testing, where he was referred to John Eiler, the Robert P. Sharp Professor of Geology and Professor of Geochemistry. Testing the samples at the Caltech Microanalysis Center, Eiler found silicates and oxides that bore a distinctive oxygen-isotope fingerprint dating back to the pre-solar system. The sample was extraterrestrial. 

“No mineral on Earth bears such a signature,” Eiler said. “There was your answer, and it was the least likely one: This rock fell on our heads from space.”

Now Paul Steinhardt had two important pieces of evidence: He knew that the rock was a fragment of a meteorite, and he also knew where it was found. There was one thing left to do. He called his son and asked if he wanted to join an expedition to Russia.

“There aren’t too many times you get to go to a remote part of the planet in search of a one-of-a-kind meteorite,” laughed Will Steinhardt. “You know…just a typical camping trip with your dad.”

 

Journey to the Source

In July 2011, a team of scientists, including Paul and Will Steinhardt and Bindi, gathered outside Anadyr, a town in the northeast of Siberia. There they met Kryachko and a small contingent of Russian mineralogists who would be their guides. Never an outdoorsman, Steinhardt was now venturing into one of the most remote regions in Russia. Weather ruled out traveling by air, so they would have to drive in snowcat trucks, which were essentially large metal boxes with tank treads meant to carve their own roads.

Crossing the tundra was a grueling four-day journey. The ground, packed under snow and ice for most of the year, had thawed to a slushy mud that made walking impossible. Bears were known to be close by, migrating to the streams for the wild salmon, which were so abundant you could reach in and catch them with your hands. Then there were the swarms of mosquitoes, which immediately attacked any exposed skin. “You would unzip your hood to eat, and they would fly inside your mouth,” Will Steinhardt said.

Kryachko led them to the small streambed where, 32 years before, he had first sifted the soil. They had finally arrived at the source.

Paul Steinhardt surveyed the area. He tried to remain realistic about their chances of finding another quasicrystal sample, which he estimated to be one in 1,000. The more feasible objective, he reminded everyone, was to learn as much as they could about the surrounding environment. Still—he allowed himself a bit of optimism. Over the next 10 days, the team worked to dredge mud from the river. The thick blue clay broke their shovels, so Will Steinhardt resorted to using his hands to fill 40-pound buckets, which they would boil down. Kryachko then panned the remnants in the riverbed and boiled it again, exactly as he had before, until all that remained was a thimbleful of dust. Will Steinhardt marveled at Kryachko’s speed and dexterity, “You could see the decades of experience in his hands.” 

 
EVERYONE PLACED BETS on whether or not they had found even one sample containing a quasicrystal. “By the time we left, I thought our odds had improved to one in 100,” Paul Steinhardt said.

Bindi examined some of the samples through a microscope in his tent. The more he looked, the more enthusiastic he became. “There were a number of samples that looked very similar to ours in Florence,” Bindi said. There was, of course, no way to know whether or not they had a quasicrystal until they returned—but Bindi’s optimism was infectious, and the team felt buoyed by the sense that they were on to something. 

Paul Steinhardt found that he could now relax a bit, which allowed him to appreciate another unique part of the experience—working with his son as a scientist. “One of the great privileges of being a father is the ability to form a relationship with your child as an adult,” Steinhardt said. “I got to see how excellent a field scientist Will is.” 

Will Steinhardt echoed the sentiment, “I came not just because I know geoscience, obviously, but also because I know my father. And after this trip…I felt I knew him better.”

Their last night, Kryachko offered a heartfelt toast, remarking that being associated with the search was a highlight of his career. Bindi felt the same, “This project has really become a part of me. I owe a great deal to my collaboration with Paul, and am proud to count him as a terrific friend.” 

Everyone then placed bets on whether or not they had found even one sample containing a quasicrystal. “By the time we left, I thought our odds had improved to one in 100,” Paul Steinhardt said. Bindi wagered one in 20.

 

Beating the Odds

Bindi was right to be optimistic. Back in Princeton, tests conducted on one of the larger samples revealed the same composition of aluminum alloy and—lurking within—a grain of quasicrystal, the very same variety that had been found in 46407/G. 

“All of that crazy, crazy stuff we went through—it just paid off,” Paul Steinhardt said. “To see that exact same X-ray diffraction pattern was immensely satisfying.”

While Steinhardt and Bindi were conducting their research, Dan Shechtman was awarded the Nobel Prize in Chemistry for spotting the first quasicrystal nearly three decades earlier. The quasicrystal had gone from a theoretical object, to a contested curiosity, to an accepted man-made substance, to—when Steinhardt and Bindi published their full findings in the spring of 2012—a part of nature. 

There are, it turns out, a number of mysteries packed into the tiny specks of Paul Steinhardt and Bindi’s extraterrestrial rock: Not only the presence of never-before-seen combinations of elements like metallic aluminum, but how they formed and what that tells us about the evolution of our solar system. 

“We thought that a certain type of matter could not exist—and it can. Then we thought nature couldn’t make it—and it does,” Paul Steinhart said. “The existence of this one little rock tells us that we missed something, which raises the question: What else might we be missing?” Like any good mystery, the story continues, but the investigators have assembled a compelling case for the journey of 46407/G:

Four-and-a-half billion years ago, objects in the pre-solar system smashed together, resulting in an object with strange and unusual properties, including particles of quasicrystal. The asteroid lingered in space until 15,000 years ago, when it fell to Earth, crashing into the mountains of what would eventually be northeastern Russia. With time and erosion, the shattered pieces slowly migrated, coming to rest in a small streambed, where they were sifted in 1979 by a young Russian mineralogist panning for gold. One piece was sent to a museum in St. Petersburg, the other passed through several hands before coming to the University of Florence, where it was labeled and placed into storage. Decades later, a researcher spotted signs of a dazzling crystalline structure lurking inside, and sent it to Paul Steinhardt, the man who was among the first to imagine that such a crystal could even exist, and who had been searching the world for just such a rock.

What would be the chances? Incredibly low. But not, it turns out, impossible.