The Second Kind of Impossible

by Paul Steinhardt

  John worked closely with Yunbin Guan, the director of Caltech’s Microanalysis Center. The Center had a valuable piece of equipment called a NanoSIMS, a nanometer-scale secondary ion mass spectrometer, which could perform the oxygen isotope test that Ed Stolper had recommended. There are only a handful of NanoSIMS in the world, and only a few institutions, including Caltech, allow outsiders to collaborate on projects.

  John had agreed to use the NanoSIMS to perform the oxygen-isotope test on one of our tiny grains. I flew to Pasadena to meet with him, carrying our tiny grains in a small sealed box carefully tucked in my book bag. There was no way that precious box was going to be put in checked luggage.

  Once I arrived at Caltech, John and I spent several hours reviewing all the measurements made by our team in our three labs: Princeton University, the University of Florence, and the Smithsonian Museum of Natural History. It was the same set of data I had shown Ed two months earlier, coupled with our recent discovery of stishovite.

  Like Ed, John concluded that the likely origin of our sample was terrestrial. “Aspects of the olivine mineral grains remind me of terrestrial samples I have studied,” he said. Although my inclination was that our sample came from outer space, I greatly respected Ed and John’s opinions and kept an open mind.

  I was truly delighted that John was eager to help. He was smart, energetic, and precise. But I was deeply disappointed by what he told me next. The NanoSIMS was a mercurial piece of equipment and was currently under repair. It would probably be a few months before it would be back in working order.

  Luca and I had no choice but to wait. The next few months proved to be agonizing. Every day Luca and I had a Skype exchange during which we debated the possible outcome. Inner space or outer space? Outer space or inner space? But what if the test was inconsistent with either a terrestrial or an extraterrestrial origin? Then, despite all our precautions, we would have to consider the dreadful third possibility. Malicious mischief.

  The NanoSIMS is an unforgiving test that can unmask a fake material in a heartbeat by measuring the distribution of nuclear isotopes in the sample. This was a feature that a hoaxer would not have anticipated and could not have faked. The longer we had to wait for the test, the harder it was to get this depressing possibility out of our mind.

  * * *

  PASADENA, JULY 2010: Two months later, we were told that the NanoSIMS was finally back in working order and our sample would be tested sometime during the last ten days of the month. Every few days, I would check to see if the test had been performed. “Not yet” was always the reply. The excruciating wait continued.

  The NanoSIMS was an ideal instrument to study the isotopes of oxygen atoms in our sample. Atoms are distinguished from one another by the number of protons. For example, all oxygen atoms have 8 protons, which is why it is listed as the eighth element in the Periodic Table. The term “isotope” refers to atoms with the same number of protons, but with different numbers of neutrons.

  There are three stable types of oxygen isotopes, each with 8 protons but different numbers of neutrons. The most common type of oxygen atom has a matching number of protons and neutrons: 8 protons and 8 neutrons. Since 8 + 8 = 16, this isotope is labeled 16O. But there are two less common oxygen isotopes. 17O has 9 neutrons. 18O has 10 neutrons.

  If you were to study all of the oxygen atoms in the air you breathe, you would find that 99.76 percent of them are 16O, 0.04 percent of them are 17O, and 0.2 percent of them are 18O.

  The relative percentages on Earth are determined by the history of the planet and the exposure of its minerals to cosmic rays and radioactivity. Other planets, like Mars, have had different evolutionary histories and their minerals have been exposed to different levels of cosmic rays and radioactivity. So minerals from Mars contain percentages of the three oxygen isotopes that are different from those found on Earth. The same applies for minerals formed on other planets and on different types of asteroids.

  By using a NanoSIMS to measure the amounts of the three oxygen isotopes in different minerals in a sample, a geochemist can determine if the sample is natural and, if so, where it came from.

  * * *

  PASADENA AND PRINCETON, JULY 26, 2010: At last, the long-awaited email arrived from John Eiler announcing that the NanoSIMS measurement had been performed and the results analyzed:

  The two important findings are: the 17O anomaly is significantly less than 0; and the 18O is very low.

  I felt like screaming out of sheer frustration because, after all these months of waiting, I had no idea what that sentence signified. It was geochemist-speak, and I am not a geochemist. As I continued reading, I was happy to discover that John had translated the findings into a language that I could understand, using a plot similar to the one on the next page to illustrate his point.

  The horizontal axis of the graph represents the amount of the rare isotope 18O found in the sample compared to the most common isotope 16O, which is known as the 18O anomaly. The vertical axis represents the amount of the rare isotope 17O compared to the most common isotope 16O, which is known as the 17O anomaly.

  Also shown are two grayish lines that meet toward the upper right. The two lines cross at a point that roughly corresponds to levels one would measure in ocean water on the Earth. The upper line labeled TF refers to Terrestrial Fractionation, and indicates what fractions of 17O and 18O are found in various kinds of minerals that formed on the Earth. Because rocks on Earth form in different ways, they do not have exactly the same isotope distribution as ocean water, but rather, can take any of the values along the TF line.

  The circles, diamonds, squares, and triangles with lines sticking out represent the values measured for different types of minerals found in the Florence khatyrkite sample: pyroxene, forsteritic olivine, nepheline, and spinel. They do not lie along the line labeled TF, terrestrial fractionation, which indicated that the Florence sample did not originate anywhere on our planet.

  Equally important, the results were not randomly distributed, as they might have been if the material was an intentional hoax or had been accidentally synthesized in a laboratory or aluminum foundry. Instead, all the data aligned along a different line labeled CCAM.

  CCAM is the acronym for Carbonaceous Chondrite Anhydrous Mineral, a technical term for a stunning conclusion. It was the geochemist’s way of saying that the Florence sample, including our quasicrystal, was definitely an extraterrestrial. A visitor from outer space. A meteorite.

  More specifically, a CCAM is a rare type of meteorite called a “CV3 carbonaceous chondrite.”

  Luca and I were all too familiar with CV3 carbonaceous chondrites, especially the most famous one called Allende. The Allende meteorite had nearly derailed our project.

  One year earlier, Glenn had concluded that the powdery material in the vial marked 4061-Khatyrkite from Curzio Cipriani’s home laboratory was actually from the Allende meteorite. He had memorably ascribed the mix-up to a “capricious, if not overtly malicious, God.” From that, he had gone on to conclude that Cipriani was careless and the mineral collection from Florence untrustworthy. The fallout nearly prevented the initial public announcement of our discovery of a natural quasicrystal.

  As a result of the NanoSIMS test, Luca and I now knew that Glenn was wrong to identify the material as Allende. But there was a perfectly good reason for his error. The Florence khatyrkite sample was exactly the same type of rare meteorite. Both were created 4.5 billion years ago at the beginning of the solar system under similar conditions and contained many of the same minerals. No wonder Glenn had mistaken one for the other.

  But they were not an exact match. The Florence sample was even more intriguing than Allende because it contained aluminum-copper metal alloys that had never been seen before in any other known rock or mineral. Therefore, it was arguably more important than Allende, because it contained evidence of physical processes in outer space that had been previously unknown. Those processes might have affected the evolution of planets and the
earliest stages of our solar system. But how so?

  Luca and I knew where to go for the answer. Right back to one of the world’s foremost experts on CV3 carbonaceous chondrites: Glenn MacPherson. Glenn had been criticizing our work for the last year and a half. He was the strongest advocate for the theory that the Florence sample was a worthless piece of slag. From the very moment he and I had first laid eyes on each other on the steps in front of the Smithsonian Natural History Museum, Glenn had been explaining to me why, in his expert opinion, the sample could not possibly be a meteorite.

  The original images recovered from Luca’s damaged hard drive had only indicated a jumbled mess of a dog’s breakfast, as far as Glenn was concerned. Neither the Amsterdam detective story that led to a connection with the St. Petersburg holotype nor our eventual contact with Valery Kryachko, who had originally recovered the material from a Kamchatka dig site, had seriously altered his view. Glenn even managed to retain some degree of skepticism after Luca discovered stishovite enclosing a slug of quasicrystal in the sample.

  The NanoSIMS test could have invalidated all of our hard work and proven Glenn’s skepticism to be well-founded. Instead, it produced the opposite result. It instantly confirmed our original hypothesis that the Florence sample was natural.

  To Glenn’s credit, it also eliminated every last fiber of resistance. Always known for a clever turn of phrase, Glenn’s email response after receiving my report of the NanoSIMS results began with a simple subject line: “Welcome to my world.”

  First, congratulations—you have an extraterrestrial sample. I work with oxygen isotopes all the time, so I understand the diagram extremely well and what it implies. . . . This new data changes everything. You can call off your expedition to Siberia for one thing, and you can stop worrying/thinking about things like ultrahigh pressures and lower mantle and serpentinization and all that other stuff. . . .

  But now we have several new mysteries. If this thing really did come out of a sediment deposit and it really is a meteorite, I don’t know how they found it and I don’t know how it survived. . . .

  This whole project is now suddenly and squarely in my realm, which means that I will have to take a more central role in guiding it. Welcome to my world.

  Convincing Glenn was a major milestone. Luca and I had enormous respect for his expertise and his intellectual honesty. Lincoln Hollister was also delighted to learn of Glenn’s reaction. Both members of the red team happily conceded to the blue. We were now unanimous.

  Luca and I could not help but be amused, though, with Glenn’s sudden claim of ownership. Of course, we had absolutely no intention of giving up our leadership roles.

  * * *

  PRINCETON AND FLORENCE, OCTOBER 1, 2010: Two months after the confirmation from Caltech’s NanoSIMS test, Luca sent me even more good news.

  The International Mineralogical Association Commission on New Minerals, Nomenclature and Classification had just voted to accept our quasicrystal as a natural mineral. They also accepted our proposed name: “icosahedrite,” a fitting name for the first known mineral with icosahedral symmetry to be entered into the official catalog.

  I savored the historic moment. This was one of the milestones I had been seeking since first imagining the possibility of natural quasicrystals. But I knew the story was not yet over. I went back to reread Glenn’s message in which he wrote,

  You can call off your expedition to Siberia for one thing . . .

  I stared at the note and shook my head. He’s definitely wrong, I thought.

  There was now convincing evidence that our sample was a visitor from outer space and most likely a creation dating back to the birth of the solar system. But many mysteries remained. How did it first form? Why did it contain quasicrystals? What path did it take through space before entering the Earth’s atmosphere? How did pieces of it become lodged in the blue-green clay of the Listvenitovyi? And why had it not corroded since its arrival on Earth?

  The few remaining specks of the Florence sample were not enough to answer any of these questions. We needed to recover more material from the same source. The only way to resolve the remaining mysteries was to charge ahead with an expedition to Kamchatka in search of more specimens. That was absolutely clear in my mind.

  What I never envisioned, though, was that I might be forced to take part in such an adventure.

  PART III

  * * *

  KAMCHATKA OR BUST

  SEVENTEEN

  * * *

  LOST

  MIDDLE OF NOWHERE, KAMCHATKA PENINSULA, JULY 22, 2011: Somehow the unimaginable had happened. No one was less suited to take part in, much less lead, an expedition to the remote regions of Far Eastern Russia. Yet here I was.

  For the last sixteen hours, I had been riding aboard a giant tracked vehicle that was carrying me, along with half of my team, across the desolate tundra of the northern Kamchatka Peninsula. At last, close to midnight, we rumbled down a steep hill and stopped for the night by a riverbed. I felt calm and settled despite the strange and unfamiliar surroundings.

  That equilibrium was shattered the moment I climbed out of the cab and leapt off the huge tractor treads to the ground below. Suddenly I was suffocating. Sensing my breath, hordes of mosquitoes had sprung out of the muck and formed a thick cloud around my head, effectively cutting off my air supply.

  I was desperate and embarrassed at the same time. Desperate to breathe, and embarrassed to display any vulnerability because I was the supposed leader of this expedition. I tried to hide my distress from the rest of the team by slowly edging away toward the hill behind us, all the while futilely attempting to bat away my attackers.

  Desperate to regain my composure, I forced myself to focus on the series of events that had somehow convinced me to travel thousands of miles to this hellish, forsaken, mosquito-infested place.

  I was originally suckered into the trip by the discovery of a natural quasicrystal in an unremarkable mineral sample that had been hidden for years in the storage room of an Italian museum. Through extraordinary detective work, we had proven that the sample was part of an ancient meteor dating back 4.5 billion years to a time before the birth of the solar system. Our extraterrestrial had survived numerous interstellar encounters and collisions while hurtling through space at nearly 100,000 miles per hour. It finally entered the Earth’s atmosphere about seven thousand years ago, around the same time human beings were inventing the wheel. The meteor announced its arrival by heating to a spectacular incandescence, streaking across the sky just south of the Arctic Circle before landing in the Koryak mountain range in the Kamchatka Peninsula where it remained undisturbed for thousands of years.

  In 1979, a young Russian student named Valery Kryachko was hired to search for platinum along a stream bed in the middle of the Koryaks and accidentally found a piece of our extraterrestrial buried in layers of a mysterious blue-green clay. From there, the unrecognized sample began a thirty-year journey which eventually brought it to our laboratories, where we discovered natural quasicrystals embedded inside.

  Now, several years after that discovery, we were returning to Kamchatka with that same Russian student, now sixty-two years old, in search of more pieces of the meteorite.

  We knew the Florence museum sample was controversial. The weird chemical compositions of the quasicrystals and some of the metallic crystal alloys we identified contradicted scientific principles about what forms of matter could exist in nature. So in spite of all the evidence we had gathered, a few scientists continued to question whether the sample was natural at all.

  We had been chipping away at the Florence sample for the past two years on two continents, performing every test imaginable to learn the secret behind the never-before-seen minerals. We had conducted so many tests, in fact, that we had managed to destroy all of the sample and had nothing left to study. The only way to advance the science was to travel to Kamchatka and find more material.

  Having come this close to proving natural quasicry
stals exist, I had no choice. I was absolutely compelled to go Kamchatka! Wasn’t I?

  Although I was still suffocating, barely squeezing in quick breaths of air while swatting away at the insect swarm, these inner thoughts began to calm me down.

  And then, a tsunami of panic swept over me as a truly terrifying thought came to mind. The second vehicle carrying the other half our team—including my youngest son Will—was missing.

  The two vehicles had been traveling together most of the day, but Will’s truck had been limping along because of mechanical problems and had slipped out of sight a few hours earlier. Our driver had assumed it was trailing just beyond our view. But if that were the case, it should have caught up with us by now.

  Standing alone at the top of the hill in Kamchatka with my stomach in knots and my mind reeling, desperate for any sign of Will and the rest of my team, I felt an overwhelming sense of guilt. I had challenged the impossible once too often with the horrifying result of having put my own son’s life in danger and perhaps losing half of my team.

  One by one, I had blown past explicit warnings from all kinds of experts: Searching for new samples is hopeless. A trip to such a remote region is not worth the risk. The expedition will never be fundable. Pulling together a team in just a few months is unachievable. You took a wrong turn in this investigation. It’s foolhardy for someone like you to make this trip. That expedition site is inaccessible.