This column first ran in The Tablet in April 2017
We believe in things we cannot see – God, say, or Black Holes – because we observe their effects on the things that we can see. Still, there is a little bit of Doubting Thomas in all of us. It would certainly be nice to have a direct image of what a black hole actually looks like!
The Event Horizon Telescope (EHT) is designed to do just that. It isn’t one instrument, but a collection of radio telescopes spread around world, observing the same object at the same time. Using a technique called Very Long Baseline Interferometry (VLBI), which compares the very tiny differences between different telescopes’ signals, a high resolution picture emerges. The farther apart the telescopes are, the better the image’s resolution; the EHT telescopes span the width of Earth itself.
After nearly 25 years assembling the team of telescopes and refining the technique, this month the EHT began its first concerted observations of the black hole at the center of our galaxy. We can’t see the black hole itself, of course; light can’t escape from its massive gravity. But a black hole’s size and shape can be measured by the shadow it casts against the radiation emitted when material falls into the hole.
Chair of the science council for the EHT is Heino Falke, an astronomer at Radboud University (where I spoke in December, 2016, at his invitation). I first met Heino in 1993 when we were students together at the Vatican Observatory’s Summer School (VOSS). This week I sent him an email to ask about the EHT.
“I first developed the idea in 1993, while I was at the VOSS,” he wrote me. His thesis advisor, Peter Biermann, was a VOSS lecturer; they eventually worked out how one could use VLBI to detect the shadow of a black hole. Subsequent visits to Arizona, including using the Sub Millimeter Telescope (next door to the Vatican’s telescope on Mt. Graham), ultimately led him to the EHT project.
Sub-millimeter radio waves are just right to resolve the shape of the black hole’s shadow. There is plenty of radiation emitted in these wavelengths from the “Event Horizon,” the last point where light can escape the black hole’s gravity. The black hole’s shadow should be visible against the scattering of these radio waves. And Earth is just big enough that comparing signals from opposite hemispheres can resolve the magnified shadow. (It helps that the shadow is magnified by the black hole’s gravity itself.) Heino pointed out, “those three effects are completely unrelated. So, that is truly fine tuning of the universe… Thank God!”
The goal of the experiment is to test if the shadow’s size and shape matches what General Relativity predicts: between 45 (if it is rotating rapidly) and 52 (non-rotating) micro-arc-seconds (about the size a DVD on the Moon would look to us on Earth). The shape of the shadow should tell us how fast it is spinning.
A parallel project hopes to measure pulsars in the Galactic Center. “That would help us to get even better combined constraints of the nature of space-time, like the quadrupole moment, which in General Relativity is uniquely determined by mass and spin,” Heino explained. Black holes don’t show these higher order details; as Heino puts it, “black holes are the simplest objects in the universe.” So far, only one observable pulsar has been found, but he remains hopeful.
Want to know more? “Ah, ja, also Ray Jayawardhana wrote this nice article in The Atlantic recently about the EHT and my work,” Heino told me. “We were at the same VOSS, of course.”
Guy Consolmagno SJ is the director of the Vatican Observatory.
Sometimes I write columns and then decide not to submit them to The Tablet. This was my alternate column for April 2016; this is the first time it's been published. Comments?
The Vatican Observatory exists to show the world how the Church supports astronomy, and so a large part of my work is traveling the world to talk about our work. Two recent  stops have been particular eye-openers to me.
Brigham Young University in Provo, Utah, just outside Salt Lake City, is the premier center of learning for the Mormon Church. For reasons that still puzzle me, I was invited to be the first non-Mormon scientist to give their annual Summerhays Lecture on Science and Religion.
They went remarkably out of their way to make me feel at home. Indeed, the university guest house even caters to its gentile guests by having a coffee machine — the only coffee allowed on campus. (Stimulants like caffeine are forbidden to Mormons, though they’ve decided that cola-based sodas are exempt.) A planetary scientist colleague of mine there, herself an active Mormon, invited me to her class and organized a seminar for me to talk about my research. I was even taken up to the famous Sundance Ski Resort for an afternoon of snowshoeing. (They’d offered to show me the historical and religious sites of Salt Lake City. I pointed out that, as I live in Rome, hiking their glorious mountains would be more of a treat.)
Meanwhile, a retired chemistry professor (a Catholic married to a Mormon), was my local guide to the oddities of Mormon theology. I had devised a talk that I thought would be non-controversial, examining how we “people of The Book” — Christians, Jews, and Muslims — are free to study nature with science because we reject nature gods: our God is supernatural. But the more I learned of Mormon beliefs, the less clear it was such an assumption about how they view God actually fits their unusual theology.
A month later, I was at a small school set in the rolling hills of my home state of Michigan, a liberal arts university where a third of the students are active Catholics. Hillsdale College is famous for proudly refusing to accept any government money. The sticking point, according to a document that they included in their welcome packet, is how the Government (specifically naming “the Obama Administration”) demands to know the racial makeup of their student population. This is insulting to a college like Hillsdale, which since its founding before the American Civil War has proudly proclaimed that it accepts students of any race or creed. Indeed, Hillsdale sent a record number of graduates to fight for the Union in that war; those veterans are commemorated in a prominent statue on campus. More recent statues honor Winston Churchill, Ronald Reagan, and Margaret Thatcher.
Indeed, it is hard to imagine that any black student ever encounters prejudice at Hillsdale; in my two days there, I never saw a single black student — or teacher. (I am told they have a few scholarship students from Africa.) When I asked if they had any Jewish faculty, I was told, “he’s retired.” At least they did serve coffee.
I feel churlish commenting about these places. In both schools, the hospitality was genuine and the students were wonderful. Both schools have active astronomers doing first-class work. But in both places, I felt uncomfortably out of place. I realize now that it’s probably how my non-Catholic friends must feel when they visit me at the Vatican Observatory.
The glorious thing, however, is that even though our politics or theology may be very different, we are all nonetheless united by our love of astronomy.
We all live under the same stars. The heavens proclaim the glory of God to everyone.
This column first ran in The Tablet in April 2016; this has been slightly edited.
Planet Nine, whose possible existence was first broached in January 2016, has become a hot topic of speculation. By April of that year, one tabloid announced that comets perturbed by Planet Nine would soon lead to the demise of life on Earth! (Astronomer Phil Plait ran an amusing rebuttal in The New Scientist.) But, is there actually a Planet Nine?
Recall, an Astronomical Unit (AU) is the distance from Earth to the sun. From the sun to Neptune, the farthest known planet, is 30 AU. Pluto is but one of a thousand balls of ice orbiting between 30 to 50 AU.
But in 2003, Mike Brown and his team at Cal Tech found a body they named Sedna whose orbit comes no closer to the Sun than 76 AU, and which actually arcs out to nearly 1000 AU. It’s hard to imagine how it could have been formed out there; more likely it was pushed there by the gravity of some other planetoid.
Now, there are two ironclad rules of celestial mechanics that apply here. First, any two bodies perturb each other with equal force, with the bigger change occurring to the smaller body; so the perturbing body has to be a lot bigger than Sedna to cause its wild orbit. And these two bodies must pass close to each other for their gravities to have an effect. If Sedna was perturbed by a bigger body, then that bigger body must also be out there orbiting where Sedna orbits.
That much was known in 2003. But by early this year, Brown had found five other bodies in huge orbits just like Sedna’s. Konstantin Batygin, a celestial mechanics whiz with a fast computer who works with Brown at CalTech, calculated that one and the same large body (they guess about ten times the mass of Earth) orbiting from 200 AU to more than 500 AU from the sun could be responsible for all of those wildly perturbed orbits.
If there is such a body, why haven’t we seen it? It must be faint and far away. It could well be orbiting now in a part of the sky we’ve never searched. Indeed, it might be sitting right in front (from our point of view) of the densest part of the Milky Way, its faint light hidden among a million other equally faint dots.
When I was a student, the idea of something ten times bigger than Earth orbiting out so far from our sun would have been laughed at. No rocky planet could be so big, or so distant. But now we’ve discovered systems of planets orbiting other stars, and from them we have learned that ten-times-Earth is a pretty typical size for planets. Furthermore, we’ve seen that such planets can indeed change their orbits by such great amounts, early in the histories of their solar systems.
In fact, we now think that Uranus and Neptune themselves were actually formed close to Saturn and then flung out to their current locations during the early history of our own solar system… maybe at the same time that smaller chunks rained inwards, peppering the Moon with its craters and covering the Earth with water and carbon-bearing ices. There’s plenty of room in our theories for another planet, say a big chunk of rock and ice, to be sent out to where Planet Nine is proposed to exist.
And notice a sweet theological echo to this proposal. We can’t see Planet Nine; not yet. But still, some believe it exists; because they can see the things that it has done, to the things that we all can see.
Note added in 2018: This hypothesized planet is still controversial... and not yet found. See a recent article about it here in the Atlantic...
Horst Rademacher, a seismologist at U C Berkeley, wrote to friends of mine there last weekend, asking about the date of Easter:
Tomorrow (Apr 1) is Easter. According to the classic definition Easter always falls on the first Sunday after the first full moon after the vernal equinox. That makes sense, because today is full moon, which is the first full moon after the beginning of spring. And tomorrow is Sunday, hence Easter.
However, today's full moon occurred at 5:37 am PDT. Let's assume, the full moon would have occurred at 5:37 pm PDT. Applying the definition above from a purely California perspective, tomorrow would still be Easter. However, if we were in the Netherlands, in Germany or in the Vatican for that matter, this assumed full moon would occur the next day at 2:37 CEDT. But because the next day (tomorrow) is a Sunday, it could not be be Easter, because Easter always falls on the first Sunday AFTER the first full moon. Hence Easter would fall on the next Sunday......
So here is the question: Do you know in which time zone the full moon is measured in order to define Easter? If you don't know, does your friend, the astronomer in the Vatican know?
Sorry to bother you with something that esoteric...
The short answer is this: in the Gregorian calendar, Easter is no longer defined as the first Sunday after the first full Moon of spring. Instead, it is determined by a totally arbitrary formula that approximates this definition, getting it right for most but not all of the years in the 19 year Metonic lunar cycle.
Originally published in The Tablet in March, 2008, and again here in 2015. Slightly edited.
A few years ago while I was showing friends around the Vatican Observatory in Castel Gandolfo, we bumped into a couple of visiting astronomers from Poland. After making the appropriate introductions, I mentioned that Jozef Zycinski also happened to be the archbishop of Lublin. My friends were suitably impressed; an astronomer/archbishop is something most people don’t see every day. But his companion in the hallway, Michael Heller; how could I describe him? As of 2008 I could also say, “he’s the winner of the 2008 Templeton Prize.”
I first met Michael Heller in the early 1990s. Chatting over breakfast in a Tucson diner, I innocently asked him what sort of astronomy he did. He explained that he was interested in finding a mathematical framework that could unite quantum theory with Einstein’s Theory of Relativity. Then he launched into the details of “a noncommutative algebra from which a differential geometry can be constructed...” Even though I was fresh from postgraduate courses in cosmology at the University of Chicago, I was lost. Those courses had been just enough to let me recognize that I was way out of my league.
It turns out that his theology and philosophy are at an equally high level, and equally difficult for the layperson to understand. I asked Bill Stoeger, the resident cosmologist and theologian among my fellow Jesuits at the Observatory, if he could give me a short summary of Heller’s “big ideas.” In a word: no. Indeed, a few years ago his fellow philosopher Stanislaw Wszolek wrote a paper on Heller’s work that ultimately summarized it by merely saying it rejects “the popular simplifications and divisions which appear abundantly in philosophical course-books and popular science books.” The short answer is that there is no short answer.
Instead of all that scholarship, I have a more familiar picture of Michael Heller. Stories at the Vatican Observatory describe how in the 1980’s he would escape to Castel Gandolfo, staying with us while he visited with his fellow Polish academic and close friend in whose summer home we lived. (Heller contributed significantly to Pope John Paul II’s documents supporting science in the Church.) When Michael came, our rector knew to stock up on bananas: rare delicacies in Poland during those last dark days of Communism.
And I remember my own visit to Cracow at Michael’s invitation in 2000, where he did an impromptu simultaneous translation into Polish of my talk. Half the audience got my jokes in English, the other half laughed at his Polish versions; he must have done them justice.
But can justice be done to a scholar like Michael Heller? Can the rest of us ever appreciate Heller’s contribution to the interface of science, mathematics, theology, and philosophy… especially when most of the popular attention nowadays gets focused on those whose expertise in one field is paired with an embarrassing naïvety in all the others? Indeed, his enormous talents are at such a high level, can they ever really connect to the rest of us?
It’s an issue that haunts every academic working in a rarefied field.
At the end of the day our life’s work is nothing but a pile of equations and words, mere wind, whose ultimate value (if any) we may never live to see. And, like St. Aquinas, we can recognize that a sudden insight into the face of God can make all our work look like straw best suited for the fire. Yet, like St. Aquinas, our poor writings can change the course of human thought, even to inspiring some future Michael Heller.
In the meanwhile, we find our encouragement in the joy of the work itself, which reflects the joy of the Creator… supplemented, of course, by the affirmation of the occasional million dollar prize.
Originally published in The Tablet in March, 2007, and again here in 2015... this version is slightly edited.
The late Stephen Jay Gould, Harvard biologist and popular science writer, once described the roles of science and religion as “non-overlapping magisteria” – they should not be in conflict because they never come in contact. I could see his point; as cases from Galileo to Dawkins have shown, authority in one field rarely translates into authority in the other.
But as those same cases also demonstrate, science and religion do overlap all the time in at least one locus: in the human being, who chooses how to live in a world that has both science and religion. Indeed, the same is true of all the worlds each of us live in: our politics, school, favorite music, social background, sports teams, family. We all have our homes in each of those fields.
I felt caught up in such a web back in 2007 when a friend of mine (an Indian, from India) at the University of Wisconsin invited me to an Indian (Native American) reservation in northern Wisconsin, to join with other invited space scientists and Native Elders in presenting science and creation stories.
The whole concept of mingling “science” with “storytelling” would have had an earlier generation of scientists foaming with rage. Once, philosophers of science insisted that our work had a truth value superior to any other form of human knowledge because it was based on the pure reason of mathematics. They called themselves “logical positivists.” But ultimately their greatest accomplishment was to show that science itself was illogical: just because the light comes on when you flip the switch a hundred times in a row, doesn’t prove that it will work the hundred and first time. Science has to assume, without justification, that a repeated pattern is evidence of a deeper law, not just a string of coincidences. But sometimes it’s wrong.
A later generation of philosophers have pointed out how strongly science has been shaped by accidents of history and the personalities of who was doing the science. It really is a story, one that can be told around a campfire… or over a beer at a conference, late into the evening after the sessions are over.
Even the mathematics we use is a form of poetry: Newton’s equation for gravity provides a beautiful metaphor for the path of a falling rock. Like good poetry, it allows our human minds to see things in a new and deeper way. And it is judged by its elegance of form as well as its content of truth.
We choose the stories we tell for the truth we need to convey, and adapt those stories to the audience we’re speaking to. It’s the same truth, the same story teller, but a new story every time we tell it. That’s why we never tire of seeing Shakespeare performed; indeed, every performance, even of the same production by the same cast, is a new experience.
Thus we have the details of the solar nebula, the cloud of gas and dust from which the planets formed, described in very different ways by astrophysicists observing distant nebulae, and meteoriticists looking at rocks from the nebula that made our solar system.Thus we have two creation stories in Genesis in Chapters 1 and 2, which differ in the sorts of details that would drive literalists nuts if they actually were paying attention. Thus we have creation stories from other, non-European cultures, that still have a power to help us place ourselves in the universe. Someday we may even be able to trade creation stories with ETs.
To travel to this storytelling with Native American elders, I’ll be flying to a remote wilderness area in northern Wisconsin, far from the paths where I normally work. Oddly enough, though, a forty-five minute drive from there will bring me to my brother's house in Michigan. Some locations are closer to home than you might think.
Originally published in The Tablet in March, 2006, and republished here in 2015. This version is slightly edited.
The 2006 Lunar and Planetary Science Conference, held outside the Johnson Space Center in Houston, was unusually rich. We saw fiery dust from an ice-rich comet; startling images from Mars; a new type of lunar rock… and that was just on Monday morning. By Friday afternoon, I was exhausted.
I had already heard the Stardust results (see Across the Universe) at the Sunday welcome cocktail party when one of the mission scientists whispered to me, “We’ve found CAIs!” (Another friend on the team described Stardust Principle Scientist Don Brownlee’s first comment when they finally got the samples: “I can’t believe it actually worked!”)
These high-temperature grains of Calcium and Aluminum oxides that appear as Inclusions in certain meteorites are thought to represent the first solid materials to crystallize out from the hot gases that made the sun and planets. How did they wind up wrapped in comet ices, stored in the farthest reaches of our solar system? In fact, a controversial theory of the early Sun had predicted a powerful wind of plasma and magnetic fields that could have blown just such crystals outward, in streams above and below the disk of the planets. Suddenly this theory doesn’t look so unlikely.
On Wednesday, the team of the Cassini spacecraft mission to Saturn showed their images of its moon Enceladus spewing geysers of liquid water out of its south pole. Does this water represent a global ocean under the Enceladus crust? Should we be looking there for signs of life?
That afternoon, the Deep Impact team had their turn. Recall (Across the Universe) that the previous July they’d flung a copper canister at nearly 40,000 km/hr into the nucleus of Comet Tempel 1. Their high speed movie showed a “puff” of superheated rock droplets at the instant of impact, followed by a cloud of dust and ice. Spectrometers on board recorded the chemical composition of the cloud; and watching it fall back to the comet let them measure the comet’s weak gravity. It is so low that the comet nucleus must be quite fluffy, more than half empty space.
Friday morning, the Japanese Hayabusa mission (Across the Universe) presented their results. Their target asteroid, Itokawa, also appears to be a rubble pile, 40% empty space, covered with boulders and gravel. Their lander picked up samples, but trouble with the spacecraft means they may not get them back to Earth until 2010, three years later than planned.
Perhaps giddy with these delightful results, several scientists presented some more adventurous speculations. Jonathan Lunine (then at University of Arizona, now at Cornell), in a special prize lecture, suggested that we should send blimps to Titan (Across the Universe) to cruise its atmosphere, with occasional forays to the surface to look for life in its methane lakes.
Brett Gladmann (University of British Columbia) presented calculations showing that microbe-bearing meteorites launched by impacts from Earth could actually reach Titan. Would that provide the seeds of life for Jonathan’s blimps to find? “Don’t ask me,” Brett replied. “I’m just the pizza delivery boy.”
Not all was sunshine and fun. At a sober session Monday evening, the scientists heard the bad news that NASA is cutting their science budget by 15%, with Astrobiology (Across the Universe) chopped in half. Cost overruns with NASA’s shuttle, and the general dire state of the US budget, are to blame.
Indeed, the week before the meeting I had visited New Orleans, a city whose devastation was indescribable. There are no shortages of places that need our resources, both financial and human. But for one week, a thousand planetary scientists remembered that this universe of storms and human tragedy is also a place of surprise and delight; that the joy of discovery can give us the strength to face tragedy. It is evidence of God’s presence across the Universe.
[More than ten years later, our science has advanced but many things remain the same. New Orleans has recovered from its hurricane; Puerto Rico has not. Brett Gladmann is still saying witty things about asteroids. The NASA budget is, as ever, under attack. And the Lunar and Planetary Science meetings continue to be held every year in Houston though it is no longer held on the site of the Johnson Space Center. I went to my first one in 1976; it's been a while since I have had the chance to get back, lately, alas.]
Originally published in The Tablet in March, 2005, during the centennial year of Einstein, and the month when Pope John Paul II died. It also ran here on The Catholic Astronomer in 2015; it's slightly edited for 2018.
The intense but often erratic news coverage of the events in Rome following the death of Pope John Paul II could tempt one to despair at the state of journalism. With their talent for misstating the obvious, can we have any hope in entrusting to them the legacy of John Paul II, or the significance of his successor? Hope, however, can be found in an example from science, and how the popular press has served the reputation of another giant of the 20th century.
The year 2005 was the year of Einstein. In his honor, the UN declared 2005 to be the World Year of Physics. April 18, 2005, marked the 50th anniversary of his death; and it was exactly 100 years ago that year that in four famous papers he demonstrated the particulate nature of matter and light, and then revolutionized our sense of common sense by showing that time was equivalent to space, and energy equivalent to mass.
We have all grown up in a culture that has produced its own equivalence: the name “Einstein” equals genius, while genius implies shaggy white hair and a German accent. But how did that happen?
The biographies tell us when it happened. Einstein was a patent office clerk with a newly-minted PhD from Zurich when he submitted his famous four papers in 1905. Following their success, in 1908 he was a lecturer in Bern; a professor in Prague in 1911; and given a chair in Berlin in 1914. By 1915 he had worked out his General Theory of Relativity (a far more daunting, and revolutionary, result than the 1905 paper) and his scientific reputation was set.
But it was only when his theory’s prediction of the bending of starlight by the Sun was demonstrated during an eclipse in 1919 that he became a household name. “Revolution in science - New theory of the Universe - Newtonian ideas overthrown” ran the headlines in the Times on 7 November, 1919. And they were right. But how did they know?
And why did the rest of the world care? Visiting America in 1921 he lectured to an overflowing hall at Princeton and remarked, “I never realized that so many Americans were interested in tensor analysis.”
We’re familiar with the cult of celebrity today, and we’re used to seeing how reputations can be created and destroyed overnight on the whim of an anonymous reporter, editor, or blogger. Our worship of fame is balanced only by our cynicism about it. In the scientific world where I live, it’s almost accepted as an axiom that any scientist who gets on television is a fake. And yet I’ve also experienced that even scientists will be more likely to attend a talk by someone they’ve seen on TV.
But unlike the three-month half-life of today’s radioactive reputations, Einstein’s fame has survived for nearly 100 years. It has endured anti-Semitic outrages in Germany, anti-Communist hysteria in America, and the thirst of glory-seeking pop historians to topple every statue in sight. And, most remarkably of all, that reputation has proved to well-deserved.
There were no shortage of giants in the 20th century science – Curie, Bohr, Eddington, Lemaître, the list seems endless – and every year brings another new dozen winners of Nobel prizes. Indeed, many elements of Einstein’s theories had already been suggested by Planck, Lorentz, and others. But where they were suggesting tweaks on classical physical models, Einstein recognized in their tweaks a basis for a whole new way of looking at all of physics. He transformed the way we understood very nature of physics itself.
Galileo and Newton had shown how the action of everything could be reduced to mathematical laws in a relentless application of common sense that threatened (as Blake and the Romantics complained) to reduce all of life to mere mechanical cause and effect. Today we appreciate that such mechanisms are but approximations of a fundamentally unpredictable universe. But between Newton and the quantum revolution, Einstein did a far more surprising thing.
He showed that even the predictable could be unexpected; that even in a mechanistic universe, you can’t take anything for granted. The warped space-time of General Relativity has resisted the best attempts of a century of popularizers to explain in a way that doesn’t boggle the imagination; but nonetheless it remains the best theory to explain what we observe both in our measures of the cosmos and the workings of the atom.
Blandly applying the lessons of relativity to everyday life almost always gets it wrong. Relativity certainly does not say that “everything is relative”; indeed, it says they opposite, postulating an unchangeable entity – the speed of light – that remains constant and true in every frame of reference. Nor did it mean the downfall of Newton’s laws, which remain our best approximation for most ordinary circumstances.
The biggest jolt of relativity in fact is that it is a startling counter-example to Occam’s Razor. It is a case where the simplest explanation – the common sense of Newton and Galileo – turned out not to be correct.
And so maybe, in its way, Einstein’s fame is also an antidote to our cynicism. Sometimes, the newspapers get it right. Sometimes, the popular fascination is deserved. Sometimes, glory is more than a marketed commodity.
This column first ran in The Tablet in March 2017
What do you tell a room of bright young high school science students? That has been my challenge recently, visiting Jesuit high schools across North America. Pope Leo XIII wanted the Vatican Observatory to show the world how the Church supports science; while the other Jesuits have been doing the science, I’ve been “showing the world”.
The hardest but most important message for these students to hear is the need to look beyond the math and sciences they love, to treasure as well other course work that they might find more difficult to appreciate. Unlike in Britain, schools in America are less likely to narrow their focus purely into “arts” or “sciences” tracks, but the students themselves may well gravitate into the sciences because they feel awkward in the disciplines where they feel less talented.
Science is a field of exciting ideas; but it’s the arts that provide an essential education in how to communicate those ideas. Communication is exactly the skill that every scientist needs to master. If you can’t tell people what you did, you might just as well not have done it. Your colleagues must be able to understand your results; but more, you need to be able to explain compellingly why your results matter. (And why anyone should give you a grant to do more of it.)
This means public speaking… art… writing. Writing means reading; you only learn to write well by reading things that are written well. But even more, the exercise of analyzing a poem or a play is exactly the same skill you eventually use to analyze data. (Or someone else’s scientific paper.) The place where I learned how to “analyze data” was in fact in high school English literature class, where we learned how to pull apart a poem, see how the different lines and words worked, and put it back together.
I found when I was teaching university physics that my best students had all had Latin in high school. I don’t think that was only just because the best students in American high schools are tracked into Latin classes! But there’s more to it than being trained in the rigorous logic of Latin grammar; an ability with any foreign language gets you used to looking at things you have taken for granted from a completely different context and point of view. (One school I visited, Belen Jesuit Prep, is fully bilingual; it was founded in Havana and transplanted to Miami in 1961.)
A basic knowledge of art and the fundamentals of graphic design are essential. When competing teams wind up doing similar work (a fairly common occurrence, in science) the team whose paper is most cited is usually the one with the clearest and most compelling diagrams. A good plot is something that can make your paper, and your reputation.
At scientific meetings nowadays, most work is presented as posters; thus every scientist needs to learn how to do layout properly. And if your work is chosen for one of the valued oral presentation slots, you’ll need to know how to prepare a Powerpoint presentation that can communicate both your ideas and the excitement behind them, free of useless and distracting bells and whistles. This of course also points up the essential need to be comfortable speaking on your feet, to know how to connect with an audience.
Astronomy is not stars and planets. Astronomy is human beings talking about those stars and planets. Sharing ideas and questions and dreams. The very arts that make us richer people, make us better scientists. Or, maybe, it works the other way around.
First published in The Tablet in February, 2006
Long rows of weedy plastic motel rooms spring up in the hard barren sands of the desert surrounding Tucson, their walls scoured by the creosote-scented winds and stripped of color by the relentless sun. In winter the surrounding asphalt seas shine with fleets of cars fleeing the cold of the north. The invasion reaches its peak in the first two weeks of February. That’s when the downtown Tucson convention centre, the main ballrooms of the larger hotels, and every motel within miles (plus more discreet, upscale shows in outlying resort regions) are filled with tens of thousands of rock hounds and gem dealers attending the annual Tucson Gem and Mineral Show: the largest in the world.
Tents in parking lots arch over tables covered with fossils from Morocco and rich ores from Argentina. Within the motels themselves, each room becomes a little shop. Walking down the hallways – or, more commonly in Tucson, past rooms that open directly to the parking lots or outdoor pools – all the doors are open, marked by little signs identifying the dealers’ names and origins. Look inside, and on every free surface you see bowls of precious gems or display cases of (sometimes questionable) antiquities. Squatting on the motel beds among the remains of breakfast are the proprietors, chatting importantly with other dealers while keeping a careful eye on their wares.
Walking among the waves of grainy amber, I keep wondering what attracts all these people. I have never understood the joy in jewelry; even rubies look like just a pile of rocks, especially when they are filling plastic bowls in this particularly unglamorous setting. But hidden among the gem and mineral sellers are a handful of dealers in the one sort of rocks that does interest me: meteorites. They’re selling space rocks bought from nomads in the Sahara – meteorites stand out atop the desert sands – or collected from recent falls in Europe or America.
I have come to this show with a credit card and an $11,000 line of credit from a colleague’s institution, their designated agent to help assemble a teaching collection of meteorites. The cost of these dirty black stones and misshapen lumps of iron can sometimes range up to hundreds of dollars per gram.
Thanks to the competition from collectors, research institutions find it an expensive proposition to get samples for science. But thanks to the same collectors, these dealers find it worth their while to go hunting and gathering these samples. Without them, the samples would not be so expensive, yes: but without them, the samples wouldn’t be available at all. The Vatican’s collection itself was assembled a hundred years ago by a French nobleman, a private collector who would have loved this show.
I have my own native guide, a researcher from California who is herself also a collector. The dealers’ eyes light up when she enters the room. She knows from experience whose wares are trustworthy, what prices are fair. My own work as curator of the Vatican’s meteorite collection has trained me to recognize good samples and significant names. Together we trade meteorite-hunting stories with the dealers, and negotiate our purchases.
Within those unprepossessing meteorites are tiny clues to our understanding of how the solar system was formed and how it functions... clues that are as precious a treasure as the gems being traded in these equally unprepossessing motels rooms scattered about the Tucson desert. It will take years of work to put that data into its proper context; but likewise with luck each ruby in each plastic bowl will someday find its proper setting in a piece of jewelry.
I look again at the crowds thronging through the Gem Show and wonder anew at the Creator’s habit of hiding the most wonderful of things in the most unlikely places. As for the jewel in each one of us... when will it find its proper setting?
First published in The Tablet in February, 2005... and on The Catholic Astronomer several years ago. Note that Spirit and Opportunity, originally designed to be a 90 day mission, have now been in operation for more than 5000 days!
In January , the Opportunity rover that has been trundling across Mars came upon a pitted lump of iron and nickel, about the size of a basketball. The rover’s chemical tests confirmed that it had found an iron/nickel meteorite, a stray bit of a broken-up asteroid fallen from the sky, with a composition like those that have fallen onto the Earth.
A lump of metallic iron is not what one would expect to find on Mars. The Martian atmosphere is rich in carbon dioxide; the oxygen from that carbon dioxide, and from the water we now know once flowed on the surface, should be enough to turn metallic iron into a rusty pile of iron oxide. And in fact, oxidized iron is what we normally see on the surface of Mars. That’s where it gets its red color. The high nickel content is another clue: when planets are formed, that rusting process separates the nickel from the iron, with most of the nickel winding up deep in the planet’s core.
Indeed, since the Mars iron was found on a flat desert plain as bleak as the South Dakota badlands, far from any Martian volcano or other source of rock, it’s pretty easy to conclude that outer space is the only place it could have come from.
It’s no surprise that meteorites would be found on Mars. [In 2000], Phil Bland and Tom Smith at the Open University calculated that Mars should have many more meteorites on its surface than Earth does. Given the thin air and cold temperatures, meteorites rust away more slowly on Mars than on Earth. And since Mars lies halfway to the asteroid belt from us, those space rocks don’t have to travel so far to reach its surface.
Indeed, Bland and Smith warned that probes to the Martian surface will have to pay attention to be sure that any rock they analyze, thinking it came out of the interior of Mars, is not in fact a stray bit of asteroid.
How could you tell? It’s not a trivial problem to do remotely. If you have a sample in the lab, you can measure things like oxygen isotope abundances which vary distinctively from planet to planet. Or you could look for the decay products of radioactive elements made inside the meteorite when it was exposed to cosmic rays while traveling in space. But the only obvious test that the Mars robots can do is to measure the iron and nickel. Mars rocks are rusty, while most meteorites are not.
Most meteorites; but not all of them. We have found about two dozen rocks on Earth with exactly the same chemical composition as Moon rocks; we can tell, because we have Moon rocks in hand that the Apollo astronauts returned. (In fact, one of those Apollo rocks contained a bit of meteoritic material; meteorites can be found on the Moon, too.)
But there are also another couple of dozen different meteorites whose compositions indicate they are relatively young, some a mere hundred million years old, unlike the 4.5 billion year age of most other meteorites. And they come from a place with air rich in carbon dioxide, and perhaps some liquid water. In other words, we think they come from Mars itself. One of them even has bubbles of gas trapped in the rock with exactly the composition of Mars’ atmosphere.
The only problem here is that, judging from what we’ve seen from our orbiters and landers, most of Mars’ surface is covered with a kind of rock different from most of the purportedly Martian meteorites. So it was with some relief when in April 2004, the Opportunity rover did come across a rock on the surface of Mars with the same composition as our “Martian” meteorites. Proof, it was thought then, that those meteorites did indeed come from Mars.
But it’s always possible that there is some other source for those meteorites. Maybe what we found on Mars last April had also fallen there from space – just like our lump of iron.
Most scientists, including me, are pretty confident that’s not the case. Mars is the only place we know that’s big enough to have stayed molten inside, up to a hundred million years ago when the meteorites crystallized out of their lava. (All the asteroids, and even the Moon, have been cold and solid for billions of years.) And the Mars atmosphere has evolved in a strange way; it’s hard to imagine that another place could have reproduced the composition of the air seen in the Martian meteorites.
But confidence is not proof.
And that’s all right. Science does not deal with proofs; it describes, it does not prove. When more evidence lets us improve our descriptions, we’ll happily change our textbooks. A real scientist would never insist that any one given description is absolutely correct.
Indeed, all of life consists of making decisions, and carrying on, without any surety of absolute proof. Whether it is belief in Mars rocks, or belief in God, we ultimately can only decide which description makes the best sense of the things we do know, in the light of our own experience of how we’ve seen the universe work.
[This is by no means the only iron meteorite found on Mars, as outlined in this Sky and Telescope article...]
This column first ran in The Tablet in February 2017
A paper just posted online by two Caltech astronomers describes observations at an 8-meter telescope of more than 300 faint TNOs (Trans-Neptunian Objects), small lumps of ice orbiting out beyond Neptune. These are leftover chunks of the materials that went into the planets, witnesses to the events that formed our solar system. The shapes of their orbits tells us how the large planets near them have pulled on their paths over time; patterns in the evolution of their surfaces hint at events in our solar system over the last four billion years.
Nearly twenty years ago I started working on just such observations with Steve Tegler (Northern Arizona University) and Bill Romanishin (University of Oklahoma). Back then, Steve and Bill had first noticed that the first handful of TNOs they’d observed didn’t show a range of colors but rather fell into two distinct color classes, red and gray. Looking for a telescope where they could continue their survey, they asked to use our 2-meter Vatican Advanced Technology Telescope. I operated the telescope, while chiming in on their all-night speculations as to what it all meant.
We found that the red/gray split in the colors didn’t apply to objects in more well-behaved circular orbits; those were just red. Methane ice turns red when it is exposed to the sun’s ultraviolet light; perhaps all TNOs were once reddened this way, but maybe the ones with disturbed orbits experienced impacts that churned up fresh, colorless ice to their surfaces. But when we observed these bodies as they spun, we never found any that were red on one side and gray on the other, the way you might expect of an old red surface hit by a recent impact. And careful measurements in infrared light showed that the gray surfaces, rather than being fresh ice, were actually much darker than the red surfaces… more black than gray.
Even after observing for twenty years, we only have data on about 150 such objects – each object essentially represents one night of observations. Meanwhile, other astronomers observing these bodies haven’t seen as clear a trend as we have. It’s become a minor controversy. Now this new paper triples the number of bodies observed, and measures objects much fainter, much smaller, than our telescope could see. The new results? Like us, they see that TNOs with disturbed orbits come in two distinct colors, red and gray.
It’s a delight to have our observations validated… except, reading this new paper, I find no reference to any of the papers that we’ve published on the topic over the last 20 years. It cites other papers in the controversy; but not ours. Probably the authors were just sloppy. Still, I am miffed.
But should I be? It’s not as if Steve, Bill, or I need the credit to build up our careers. I am already an observatory director, Steve is a department chair, and Bill is now retired. Shouldn’t the validation of our science, the truth itself, be enough?
Science is a “gift economy;” your status is earned not by how much you accumulate, but by how much you give. References to your papers is one way the value of your gift is recognized, one of the few rewards you get for your hard work. It keeps the community of science alive.
Science is not the data; it’s the community who ponder the data. Like all human communities — think of the Church — we can never forget that our labour relies on the labour of others around us. Like our data, we too need validation.