Across the Universe: Tom Swift and his Helium Pycnometer
This column first ran in The Tablet in July, 2004...and again, here, in 2015
This is Bob Macke in 2004 or so, making measurements in the classroom at our old quarters in the papal palace. Why had we taken over the classroom for our work? Because, unlike the lab, it was air conditioned...
Looking over my shoulder at the computer screen, Bob Macke starts telling me about a cartoon he’d seen on an office door at MIT. ‘The first panel,’ he says, ‘was a guy labeled “cartoon scientist,” surrounded by boiling test-tubes and sparking electrical equipment, shouting that he’s discovered the Elixir of Life. The second panel, labeled “real scientists,” was just a bunch of people looking at a computer screen, and one says to the other, “I think our data point should be plotted in red.”’
I give him a dirty look. Two keystrokes later, and our data points are now plotted in red.
It’s two weeks before I leave for the annual meeting of the Meteoritical Society, and I’m busy trying to prepare three papers.
One is a collaboration with a colleague in Pennsylvania. I’ve posted a rough draft of our paper on a web page for him to download and comment; two weeks, and I still haven’t heard back from him.
The second paper is to be presented by a colleague from Michigan. She’s e-mailed me her Powerpoint presentation, asking for my comments. The most glaring problem is that on the first slide, my name is misspelled. More subtly, I realize that I don’t believe half of the data points that she got from me. I need to go back and measure things more carefully. With luck we’ll have time to correct both mistakes before she gives her talk.
The third paper is the most challenging. We submitted our summary back in April, just before the meeting deadline, in full knowledge that none of the data we said we’d be reporting actually existed yet. Now it is summer, and I’ve been joined here in Castel Gandolfo by a young Jesuit brother from Missouri, Bob Macke, who’s trying to figure out how to make my lab equipment work. Finally, after ten days, we have some data points to plot.
Bob’s just 30, born the year I graduated from MIT. He went there, too, class of 1996; we have a double bond, Jesuit and Techie, of common experiences. On his computer desktop are images of the X-Prize competitor that recently broke the space barrier, the first private spacecraft to reach an altitude of 100 km. There’s a little “Tom Swift” in me, too, still dreaming of adventures in space.
We’ve got a new machine in the lab, a helium pycnometer, that measures the densities of porous rocks (like our meteorites). The sample is put in one cell, pressurized with helium; the more space taken up by the rock, the less space there is for helium. When the helium is allowed to expand into a second cell, the change in pressure lets us calculate the volume of the rock. Divide that into its mass and we get its density.
Bob is comparing these densities with other physical parameters of the meteorites, looking for trends. We’re concentrating on multiple stones taken from the same meteorite shower, comparing the measurements from stone to stone. We’ve already come across a couple of “ringers”, meteorites that don’t fit with the others. Is this telling us something about inhomogeneities in the asteroids? Or is it just that a couple of samples have gotten mislabeled and mixed into our set by accident?
‘What is this all going to mean, even if we do find out that showers of falls are not all the same?’ Bob asks me.
I was a little leery of having a stranger in my lab. I am used to working alone, nobody watching me when I take a break to ‘think things over’ while playing solitaire or reading the newspaper on-line. Nobody asking me embarrassing questions.
‘It’s a fishing expedition,’ I admit. ‘We take the data now, plot everything versus everything else, and see if something interesting pops out. Probably we won’t learn a thing. But every now and then, something unexpected comes up out of the data.’ It’s true; six years ago we stumbled across a new understanding of asteroid structure in just that way.
But the real reason is even less scientific. It’s an excuse to play with the rocks. The dark glassy balls of stone and iron covered with fusion crust, the grains of minerals that have spent most of their existence in outer space, excite my imagination. I love to hold them, I love to look at them, I love to measure them and tease out of them whatever little secrets they may hold. Those rocks and I share a common Creator.
I’m a material guy, living in a material world. It’s not enough to look at a mountain, I have to climb it; it’s not enough to look at a lake, I have to jump in and swim in it. It’s not enough for me to look at the stars; I want to handle bits of stuff from them, feel their physical presence, know for sure that they and I share the same universe. And I still dream of some day getting to go there, where they came from.
Bob Macke SJ joined the Vatican Observatory staff full time in 2013, and he is now the Curator of Meteorites in Rome, my old job. He still plots his points in red.
Across the Universe: Hidden Complications
This column first ran in The Tablet in July 2017
Following on last week's reposting, here's yet another Juno column!
[Two years] ago, Nasa’s Juno spacecraft entered Jupiter orbit (as described in my Tablet column for July 2016). Its highly elliptical path periodically brings it close to the tops of Jupiter’s clouds, and this month one such low pass brought it right over the famous Red Spot, a hurricane-like storm some three times larger than planet Earth. The storm appears to have been raging in Jupiter’s atmosphere for at least three hundred years; Cassini first described it in 1665, though the first color depiction of it is in a painting from 1711, on display in the Vatican Museum. The internet is now full of glorious, if somewhat gaudy, images of swirls and eddies seen by the Juno camera.
This painting by Donato Creti, one of a series in the Vatican Museum, is the oldest color depiction of Jupiter's Red Spot. It dates from 1711.
In fact, the camera on the Juno spacecraft was an afterthought. Since the science team was put together to probe Jupiter with other instruments, the raw images from the camera are being provided freely to the public, where an army of amateurs armed with software packages like Photoshop have been playing with colour and contrast to bring out scientifically interesting details in the storm clouds… and make eye-candy desktop images.
Jupiter’s Great Red Spot imaged by Juno on July 10, 2017. Credit: NASA/SwRI/MSSS/Jason Major
Juno itself has a deeper mission: to explore the interior of our gas-giant neighbor, the largest planet in our solar system. We already knew certain parameters about this planet; it’s easy to observe even in a small telescope, and half a dozen other spacecraft have visited it. It’s made mostly of hydrogen and helium, not all that different from our Sun but ten times too small to support fusion reactions to shine as stars do.
The cloud tops are mostly ammonia and water, colored with sulfur-based compounds. It spins so fast that its equator is visibly puffed out, and its poles flattened, compared to a perfect sphere. And it has a strong magnetic field, generated by a churning, convecting electrically-conductive fluid deep in its interior. (The central pressures may not be high enough to fuse the hydrogen into helium, but they can squeeze the electrons away from protons and let them flow freely, the way that currents flow in a metal.)
But how uniform is Jupiter’s composition? How deep can you find cloud layers? How well defined is its core? One way to address these questions is to plummet a small probe into Jupiter; the Galileo mission did that back in 1995. Its results, however, didn’t match any of our expectations. Were all our theories wrong? Did the probe malfunction? Or is Jupiter just more complicated than we expected?
Juno was designed exactly to address those questions. Rather than using visible light, it measures radiation in microwaves, emitted from deep inside Jupiter. By orbiting close to the cloud tops, it can detect small changes, lumps and gaps, in Jupiter’s gravity and magnetic fields.
It takes a while to collect data from these instruments and make sense of them. But this month, along with the fancy Red Spot images, a first look at the actual science data from Juno was published in the journal Nature Astronomy in July 2017. The results so far? Jupiter’s core is bigger and less well defined than theories had predicted; many layers of clouds, and widely varying amounts of ammonia, lie beneath the clouds we can see; and the magnetic field is stronger and more complicated than anyone had guessed.
In other words, the results are surprising but not unexpected. I’ve never heard of a planet (or a person) that turned out to be simpler than expected.
The bigger questions of Jupiter’s formation and evolution remain to be solved. Check back next year! Meanwhile… enjoy the Red Spot images.
Across the Universe: It’s A Small World
This column first ran in The Tablet in July 2016
On July 4, 2016, the Juno spacecraft went into orbit around Jupiter, beginning its mission to probe the interior of our solar system’s largest planet..., and undoubtedly it will be years before we really know what we’ve found there. [The latest results can be found here.]
Even though my own research has little to do with Jupiter, I have a personal stake in this spacecraft. Back ten years ago when NASA was deciding what their next big mission would be they solicited proposals from the community, and Juno was one of five possible missions reviewed by a panel of experts. I was one of those experts [as described in an earlier Across the Universe posting, here].
The Juno proposal addressed a fundamental question about gas giant planets like Jupiter and Saturn. (Hundreds of such gas giants have been discovered orbiting other stars, as well.) Are they lumps of gas that didn’t quite grow big enough to become stars themselves while they were forming within a larger star-forming gas cloud? Or did they start as solid planets that grew big enough to trap lots of gas from such a cloud? Whichever theory turns out to be right will shape how we understand the origins of stars and planets.
Jupiter is the perfect test case. By measuring its gravity field in great detail and learning the chemical composition of its deep interior from its microwave radiation, we think we can resolve one way or the other whether Jupiter has a rocky core or if it is a gas ball like the Sun. Of course, nature being what it is, the truth will probably be more complicated than either of our theories!
Our review panel was quite impressed with the Juno proposal… and worried that NASA wouldn’t select it because the science, while important to the experts, would be hard to explain to the average layperson. So at the last minute, the mission added a camera to send back ordinary images of Jupiter. That will help bridge the gap between the abstract data underlying our theoretical constructs, and the real, recognizable planet Jupiter.
See intricate cloud patterns in the northern hemisphere of Jupiter in this new view taken by NASA’s Juno spacecraft. The color-enhanced image was taken on April 1 at 2:32 a.m. PST (5:32 a.m. EST), as Juno performed its twelfth close flyby of Jupiter. At the time the image was taken, the spacecraft was about 7,659 miles (12,326 kilometers) from the tops of the clouds of the planet at a northern latitude of 50.2 degrees. Citizen scientist Kevin M. Gill processed this image using data from the JunoCam imager. JunoCam's raw images are available for the public to peruse and process into image products at: www.missionjuno.swri.edu/junocam More information about Juno is at: https://www.nasa.gov/juno and http://missionjuno.swri.edu Image credits: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill
I have another connection with the Juno mission beyond my role in helping choose it. About half of principal scientists who’ll be studying its data are personal friends of mine. They include an old professor who sat on my PhD committee; someone who was in graduate school with me; even a classmate from my high school days. One of them is a close associate of the Vatican Observatory who’s become a convert to Catholicism. Another member of the team, back when she was a graduate student, shared the apartment of a woman I was dating in my pre-Jesuit life.
Jupiter may be a gas giant planet but the community studying it is a small world. There are fewer than a thousand active planetary astronomers in the world; we all went to the same schools, we all attend the same meetings. Another example of small worlds: a dwarf planet orbiting beyond Neptune has been discovered just this month [2017]; the announcement was made by Michele Bannister, who was a student at our 2007 Vatican Summer School. [For more about this, see her fascinating article here.]
Also falling in July, two days after Juno’s arrival at Jupiter, is the feast of the child saint St. Maria Goretti. She lived near our observatory headquarters in Albano, Italy, before her tragic death in 1902. I’ve heard her great-niece speaking at the local cathedral.
Scientists and saints aren’t mere theoretical constructs. You probably know someone who has met one. For that matter, you can see Jupiter for yourself this month: a bright star setting in the evening sky.
[The Juno mission is a popular subject of posts here at The Catholic Astronomer; do a search and you'll find at least two dozen of them!]
Happy Birthday to the Father of Astrophysics!
Father Angelo Secchi, sometimes called the Father of Astrophysics, was born 200 years ago on this day (June 28). [Note that many sources get his birthday wrong, thinking it was the 29th. He was born on the 28th, baptized on the 29th, according to his biographer Dr. Ileana Chinnici, who's seen the documents in question. Also many sources think that he had a first name beginning with a P, often listed as Pietro, because he was often referred to as "P. Angelo Secchi" but in fact the P there stands for Padre, signifying that he was a priest.]
Secchi's work at the Roman College attracted great positive attention the science and the Church at a time when both were under attack... and probably led to the foundation of the Vatican Observatory a few years after his death in 1879.
Father Chris Corbally has written a short piece about him which is running in the American Astronomical Society's This Month in Astronomy Posting -- to read it, Click Here.
Fr. Angelo Secchi SJ was the first person to classify stars by their spectra... a novel idea scorned by many of his contemporaries. This plate is from his c.1870 book.
One of the odd but wonderful things that Secchi is known for is the "Secchi Disk", a device he invented more than 150 years ago which is still used today to measure the clarity of water in rivers, lakes, and oceans. Bob Macke wrote about it for the Limnology society. Click Here for the link to his article.
Here is a Secchi Disk:
Secchi disk as offered for sale at lyonscientific.com
Across the Universe: Deep Impact
This article from The Tablet was first published in June, 2005, thirteen years ago, just before the "Deep Impact" probe hit. (And rerun here in 2015.) It's interesting to see what we were hoping to learn… how little we knew; how little we know.
The impact of comet Tempel 1 in 2005. Credit: NASA
The folks who work out the celestial mechanics of space probes are a clever bunch, with a techie’s sense of humor. A few years ago, the NEAR spacecraft arrived at asteroid Eros on Valentine’s Day. The ill-fated Beagle 2 probe was designed to land on Mars on Christmas morning (not the only present that Christmas to arrive broken, I suspect). And this year [2005], on the Fourth of July, an American probe called “Deep Impact” hopes to make a splash as dramatic as any fireworks display by plunging at 37,100 kilometers per hour – London to New York in nine minutes – into the nucleus of the comet Temple 1.
Before the space age, all one could see of a comet were its spectacular tails of gas and dust. Obviously those tails must emanate from some dusty and gas-rich clump of material. The tails appear only when that nucleus comes close to the Sun, and they repeat over many apparitions; so presumably, far from the Sun, the gas was frozen as ice. Thus when ESA’s Giotto spacecraft approached Comet Halley in 1986, they expected to see a nucleus that looked like a “dusty snowball.” Instead, what they saw was a jet-black lump.
But of course... as the ice evaporates away, it must leave behind a crust of dust. To see the ice, what you’d need to do is poke through that crust. In the process, you’d probably expose a huge amount of fresh ice and create a spectacular fountain of gas and dust, easy to observe from a nearby spacecraft and indeed probably quite visible from Earth.
That was the idea behind the first comet-impactor proposal in 1996. Improved, with a way to steer the impactor into the comet and a name taken from a Hollywood blockbuster, NASA funded "Deep Impact" in 1999. After the usual trials and delays, it finally launched in January, 2005. Except for a few camera glitches, all seems well for the spacecraft on its way to its Independence Day encounter.
It takes six years to build a spacecraft mission to a comet. But it only takes a few pictures, and a few calculations, to change our ideas of what a comet really looks like. Today’s theoretical picture suggests that the comet imaged by Deep Impact’s cameras could look a lot different from what they expected in 1999.
For one thing, comparing the densities of asteroids with the meteorites that come from those places (including work I’ve done with the Vatican collection) shows that these small solar system bodies are not solid chunks of material but very loosely packed piles of rubble. Meanwhile, other spacecraft (Deep Space 1 and Stardust) have sent us images of comet surfaces that suggest the the dark, ice-poor crust could be quite thick. There’s plenty of cracks for all but the deepest gases to escape, and most of the comet tails seen today come out of only a few small regions of the nucleus’ surface.
So the impact could be a big “dud” – poking a dimple into the side of the comet without revealing anything new. Some wags have even suggested that the probe might pass entirely through the loose comet core and come out the other side! That’s not likely; this comet is about ten kilometers thick. But it is possible that rather than exploding on its surface, the impactor might be captured intact. Such a result might not make a spectacular show, but it would be very interesting to the scientists.
Until the impact occurs, we just won’t know. And even as these questions are answered, new ones will arise. Compared to 1999, we now know better how little we knew about comets when the mission was planned. The more you learn, the more you realize how little you know.
[Note from 2015: The impact was neither a dud, nor quite what we expected. It did not plow entirely through the comet! In fact, the impact produced so much light that it momentarily blinded the cameras, so that at the time we didn't see the impact crater. Only several years later did another probe, the one sent to comet Wild 2, manage to get images of the small but real crater produced by Deep Impact.
It took a long time to finally reduce and understand the data from Deep Impact. Here is a summary of its results, written in 2013. In the same way, it will take years to understand the Rosetta mission that landed a probe much more gently on a comet, late last year, or the results soon to come from New Horizons.]
Across the Universe: Members of the Band
This column first ran in The Tablet in June 2017
June 2017 marked the 50th anniversary of the Beatle’s Sgt. Pepper album, and of the Fermi National Accelerator Laboratory. Visiting Chicago that month, on my way to buy the Sgt. Pepper re-issue I found myself driving past Fermilab.
Nothing says "big science" like a particle accelerator. This was Fermilab in 2012
The main building of Fermilab, 16-story Wilson Hall, is two curved slabs shaped like hands in prayer. It’s been compared to a French gothic cathedral. Rising above the flat Illinois prairie, it’s easily visible from the highway I was on – Kirk Road.
The comparison to a church goes beyond its architecture. Fermilab is a classic example of “big science.” For 50 years it’s been home to 1750 scientists and engineers, working on projects ranging from the discovery of subatomic particles to the exploration of the nature of the neutrino. By generating the building blocks of the universe, then smashing them together, they’ve both confirmed and challenged our theories of how reality works.
I remember one of the current principle investigators there when he was a student at MIT many years ago, a squeaky-voiced freshman while I was a lordly senior. And I’ve met a number of Jesuit scientists who have worked at Fermilab over the years. But the folks at Fermilab whom I know best, the friends I was visiting this week, are engineers and technicians there. Like lay brothers supporting the work of the scientist-priests, they keep the machinery running, and keep the experiments safe.
Todd Johnson with one of Fermilab's toys...
...and Todd with a gizmo he made at home, using sound waves to estimate the volume of a meteorite
Every Wednesday evening a group of them — reminiscent to me of the famous Oxford “Inklings”, C. S. Lewis and J. R. R. Tolkien and friends — gather at a local diner to swap stories…
A video camera on a wire, meant to inspect welds inside a pipe within the accelerator ring, kept getting snagged in the pipe’s bends; so one guy drilled through some bocci balls and ran the wire through them to keep it off the sharp corners. The scientists wanted a 3-D computer visualization of a new control room; another engineer borrowed the software from a graphic computer game called Doom, inserted images of the proposed room layout, and then at the end of the demo hit a few control keys to reveal that the shoot-em-up aspect of the graphics package was still intact! Meanwhile, other members of the gang show off gizmos made in their basements, just for fun: a tiny piston that spins a wheel, operating off the heat from the palm of your hand; a singing Tesla coil (search “Zeusaphone”)…
The Fermi scientists may work to uncrack the mysteries of the universe, with perhaps a bigger grant or even a Nobel Prize as further inducement. The engineers do their work simply for the joy of making really cool stuff. In both cases, the work itself is more than any one person could do alone. The scientists would be helpless without the mile-wide accelerator ring built and maintained by the engineers; the engineers would never have the chance in their own basements to build the beautiful machinery that they get to use every day. But then, could someone “find Jesus” without the infrastructure of a church that preserved and transmitted who Jesus was and what He taught? We need big religion like we need big science.
Driving home, I listened to the new extra CD of Sgt. Pepper, with early takes and studio chatter. It was fascinating to hear the songs in progress, noting the bits that John, Paul, George and Ringo each contributed. But none of the out-takes matched the glorious version of the final album with all of them playing together… enhanced and preserved by the team of recording engineers.
A letter from a Faith and Astronomy Workshop alumnus
Dear Br. Guy: Fr. Timothy Sauppé here.
I was in the 2015 inaugural seminar class at which you challenged us to take back to our parishes what we learned that week. Well, as you know, since then I have been holding Star Parties at our local county park and giving talks on the effects of light pollution.
Most recently, I have had a commemorative bench installed and tomorrow we will honor a former parishioner who controlled 15 of the 70 earth and space based telescopes on August 17, 2017 and helped with the detection of the cosmic event from 130 million years ago that become GW170817. He name is Dr. Jeff Cooke and he will be honored by our city and parish at 11 AM. Here is a layout of the bench’s back which we filled with scientific information and pictures.
Here's the commemorative bench back.
Pope Leo XIII would be proud.
God Bless, Fr. Sauppé
This is a good place to remind folks that starting on September 1, we will be taking applications for the 2019 Faith and Astronomy Workshop, to be held at the Redemptorist Retreat Center north of Tucson on January 14-17, 2019. Stay tuned for further details!
Across the Universe: By Paper, to the Stars
This column was first published in The Tablet in June, 2004, and first published here in 2015... read the end to find out what happened!
An artist's concept of Juno at Jupiter. The mission will be the ninth to visit Jupiter, and the second to orbit it. Credit: NASA via Wikipedia
The people who design airplanes say that a plane can’t fly until its weight is matched by the weight of its paperwork. The same must be true for launching spacecraft to another planet. Last month [May 2004] I took part on a NASA panel in Washington DC, reviewing five competing plans to build a planetary probe; in the run-up to the panel I was shipped 30 pounds of paper to read.
NASA’s “New Frontiers” program is a development of another project driven by piles of paperwork: the Solar System Decadal Survey commissioned by NASA and executed by the National Academy of Sciences in 2002. After hearing from hundreds of planetary scientists at meetings around the world (and reading white papers solicited and gathered by various international societies) a committee of graybeards outlined where NASA should be spending its money over the next ten years.
Among their recommendations were four straw man missions, detailed outlines of possible space probes that NASA could pull off for about $700 million dollars. They proposed: to measure the atmosphere and surface of Venus; to sample the far side of the Moon; to probe the chemistry of Jupiter’s deep atmosphere; or to visit a comet and return with a chunk of its ice.
NASA issued an “announcement of opportunity” last year [2003], for proposals to do any one of these missions. Five teams responded (one straw man mission attracted two competing groups). Each team had a Principle Investigator, responsible for running the show, and at least a dozen other senior scientists drawn from academia; an equal team of engineers affiliated with whichever aerospace company proposed to build the hardware; and an outfit like the Jet Propulsion Laboratory in California or the Applied Physics Laboratory in Maryland to manage the assembly, launch, and flight of the spacecraft.
The proposals I reviewed outlined the exact instruments the teams hoped to fly, the rockets used to put these instruments on their way, and the kind of scientific results the proposers expected to get. They also included the credentials of the team, and a budget. No surprise that each proposal wound up weighing several pounds.
Fourteen of us met for four days to look over their science and judge if their plans were coherent, convincing, and likely to work. Will that measurement really yield the crucial data point we need to resolve an important conundrum, or is it just something that’s easy to measure, but otherwise meaningless? Will the actions of one experiment contaminate the results of another? If they propose to bring back a sample, have they thought through what they’re going to do with it when they get it back to Earth?
Another team, of engineers, looked over the same proposals from a technical standpoint: can their rocket actually lift their spacecraft off the ground? Do their proposed orbits make sense? Do their proposed instruments actually work the way the scientists claim?
We didn’t rank the proposals against each other, but graded them against an absolute scale (poor to excellent), giving a terse summary of each proposal’s strengths and weaknesses. At the end of the process, a month or so from now, one or two – or none – of these proposals will pass this first hurdle and their teams be given a few million dollars to fill out these plans, shore up the shortcomings, and develop the mission to the point where an actual spacecraft could be built. (Indeed, each proposal we saw already represented millions of dollars worth of time and effort invested by the teams’ institutions.) Only then will some NASA administrator finally choose who gets to fly.
It’s a staggeringly unwieldily and staggeringly slow process. Bureaucracy always is.
The current head of NASA is criticized for being a bean-counter who’s lost sight of The Dream; his predecessor was criticized for being too much a dreamer. NASA has always been plagued by wasted efforts, cost overruns, self-perpetuating divisions, and projects driven by pork-barrel politics. Bureaucracy in general, not just NASA’s, is an easy target for people trying to identify what’s wrong with the world. I can think of many thrillers where the faceless, heartless System is The Enemy; I never read a book where it’s the hero.
But at the end of the day, these enormous piles of paper accomplish what no one individual could ever do: they can send an incredibly intricate pile of pipes and circuits hurtling off the Earth and onto another world, and have it do worthwhile tasks once it arrives. Products of this all-too-human, all-too-flawed System can tell us things we might never have imagined about the functioning of our planetary system.
If you take all of NASA’s paperwork and stack it in a pile, you can climb on up to the top and touch the Moon. Humans had dreamt of space travel since Scipio wrote of sending Roman Legions to Jupiter, but it was only these big bureaucracies -- NASA and its Soviet counterpart, now joined by ESA and the Asian giants -- that actually got us into the heavens.
It gives me a measure of perspective on certain other unwieldily bureaucracies I deal with every day.
The Juno mission to Jupiter was the eventual winner – and my personal favorite as well. It was launched in 2011 and it arrived at Jupiter in 2016! Follow that link to some spectacular images.
Across the Universe: Ordinary Time
This column was first published in The Tablet in June, 2006, and re-run in 2015 here. The coincidence of the church calendar it mentions is also true this year, 2018... the text has been slightly altered to align it with 2018's calendar. The work detailed here outlines what I was doing twelve years ago. An update appears at the end of the column.)
I wish I had more time to work in the lab. (Here: measuring a meteorite's heat capacity by seeing how much liquid nitrogen gets boiled off when I drop a sample into the dewar.) It's a staged photo, of course; I rarely wear my collar in the lab!
Next weekend marks an unusual event in our recent Church calendar: a Sunday in “Ordinary Time.” What with Lent and the Easter season, and then the special Feasts of the Trinity and Corpus Christi, Ordinary Time has been rare lately. But I’ve been celebrating “ordinary time” at the Vatican Observatory as well. Unusual for me, I’ve actually been able to manage a month’s uninterrupted work in my laboratory.
My airline’s frequent flyer program tells me I’ve flown over 27,000 miles since the last ordinary Sunday before Lent: an observing run at the Keck Telescope in Hawaii, a meeting at Nasa Headquarters in Washington, two dozen presentations from Arkansas to Newfoundland to Glasgow. Since 1996 I’ve spent more than half of every year on the road; come July and August I’ll be traveling one and a half times around the world. So this “ordinary time” now is something I treasure.
Much of this ordinary time is being spent doing an updated inventory of the Vatican’s meteorite collection. The work is simple but satisfying, weighing and photographing every sample and entering the information into a computer database. Though necessary work — without constant effort, rare samples easily get misfiled, mislabeled, and lost — it requires little in the way of creative thought. Rather, it is the kind of relaxing activity that allows the creative thoughts to come without bidding or strain.
Most of the meteorites I measure are “ordinary chondrites;” again, their importance to me is in their very ordinariness. Without characterizing what is usual, how can we recognize what is unusual? And so I measure basic physical properties like density and porosity for this kind of meteorite, which makes up 80% of all the stones seen to fall to Earth.
But are these meteorites really ordinary, or am I biased by looking at merely those samples that happen to be hitting the Earth nowadays? Perhaps most of our recent meteorites are coming from one or two nearby Earth-crossing asteroids, which for all we know could be anything but representative of material actually to be found in the main belt of asteroids orbiting between Mars and Jupiter. And who’s to say for certain that even the main belt asteroids accurately represent the material that went into forming the planets?
We know these meteorites, and the asteroids they came from, are as old as our solar system. Radioactive elements in their minerals have been decaying into stable isotopes within them, undisturbed for as long as their minerals have been solid crystals; by counting the relative isotope abundances, we can calculate that these crystals have been accumulating decay products for four and a half billion years. But that’s only a third of the age of the Universe. Old as they are, these rocks weren’t crystallized until long after the exciting events of the Big Bang were long over, and after several generations of stars had come and gone, creating the heavy elements that now make up asteroids, planets, and us. They too are a record only of “ordinary time.”
And yet, given our current understanding of cosmology, this time may be unique. Only now have stars made enough heavy elements to form planets and people, while still retaining enough hydrogen and helium to fuel the starlight that make our life possible. If the expansion of the universe goes on unabated (as, so far as we can tell, it will) then most of the Universe’s future will be cold and dark. Only now, for the next few tens of billions of years, can there be life-filled oceans and fields of foxgloves.
This is the early summertime in the life of the Universe. And to quote the poet James Russell Lowell (cousin of the astronomer Percival Lowell), what is so rare as a day in June?
(How have I been spending ordinary time this year, June of 2018? This year is an even numbered year, so that means I am in Castel Gandolfo with the students of our biennial summer school. Of course, as director, my ordinary time is very different now. I don't get to do so much research, but I do wind up writing a lot more.)
Across the Universe: DIY Religion
This column first appeared in The Tablet in May, 2005; we ran it here at the blog in 2015
Astronomy pulls you out of your day to day world and makes you realize that the universe has bigger questions than “what’s for dinner?” and “why is my boss such a pain?” But what does an astronomer do to pull himself out of a day-to-day already filled with galaxies and black holes?
My 2005 Tertianship eventually led to a book, God's Mechanics. This was the cover I wanted to use, adapted from a Popular Mechanics cover of 1923
In January, 2005, I began a Jesuit program called Tertianship, a period of study and prayer leading up to final vows where I’ve been challenged to move outside my own familiar modes of spirituality, to work outside my comfort zone. For me, that has meant working with people. For six weeks in May, 2005, I lived at Santa Clara University, talking religion to engineers and scientists in Silicon Valley.
The pattern of religious life for these “techies” is familiar: Students are consumed by questions about ultimate truth and the meaning of their own lives. Many 20-year-olds reject organized religion. By the time they’re forty they’re back in church, looking for community and a way to pass on a structure of right and wrong to their own kids. But the language they use to describe their religious journeys, and indeed the nature of those journeys, are strongly shaped by their technological culture.
Chatting with a programmer at Apple Computer, I described my surprise that so few of the 40-year-olds seemed to be concerned about religious truths in their churches. He nodded, and pointed out that they have already adopted their "operating system"; what we're selling them now is "tech support." Church as user’s group; it’s bad programming to constantly need new service packs.
Indeed, in the pragmatic, rules-oriented world of an engineer, religion itself is seen as one large book of rules for life. To some, the Bible is another computer manual, a guide to program yourself into Heaven. To others, religion is a “behavior modification system” that trains your kids not to lie or cheat or steal. To many, it is as full of useless knowledge as those unhelpful “help” programs that tell you everything you already knew, and nothing that you could actually use to fix your immediate problems. “The homilies at Mass are just so much white noise,” one engineer from a Silicon Valley start-up told me. “I use that time to meditate.”
More significantly, techies try to deduce from the rules they hear the deeper truths behind the rules. And then, like good tinkerers, they invent new rules for themselves, based on this home-brew theology, which they assume will do a better job in their own particular lives than following the received wisdom.
The actual cover to my 2008 book about techies
That’s how copier repairmen figure out how to fix their machines. As the ethnographer Julian Orr explained in his book Talking About Machines, a company like Xerox might issue a checklist of “if this fails, try that” procedures; but in the field the technicians just use these instructions to deduce a global schematic of how the machine actually behaves, so that they can fix problems never foreseen back at headquarters.
One of the joys of my time here has been talking to people like Dr. Orr. We did lunch last week, chatting over falafel and lime-flavoured fizzy water at a middle-eastern sandwich shop outside Stanford University. Retired from ethnography, he now raises sheep on a ranch near Half Moon Bay, and comes into Palo Alto occasionally to visit his acupuncturist. (Only in California...)
I met him, and many other helpful scholars, through the Center for Science, Technology, and Society at Santa Clara University. The question of how technology has changed our culture is a hot academic subject these days, fascinating to observe... from the outside.
The laws of physics are far easier to grasp than those of the human soul. And – unlike people – once a scientific question is solved, it stays solved. Usually.
The interviews described here formed the centerpiece of my book, God's Mechanics, which was published in 2008.
Across the Universe: Techie Dreams
This column first appeared in The Tablet in May, 2008, under the title "The Magic is Real" We ran it again here in 2015.
It's hard to believe but the Iron Man movie. credited with launching the current Marvel Universe franchise, is now ten years old...
In his workshop, Tony Stark (Robert Downey Jr.) works on his Mark III armor in "Iron Man." Paramount Pictures and Marvel Entertainment; Photo credit Zade Rosenthal/Paramount Pictures.
I have a friend who has found a new drug: it can keep him awake and programming at his computer for 36 hours straight, without too many bad side effects… or so he claims. I think he’s nuts; aside from the obvious dangers of self-prescribing anything, I happen myself to find sleeping to be a beautifully spiritual experience. (At least, that’s what I tell the homilist after Mass.) But I was struck mostly by the motivation behind my friend’s drug abuse. He is so passionately in love with being alive and doing his work that he resents having to waste eight hours sleeping every night.
That passion is one of the great things about being a techie. It is illustrated wonderfully in the comic-book movie, Iron Man. There, the techie hero Tony Stark builds a mechanical suit that allows him to leap tall buildings in a single bound. All my techie friends agree, the most thrilling scenes are not the flights through space or the battles against the bad guys (well done, indeed, but nothing we haven’t seen before); rather, it’s the sequence showing the hero building and de-bugging his equipment. The thrill is in the making.
Yes, the techie worldview has its limits. (What worldview doesn’t?) I’ve discussed before the odd view of religion many techies have. There is a tendency to know-it-all arrogance that gives a new spin to Anne LaMott’s famous dictum that “The opposite of faith is not doubt: It is certainty.” Some of them are so certain, they have no room for faith and its attendant doubts, and it makes them easy prey for all sorts of gnostic nonsense. The fact that the rest of the world finds your opinions to be madness just reinforces your own sense of being smarter than everyone else.
The only people who can knock the rough edges off of techie arrogance are other techies. Fortunately, for all that techies bear a reputation for being socially-inept, there is a large techie subculture – like-minded folk who met at engineering school and who constantly cross paths as their jobs move them from project to project.
They delight in gatherings of the clan. Science fiction conventions often have extensive programming on the latest developments in science and engineering, quite independent of anything that’s appeared in the fictional world – yet. “Maker Faire” gatherings at county fairgrounds offer a chance for basement mad scientists to “Build. Craft. Hack. Play. Make.”– and to show off their results. Friends of mine, far less formally organized, gather every summer on a remote patch of wasteland Somewhere in Northern Michigan to set off home-made rockets and play with things that make a Big Boom. It’s a family affair; kids are taught safety rules in a setting they won’t forget.
This techie sense of camaraderie, this zest for life, is a side of science and engineering that stands in stark (a la Tony Stark) contrast to typical adolescent cynicism and ennui. Pundits despair at the shortage of engineering students nowadays; kids need to know that the magic is real. I devoured the Harry Potter books with a deep nostalgia for my days of study at MIT. You can be a wizard if you really want; you just have to overcome your fear of maths.
A sunny May morning reminds us all of why we love nature. The techie finds an intimate expression of that love in observing, building, and participating in its laws. It’s not just to solve problems; it is for its own sheer delight. In the same way, it was not just to redeem mankind that God sent his Son; but first of all, because He so loved this world.
In August 2015 I was a guest of honor at Musecon in Chicago, a gathering of techie-makers.
Across the Universe: Transit of Venus
The original version of this article first appeared in The Tablet in May, 2004, announcing the transit as an upcoming event; we ran a version here on the blog in June, 2015.
“There’s a little black spot on the Sun today...” In the Police song “King of Pain” these words evoke an alienating sense of remoteness. But on the morning of June 8, 2004, a much larger spot was visible crossing the Sun, an event that occurs but twice a century; when it happened in the eighteenth century, it changed human history.
Transit of Venus, 2004, imaged by Ron Dantowitz from the roof of the Papal Palace in Castel Gandolfo
A “transit” occurs when we see one astronomical object appear to move in front of another. Since Venus orbits between us and the Sun, you might expect it to transit the Sun rather frequently. But the Sun is small, as seen from Earth, and the orbit of Venus is tilted slightly compared to ours, so Venus usually appears to pass above or below the Sun. It’s only when our orbits are precisely lined up that the black spot of Venus’ nighttime side stands out against the Sun’s brilliant disk. This happens in pairs, 8 years apart, about every 130 years. The last pair of transits were in 1874 and 1882.
The Venus transit was merely an astronomical curiosity when first observed, by the English cleric Jeremiah Horrocks in 1639. But in 1716, Edmund Halley (of comet fame) pointed out that the transits of Venus predicted for 1761 and 1769 provided a unique opportunity to make a fundamental measure of the universe.
By the 18th century, the observations of planets and Kepler’s laws describing their motions merely allowed astronomers to compute the relative distances between planets. Only if you could actually count the number of miles between any two planets, could the distances to all the other planets be worked out. But how do you make that one definitive measure?
Halley realized that a Venus transit let you to do just that. It’s a matter of parallax. If two people observe the same transit from two different vantage points, they’ll see Venus crossing the Sun in two slightly different paths. The distance between those paths, if you know how many miles apart the observers are, can then be translated into how many miles away Venus is from us and from the Sun.
Thus, to measure the parallax of Venus you have to have at least two observers in well-mapped positions, as far as possible from each other. Getting to distant locations and measuring their positions accurately was in itself was a challenge in the 18th century. The more people observing, the better you could average out these uncertainties. By the middle of the century, an international group of astronomers were preparing the observations.
Unfortunately, they didn’t count on the vagaries of international politics. By the 1761 transit, France and Britain were engaged in the Seven Years War, raging from India to North America. When the Astronomer Royal’s assistant, Charles Mason, left for India he never got farther than the English Channel before being attacked by the French fleet. (His ship escaped back to England, and eventually he sailed to South Africa.) Likewise, the French astronomer Le Gentil got to India only to find that his goal, the French colony at Pondicherry, had fallen to the English; on the day of the transit, his boat was still out at sea, for fear of capture.
With all these difficulties, and the challenge of observing a very dark spot against a very bright Sun, the results of the first set of observations were less than satisfactory.
It was another eight years before a second set of observations could be made. Mason and his surveyor assistant, Jeremiah Dixon, came home by way of the North America colonies, where they took the time to survey the boundary between the northern and southern (slave-holding) American colonies, known to this day as the Mason-Dixon line. Le Gentil stayed in India to wait out the next event. And, after the end of the war, the Royal Astronomer decided to lease a ship, the Endeavour, from the Royal Navy for the next expedition to the South Seas.
The 1769 event was observed at 77 different locations around the world. Le Gentil, in India, saw nothing but clouds; having missed both events, he returned to France only to find that he’d been declared dead and his property distributed among his heirs. But other observers (including Jesuits in China and an arctic expedition lead by Fr. Maximillian Hell of Vienna) had greater success. The results were surprising: the solar system turned out to be some ten times bigger than most astronomers had expected.
The astronomical significance of this measurement did not stop at the solar system. Knowing how far the Earth travels as it goes around the Sun allows you to use the same parallax trick; the positions of nearby stars appear to move ever so slightly compared to more distant stars when observed from one side of the Earth’s orbit to the other. In this way, distances to stars could be measured, and the scale of the galaxy determined. This was the first step in calculating the distance to other galaxies, and clusters of galaxies, a measurement that forms an active part of astronomy even today. It’s a big, empty universe out there.
The success of the 1769 observations had other ramifications. The young Navy lieutenant assigned to keep an eye on the Endeavour -- James Cook -- started a tradition of combined naval and scientific exploration of distant seas, from Australia to Hawaii, which foreshadowed Darwin and the Beagle and indeed the military pilots who flew the Apollo missions to the Moon.
Today, spacecraft make these measurements far more accurately. But anyone equipped to look at the Sun can recreate those historical observations. (Use all the same care you'd use for a solar eclipse, as in 1999: proper filters, or pinhole projection. Don't look directly at the Sun, and don't look too long even with filters -- stop before it hurts!)
Take a moment on the morning of June 8 to appreciate this rare dance of the planets. There is a peculiarly human delight at predicting and seeing this conjunction, and knowing its historical and scientific significance. As Sting sang: there’s a little black spot on the Sun today; that’s my soul up there.
The transit in 2004 was observed from our rooftop in Castel Gandolfo with a group sponsored by Sky and Telescope. The 2012 transit was observed there by our Vatican Observatory Summer School
Transit observers from the Sky and Telescope group of 2004, on the roof of the Papal Palace