Jul 072015
 

Celestial-BuddiesA week from today, the NASA New Horizons Spacecraft will perform its close flyby of Pluto, beaming back the first color images of our solar system’s last uncharted world (and finally telling the makers of the Celestial Buddies line what color they should make their long-awaited cuddly Pluto). In celebration of the occasion, I have solicited a guest post from my good friend Jonathan Sneed, an astrogeologist/ paleobiologist, currently working as a research technician with the Solar System and Exoplanet Habitability Group here at the University of Chicago. Jonathan studies rocks, and what rocks tell us about how planets and other astronomical bodies form and develop, especially when life gets in the mix. These are the skills we need to predict which planets and other space rocks might have life, or the chemicals necessary to support us as we launch out into the vast and black frontier.  Jonathan’s essay offers predictions about what New Horizons might find when it makes its flyby next week, gives a taste of how much photos alone can teach us about the history and potential of Pluto, and offers a glimpse of how astrogeology lets us learn about the celestial stepping stones scattered around us.

_______________________________________________________________________________________________

So, Pluto.

When she’s talking about the history of skepticism, our host likes to talk about Pluto, and in particular about the argument that scientists had about it.  Shall it be a planet?  A dwarf planet?  A planetoid?  Megarock?  Especially large ice cube?  In her classroom, Pluto is the enemy of eudaimonia, a didactic example of the stress we experience when our perceptions shift and the maps are all rewritten.  She discusses the ways that we use doubt to insulate ourselves against collisions between truth and belief, how the ancient Pyrrhonists found a refuge in uncertainty.  It’s all rather grim.

Obviously, I can’t let her be the one to talk about the imminent New Horizons flyby.

It is, after all, a unique moment in human history!  For most of us, most of the time, discovery is a kind of communication.  You turn to page 57 and look at a full-page spread of the Krebs Cycle, or stop by a street performer on your way to the grocery store and hear real jazz for the first time, or open your RSS feed and read a quote by Sartre, and your world shifts under your feet just a bit.  But moments like this are a reminder: there are things that nobody knows, and you have the ability to know them.  If you’re willing to admit a little uncertainty, that is.

Over the next few weeks, a great many things will become known about a whole new world.  I thought this might be a good opportunity to sketch out some of what you might look for, so that you can participate a little bit more actively in that moment, if you have a mind to do so.  The New Horizons craft is outfitted almost entirely with cameras, imagers, and spectrometers of one sort or another, so we’ll have basically one thing to go on: what color is it?

Granted, some of those photons will be well outside the range of the human eye, so I’m using ‘color’ with a certain amount of poetic license.  But at the end of the day, it’s a remarkably straightforward little device.  We were curious about Pluto, so we looked at it.  The atmosphere should be quite visible, and it’s more than thin enough for us to peer through that atmosphere to the solid surface beneath.  From there, we’ll see not just the elements that make up pluto, but also the chemical arrangements that they’ve made for themselves and the large shapes and geological formations that have emerged.  Are there mountains and valleys?  Volcanoes?  Some kind of erosional process that cycles and recycles the surface?

And these things, in turn, will tell us more than you might expect.  Because we don’t just know what Pluto looks like now; we have a pretty good guess about where it started, and two points make a line.

Above: the old black & white photographic plates from which we discovered Pluto.

Origins:

One of my favorite facts (up there with ‘birds are dinosaurs’) is that the number of mineral types in the universe is increasing at an exponential rate.  For a geologist, every day is the most exciting day the universe has ever had!  A while back, the first stars and the preposterous forces at work inside them, gave us the first heavy elements and the few mineral grains they can form drifting in interstellar space.  Eventually, those first primitive grains clumped together to form rocks and then whole planets, with solid bits and fluid bits and change, and new minerals emerged from that dynamism.  The kind of minerals that are only formed when water evaporates into an atmosphere and leaves a residue behind.  The kind that are only formed when some kind of fancy-pants self-sustaining carbon-based chemical process decides to secrete a shell for itself.  The kind that first come in to being when a state legislature settles on new safety standards for concrete.  And so on, accelerating ever onwards.

(Actually, human-created objects don’t technically count as minerals, but this is an arbitrary semantic line. ‘Anthropocite’ is far too wonderful a word to not get used in a scientific journal eventually.)

What this means for Pluto is that, despite the huge variety of things that a (dwarf) planet(oid) might do, the starting ingredients have to be drawn from a set of things that can be cooked by a star and are willing to clump together in space.  As to what it did with those things in the four and a half billion years since… well, that’s harder to guess.  But here are some of the most important  ingredients that might go into your Pluto recipe, drawn straight from the primordial dust itself:

Water ice.  Ammonia.  Silicates, with a variety of elements thrown in for flavor- potassium, phosphorous, a great many metals.  Iron and sulfur compounds, usually bonded with oxygen or mixed in with the silicates.  Carbon, doing its crazed carbon dance, probably already forming a few amino acids and alcohols as it falls into the gravity well.  Carbon, being less creative, oxidized or in the form of methane.  Hydrogen and helium, as much as you like, although those will run away from the world almost as soon as they arrive.

Not Pluto yet, but could be some day.

I’ve been careful to emphasize some of the ones that I think are going to be important, so this is isn’t comprehensive.  But it’s a lot closer to comprehensive than you’d think.  All in all, there are a little more than a hundred different molecules floating around between the stars, a shockingly finite list.

Even more conveniently, we have a category we can use.  No, not ‘planet’, alas.  The category I am thinking of is ‘Kuiper Object’.  On Ex Urbe, categories are a deep and compelling subject in their own right, but for the time being I shall take a narrow and cowardly view.  All I mean is that Pluto is quite similar to a lot of other things in the ways we have already measured, and so I wouldn’t be too surprised if it was also similar to those things when we measure new aspects of it.

Kuiper Objects are a fascinating bunch, named by the region just outside Neptune’s orbit.  They’re quite icy (some would even float), and they come in a range of exciting colors for the discriminating consumer (gray is common, and red and black are, as always, favorites).  There are many things we don’t know about Kuiper objects, but we’ve also had one tantalizing opportunity:

Not Pluto, but might be Pluto on a higher hypostasis.

This is a picture of Triton, one of the moons of Neptune, given to us by interstellar traveler and Blind Willie Johnson fan Voyager II.  Triton is quite icy, although it would not quite float in water.  It comes in a range of exciting colors, primarily gray and red.  And it’s going around Neptune in basically the wrong direction, which implies that it fell into Neptune’s gravity well a good deal after planetary formation.  It also, for the record, has an atmosphere, surface composition, and density shockingly similar to that which we infer for Pluto.  So, there’s that.

Motion:

A while back, I shared an office with a guy who wrote a thesis about how confusing Kuiper Objects are.  He had written an efficient and cutting-edge program that would transform reasonable assumptions into arcane squiggles and crying graduate students.  I learned a lot from that guy, especially about the perils of trying to predict the behavior of (dwarf) planet(oid)s given even very simple starting conditions.  What happens when you make a very, very large pile of ice and silicates, and then wait for four and a half billion years?  What do we expect to see when we take our picture of Pluto?  Potentially, a lot of things.

But for any big pile of rocks, there are basically four ways to get the thing to move: sunlight, radiation, gravity, and chemistry.  Actually, gravity and radiation make a nice twofer.

The idea is this: shuffle silicate rocks and water ice into a big ball.  A lot of the heavier metals mixed in with your silicates are a bit radioactive, so they warm the ice around them into a kind of slush (same reason the Earth is a fluid once you go a few miles down).  That’s just enough lubrication to let the heavy stuff fall to the bottom, and the lighter stuff rise to the top- and now we have some density gradients to work with, and maybe even some liquid(ish) water.  Even more excitingly, everything in that ball that isn’t easily trapped in mineral form (the nitrogen compounds, the methane, and all those wonderful mad organic molecules) will tend to get squeezed out to the exterior surface, or near it.  We call those ‘volatiles’, which is one of those charmingly literal phrases that scientists sometimes use.  They explode, is what I’m saying.

Almost certainly, this is the process that first set Pluto in motion.  But what happens then, especially on the surface? Once you squirt out all the gasses and form an atmosphere, and expose your wiggly mad carbon to sunlight, what does it do next?  Well, here’s where the graduate students start crying, but let’s give it a shot.  We’ll start with the most sensible and least speculative feature, giant ice volcanoes.

The plumes of Enceladus are not Pluto, but are a good example of cryovolcanics.  I did say ‘volatile’.

Ice volcanoes are a good sign of an active world, for the same reason that molten rock volcanoes are on Earth- they have to be refreshed by ongoing tectonic activity.  As far as we know, they’re exactly the same kind of structure.  At temperatures this low, ice is just another kind of rock, and it takes geological forces to warm that rock up to its melting point and expel it as magma.  Except, the magma is water (plus a complicated mix of other volatiles like nitrogen)- so we call it ‘cryomagma’, a truly fabulous word if ever I saw one.

If we’re exceptionally lucky, we’ll see an active volcano during the flyby- on Triton, our closest analogue to Pluto, these eruptions can last for (Earth-) years, so it’s not an unreasonable hope.  But even if we don’t, we should be able to find strong evidence that they did happen; look for dark smears in the calderas as frozen nitrogen ‘ash’ falls back to the surface.

Another really important thing to watch out for is the craters.  Specifically, there not being any.

Here’s a puzzle for you: how do we date rocks on Mars?  If you’re lucky enough to have a rover right there, you can run any number of exciting tests, but it’s a big planet and there aren’t that many rovers.  Yet, we have guesses about the age of Olympus Mons and Hellas Planitia.  How?

The answer is that Mars is fairly inert- enough so that the craters are more or less permanent fixtures.  So if you know how often a meteorite is going to blow a hole in a given area, all you have to do is count the craters and then you have a pretty good measure of how long that surface has been exposed.  ‘Pretty good’ means plus or minus 600,000,000 years, granted.  But I think it’s a pretty cool trick anyway.

Mars is also not Pluto. By my calculations, this surface originates on August 5th, give or take the entire duration of multicellular life in the universe.

So if we make it to Pluto and it’s covered in craters like Earth’s moon or Mars, then that means Pluto has slowed down a lot in the last few billion years.  If, on the other hand, it’s fairly crater-free, then something is busy removing those craters.  That smells quite a bit like active tectonics.  So: ice volcanoes, or craters, but not both- those tools could give us a pretty good idea of whether there is an active mantle in the subsurface, pushing the outer (nitrogen, methane, ice) crust around and otherwise being interesting.

Only, that mantle would be a fluid made of, among other things, water.

Chemistry:

As a species, we’ve gotten very good at looking, so even before New Horizons we knew a few things about the surface of Pluto.  Broadly, it has the coloring we expect for a Kuiper Object: grey, black, and red, and is sharply mottled.  But what, actually, do these colors mean?

I mentioned sunlight as one of the forces that must move Pluto.  Granted, the sun lacks a certain degree of strength at that distance, but in combination with the rotation of the (dwarf) planet(oid), the sun is going to be the primary cause of temperature variations at the surface, far away from all that radioactive rock at the center.  As the ice volcanoes have shown us, it’s not so much the absolute temperature that matters, as whether or not that temperature cycles around any interesting phase transitions.  And as it happens, there are three (and only three, that I know of) materials in our original Pluto recipe that have an interesting phase transition at Pluto’s surface temperatures: carbon monoxide, methane, and nitrogen.

This blackened and mottled carbon is not the surface of Pluto, but it does share many interesting chemical properties.

These can have seasonal rhythms, they can precipitate or frost, and are generally going to provide a lot of the bulk material for all the really interesting chemical reactions at the surface.  If the ice of Pluto is as rock on Earth, then these are its water and air.

Nitrogen doesn’t help us with that coloration problem too much, but the other two?  Those are interesting.  Because the beating heart of both is a bit of carbon, and carbon is flexible enough to explain a great many things and a great many colors.  This is the element that gives us black graphite and transparent diamonds, after all.  When our carbon molecules are left outside for a few billion years of exposure, through years of those interesting phase transitions, something will change- the carbon will fry in the ultraviolet light.  Very, very slowly, and it has to be peeled away from the hydrogen and oxygen first, but it will fry all the same.  And as it happens, this can explain both the red and the black against a grey ice background.

 

Ceci n’est pas une Pluto.

These are not, of course, the only explanations for the colors that we see on the surface of Pluto.  Red has a classic association with iron oxides (you and Mars are red for the same reason, as it happens), and there is a potential universe out there where the surface of Pluto is rusted.  But the world is not very dense, and so this would require a great many odd things- not only that there be no mantle fluidity to pull dense minerals inward, but that some inverse process pulled it away, concentrating that metal on the outer circumference.  I can’t think of what that might be.  But nonetheless, it could be what reality gives us.  The disadvantage of this theory is not that it is impossible, just that it requires a great many things to be true.  And so I lean towards an explanation that doesn’t demand further concessions from reality, using only the processes that we already acknowledge on the parts that we started with.

Carbon and Water:

I have done a mean thing.  I used cryovolcanics and an analogy to Triton as a way of suggesting that there might still be liquid (or at least slushy) water on Pluto.  And then, I invoked a reasonably elegant explanation of Pluto’s mottled coloration to suggest that surface processes are driving chemistry of complex carbon molecules.

You are now thinking about aliens.

Or at least, I assume so.  I would be.  Not flying saucers or anything out of our drive-through horror shows.  No, you’re considering the possibility of some simple microbe, maybe a Plutonian lichen of some sort, with subtle but radical implications for our role in the universe as living things.  Then again, maybe not; I spend a lot of time thinking about aliens, so my calibration may be off.  But if you were thinking about aliens, I apologize.  There are not aliens on Pluto.  Definitely not, certainly not.  I am at least 95% sure, and even that is rounding down.  Probably.

There’s a funny inverse to the eudaimonia of skepticism.  If we remember that anything we believe might be false, then we can indeed let go of our beliefs with a certain grace.  But if anything might be false, then just think of all the things that might be true!  And there’s the danger.  Before long, we look up and see the canals on Mars that we hope for, rather than the Vallis Marineris as it actually is.

Every planet and moon that we’ve investigated in this solar system has been utterly unique.  These worlds are awesome, and frightening, and alien.  Crystal cities on Venus would have been amazing, but they would have been amazing in a very human way- they would have been our fantasy, not an encounter with a genuinely new reality.  And in the same way, whatever is really on Pluto, it’s going to be an experience that wasn’t bent to fit our expectations, a thing that nobody knows.  It will be wonderful, even though it won’t be life.

Probably.

Pluto, viewed by New Horizons on approach.

______________________________________________________________________________________

I hope you will join me in thanking Jonathan for this delightful contribution! -Ada

Apr 272013
 

Note: this is a guest post.  I am on another research jaunt, speaking in Rome and Oxford and visiting an intriguing book in Paris.  While I’m travel-swamped, a good friend, Rush-That-Speaks, has agreed to write a guest post, describing a little Roman adventure we shared.

Rush-That-Speaks writes:

The last time “Ex Urbe” and I were in Rome together, which was late in November of 2011, we were sitting in our hotel room one moderately tired evening, and, as one does, were discussing the Borgias. I believe that this was in the context initially of the Borgia arms, which are stamped on everything the family sponsored in Rome during Rodrigo’s papacy (1492-1503). The coat of arms of the reigning pope also gets put up at all the churches where the pope is a regular celebrant, and not taken down no matter how many centuries go by, and sometimes popes just put their arms up on things because they’re pope and they can and it’s a Statement. The Borgia bull, therefore, is pretty common throughout the City, along with various other Renaissance great houses who at some point took the papacy: Medici and della Rovere and so on. Honestly these tend to be in better taste than more recent stamps-of-arms; Benedict’s arms came out a rather nasty shade of fuchsia. So we were talking about places we’d spotted the bull that day, surprising and otherwise, and how annoying it is that Cesare Borgia is buried over in Spain where people who have been traveling through all the scenes of his life in Italy cannot easily go and look at him.  [Ex Urbe Note: Reminder regarding Cesare’s tomb, he was originally buried in the Church of Santa Maria in Viana but in 1537 the bishop had the tomb destroyed and his remains buried in unconsecrated ground, as (many thought at the time) such sinful monsters deserve. In 2007, on the 500th anniversary of his death, the Archbishop currently in charge of the site had Cesare dug up and moved back into a proper tomb again, partly on the theory that 500 years’ exile was enough even for such a monster, and because it was a publicity and tourism coup.  Lucrezia is in the castle in Ferrara with her last husband, Alfonso d’Este]

The Tomb of Alexander VI, nominee for Worst Pope. But where is it?

Which led to contemplation of the death of Cesare Borgia, purulent with syphilis and defeated but still fighting as he was, and then to the anecdote about the seven devils who came to Rodrigo Borgia’s deathbed to bear him off when his time for plaguing the world was finished (a fairly well-accepted bit of gossip); and then a question occurred which had never really crossed either of our minds before, namely, if Cesare is off in Spain, then where is Rodrigo Borgia buried?

If you want a papal tomb of course you traditionally look in St. Peter’s. He wouldn’t be in the upper level, the church itself, because you have to be a saint or at least beatified to be buried in that part at all. Many popes who have not yet achieved sainthood but hope for it are buried in hopeful little tombs in the basement crypts, and then whenever one of them is exalted in status he is moved upstairs and showered in triumphant statuary. But it’s not as though there’s a morals requirement for being buried in the basement. Boniface VIII is down there, the pope Dante spent several cantos calling the Antichrist, and Boniface is even buried with his nephew, the one whose appointment as Cardinal gives us the word ‘nepotism’, from nepos, nephew.

However, if Rodrigo were in the basement of St. Peter’s either “Ex Urbe” or myself would have heard about it at some point. St. Peter’s is a very heavily documented and famous place, discussed by artists and architects throughout history. There are explanatory books and pamphlets about it sold maybe every fifty feet in the City of Rome, there are guided tours, there are non-guided tours, and at some point in some way one of us would have come across the fact of him if he were in there, even if he were in a portion never open to the public.

Ex Urbe note: Popular historical figures in Rome receive frequent visits, flowers and letters. Here is what collected at the foot of a modern statue of Julius Caesar near the forum, while other flowers appear (the and throughout the year) at his tomb, and at the spot where he was killed. Cities, nations, clubs and organizations leave big wreathes, while many individuals just contribute a single blossom. I often do too when in town on the ides, and get a special thrill seeing how many others are so moved by history.

So we looked it up. Rodrigo Borgia is buried in Santa Maria in Monserrato degli Spagnoli, the Church of Holy Mary in Monserrat of the Spaniards, which is the official Spanish church in Rome. By this I mean it is the church in which Spanish dignitaries in Rome conduct their ceremonies, and the church which is specially charged to look after Spanish travelers in distress, and, most importantly, where famous Spaniards who die in Rome are buried. Many countries have such churches in Rome, and so do several professions– the official sailors’ church in Rome is very close to S. Maria in Monserrato, and so is the official Russian church (a more surprising object). It is not, however, a very prestigious place to be buried, not if you are a Pope. The reason why is tomb desecration: people kept trying it. They’d put Rodrigo in one place, and someone would desecrate the site, and then they’d move him, and it would happen again, and it just kept happening, so they moved Rodrigo and the previous Borgia Pope, Callixtus III, who was somewhat better liked, into the Spanish church. And didn’t mark the place. And buried them together. And hoped that would do it.  [Note from Ex Urbe: There are reports of Alexander’s immediate successors, especially Julius II, refusing to let him be in St. Peter’s, and Julius even ordered that all Borgia tombs be opened, but the vandalism seems to have been not only fast but also frequent and consistent over decades.]

It’s marked now, because in the middle nineteenth century a fairly popular King of Spain died in Rome, and when they buried Alonzo XIII next to the Borgias they figured they’d better put up a mausoleum so everybody knew who was where. The body of the King of Spain has since been repatriated, but apparently no one is angry enough to desecrate a Borgia tomb anymore, so the plaque for Rodrigo and Callixtus remains.

This meant we could go over and leave Rodrigo some flowers. I was curious to see whether anybody else would have.

We started by going over to the Campo de’ Fiori, which is the flower market of Rome. It’s also an open-air market for a lot of other things, the usual tourist souvenirs but also a very good produce and farmers’ market with a wide selection of seasonal fruits and vegetables in the early mornings, and in the center it has the monument to Giordano Bruno on the spot where he was burned at the stake for heresy. A thing it is pleasant to do, and which I had done earlier in the trip, is to buy fruit from the market, such as one of the kaki, the big sweet orange Italian persimmons, and sit on Bruno’s plinth and eat it looking at him. He is usually covered in pigeons, as are many statues in Rome, but he looks less indignant about it than most of them. But that day we had to figure out what kind of flower you take to the grave of Seriously The Most Evil Pope. The flower market is not seasonally restricted the way the rest of the market is, and is basically open-air florist’s shops, so you can really get just about anything. An orchid might be overdoing it a little? What seemed most appropriate was a single dark red rose, though in the end a small cluster of coral-colored roses was the best we could acquire.

Then to find the church. It is not easy to find a single church in Rome. Any given block will have between two and five of them. The internet told us that S. Maria in Monserrato was on a street called the Via Giulia, pretty much due west of the Campo de’ Fiori, south of the Corso Vittorio Emanuele and south-east of the Mazzini bridge. The Via Giulia is a fairly long street, running north-west to south-east, in a quiet little quarter between Everything Historic and the river. We found the street itself pretty easily, and it turns out to be a sheltered backwater of a neighborhood, somewhat residential but mostly centered on antique shops and obscure churches of precisely the sort we were looking for. We went into several antique shops, as “Ex Urbe” is on a years’-long quest for an affordable piece of porphyry, and the thing I will never quite forget about the Via Giulia was the way every single antique shop reeked desperately of a different flavor of incredibly penetrating cigarette smoke. It was astonishing. I would have been afraid to buy stone tablets from some of those places for fear of the smell having seeped into solid rock. But the owners were friendly and knowledgeable and good at their professions, which means of course that there was no affordable porphyry, because no one good at the profession of antiquing would permit such a thing to happen.  [Ex Urbe note: had I been 900 euros richer, I might have left one shop 900 euros poorer with the most beautiful marble tile inlaid with spiraling triangular chips porphyry and serpentine… I can still see it if I close my eyes… just like the Sistine Chapel floor.  Have I griped recently about how hard it is to find a photo of the Sistine Chapel floor?]

Part of Via Giulia was under construction that day, so Rome, in good spirit, covered the construction wall with images of Renaissance ladies’ costumes.

There were also signs up and down the Via Giulia talking about celebrating the neighborhood, and the artistic and antique beauty of the quarter and its long history, and these signs had on them a portrait of… could it be? Does irony work in such mysterious ways? Was Rodrigo Borgia, Alexander VI, The Most Evil Renaissance Pope, really buried on a street named for Pope Julius II, Giuliano della Rovere, Rodrigo’s successor to the papacy and rival, enemy and heir? Della Rovere who fled to France when Rodrigo was elected, for fear of poison, della Rovere who brought Charles VIII of France back with him to conquer Italy, so mad was he to see it taken from the Borgias? (It didn’t work. Rodrigo bought the right people in the King of France’s cabinet: Charles conquered, but did not depose the papacy.) Via Giulia. There was his picture on every signpost banner. How remarkable.

Except of course that we couldn’t find the church anywhere. As I mentioned, the street is a long one, and we went up and down it two or three times, from the Official Church Of The Florentines In Rome at one end of it to the bit where it peters vaguely out near the river at the other end. [Ex Urbe note: of course Florentines need their own Church in Rome: S.P.Q.F!] There are a lot of little churches, all with similar facades, white and severe with the same kinds of inset columns, the same triangular pediments, the names carved neatly into the marble somewhere or other, but no facade that matched the one we’d seen on the internet, and no remotely similar name. It was beginning to get late, on a November evening which was starting to aim for freezing, and the first few people we asked had no idea either.

It was an antique-shop owner who told us, finally, that of course Via Giulia as the address of the church didn’t mean it fronted on the Via Giulia; it has its unmarked back to that street. No, it fronts on the Via Monserrato, one street easterly, and we’d walked by the back at least four times. We located it, and there indeed it sat, the white facade, the inset columns, the neat blank triangle pediment, the carved correct name, and the sign on the door saying that it is open only for Masses at seven and nine a.m. Sundays.

The interior of the church where Alexander is buried. Given that it’s a Spanish-run church, readers should be able to Spot the Saint in the painting toward the left, even blurred and from this distance.

This is not actually that uncommon a situation with churches in Italy. They do not always enjoy being treated as art objects and goals for a tourist tramp. They are part of a living religion and tradition and would like that respected, and also they haven’t got the manpower to keep everything open all the time, because there are just too many churches for that to be possible. A small, obscure church might only be open for Mass on its saints’-day, or every other Sunday, or every third week, or whenever it is part of the rounds of the local bishop, maybe every few months. Open every Sunday actually indicates that S. Maria in Monserrato has a devoted and habitual congregation, quite possibly composed of the expatriate Spaniard community for whom it was originally built. We had had to give up all hope of seeing the grill of St. Lawrence earlier in the trip, because the church where that is kept opens once a year officially and we couldn’t figure out what door nearby it might lead to someone with the ability to let us in. There’s a church with a Michelangelo in it in Florence which is practically a landmark because of the crowds of tourists standing around it trying to figure out why it is inexplicably closed all the time; “Ex Urbe”’s lived in Florence for more than one year of her life and never gotten in there, and no helpful signs, either.  [Ex Urbe note: Someday I will be there on Good Friday, when ALL Churches are required to open their doors to everyone. Then I will go in and perniciously look at all the art!  Wahaha!  Wahahahaha!]

But fortunately, we had tramped out to find Rodrigo Borgia on a Saturday afternoon, and Sunday lay before us. So we hauled ourselves out of bed on Sunday morning, and were at the church doors just before nine a.m., and they were open.

Now, any Mass at a church of this sort is open to anybody, but it is rude to hang around for very long if you are not actually going to go to the service, and it is very rude to wander around a lot taking pictures and gawking and then leave visibly. We did not even go up to the front. There may well be some decent statuary or painting in there somewhere, but we did not see it, because we went straight to the Borgia tomb, which luckily is in the first niche on the right-hand side, and stayed there, out of the way of the entering crowd. There’s a railing keeping you out of the actual niche, and the tomb itself is well back in the niche, in the right-hand-side wall, so in order to see it you have to stand with your back to the front of the church (and the altar) and crane your neck over, which seems appropriate. It’s a chaste enough marble tomb, done up like a little Greek temple, with relief busts of Rodrigo and Callixtus and a model stone pope hat, the Borgia bull three times and no motto. The tomb of the Spanish king, which is under it, is very much more mourning-centered and has a motto about how much his people loved him; I am pretty sure the contrast was intentional.

A terrible pope, yes, but, with the luxury of distance, an historian can’t help but be fond of him for giving us such interesting times to study. He deserves the occasional visit, even if the old half-Spanish roman ladies who had turned up for mass stared at us suspiciously.  Can’t blame them – I’d stare suspiciously at someone who brought flowers to Borgias.

“Ex Urbe” is taller than I am and has better aim, so she leaned over the railing at an angle and then tossed the rose. It landed well, on the floor in front of the tomb. There weren’t any other flowers in sight. We slipped out of the church just as the doors were shutting and Mass was about to start, blinking into the bright morning. Speculating over whether, when they came to clean the niches, the staff would think the rose was for the King of Spain, and whether this happens often. I somehow think it doesn’t.

So Rodrigo is buried facing the Via Giulia, and the church he’s in is facing away from it, but also actually on it. This is very much the way the City of Rome turns out to work, sometimes. Like how Caesar was stabbed on the messiest junction of the overground tram tracks, a gentle and unmarked unintentional joke upon history. I am not entirely certain it is worth going out of your way for his tomb, as a tourist, unless you are the way we are about the Borgias and happen to have a free Sunday morning, but it was certainly worth it to us, and the option is there for those who may want it.

(Rush-That-Speaks writes book reviews of sci-fi and fantasy literature, and blogs about many things including reading an impressive range of books, a lot of genre topics.  She recently completed a project to read 365 books in 365 days, a fascinating and impressive undertaking.  You can find her own blog here, or hosted through LiveJournal.)

Related: Read about the Borgias in TV Drama.