Wednesday, August 15, 2018

Buon ferragosto!

Statue of Mary in the papal gardens, a favorite spot for Popes
to pray.

It's the Feast of the Assumption, a holy day of obligation in the US and of course, here in Italy. Here, however, it is also a major holiday - ferragosto. Stores are closed, many for the whole week.  Even the supermarket with 'orario continuato' — continuous open hours, they don't close for the mid-afternoon rest — is closed today.  You could definitely feel the anticipation in the air yesterday afternoon as people ran last errands around town.  Me, too.  I bought melon and tomatoes and herbs from the farmer's market in the square and some salumi at the supermercato. Everyone was wishing each other a cheery "Buon ferragosto!" 

Bit of mosaic in floor at San Pietro.
This morning when the bells from San Pietro started to ring at 8 to nudge people planning on going to the 8:30, I grabbed my bag and headed out to church. It's a two minute walk to this 6th century church, named for St. Peter the Apostle (who apparently evangelized the Romans living here back in the day). The church was already half full, the Eucharist is on the altar almost all day for those who want to come in and sit.  I sat.  Mass at 8:30 was full, but I should have paid attention to the seating pattern. Sit nearest the open door that overlooks the plain below. The breeze is delightful, as I discovered when I went up to communion.

San Pietro after Mass. The sisters are in the 
prime spot.
There is a clear sense of celebration in the town. Local restaurants are doing a set "ferragosto" menu and I went out with the Jesuit community here across the square for a two-hour pranzo, the main meal of the day.  Pace yourself, I was warned. Two types of antipasti, bread, wine, water, lasagna al forno, crispy calamari and shrimp. Another pasta and fish dish: paccheri di scoglio. That last translates literally as "slaps of rocks" - actually pasta with clams, shrimp and mussels in the shell; paccheri is large tubes of pasta that apparently make a slapping noise when they hit the plate. Finally, watermelon for dessert and an espresso so you don't (quite) fall asleep at the table.

I went back to the apartment to change for my afternoon walk, dodging kids with squirt guns and enjoying watching the women of my age dressed in their best out walking. I don't have the panache to wear some of the shoes (or the willingness to risk my ankles) - so much gold lame and so many glittery sequins. Though you have to admit, it absolutely goes with the feast:  Risplende la regina, Signore, alla tua destra. (or in the US, The queen stands at your right hand, arrayed in gold.)

Now, of course, it's afternoon thunderstorms, so I'm waiting it out, the local weather suggests we'll get a break soon.  Meanwhile, the papal roosters are annoyed at the changing light, the thunder and the ringing bells to announce Mass at one of the five churches within a few minutes walk. They are crowing up a storm!

Sunday, August 12, 2018

Do you believe in miracles? Santa Maria on the way

The skull of St. Agnes is behind the small 
green circle of leaves above the tabernacle.
It was hot, hot, hot and humid in Rome yesterday. I took an early train into Rome from Albano, having finished up a couple of significant writing projects the day before and having checked on the weather, which suggested it was only going to get hotter over the weekend.

When I got off the Metro at Spagna just before ten in the morning, I was struck by how empty the piazza at the bottom of the Spanish steps was. After the bustle of Termini station, it was so deserted it was eerie.  As I walked across the middle of the empty plaza, feeling like I walked into a Fellini film,  I suddenly understood why there was no one else there.  The sun was already high enough for the entire center to be in the full sun, with the heat radiating off the black basalt Sampietrini pavement. In the two minutes it took me to cross I was drenched in sweat and wishing I'd had the sense to pop up my Japanese umbrella/sunshade.

An actual dome in Sant'Ignazio.
I meandered my way from the Spanish steps to Piazza Navona and back again, walking nearly 9 miles as I did so.  I had back-to-school shopping to do along the via del Corso, mostly shirts and pants for the guys.  I ducked into various churches over the course of the day - a miniature pilgrimage as a counterpoint to the shopping.  I lingered in Sant'Ignazio with its faux dome, prayed in Sant'Agnese in Agone, which has a magnificent dome which you are NOT allowed to photograph, but where the attraction for me is a closet-sized Eucharistic chapel in the back with the skull of the martyr in the altar for all to see.  At the end of the day, walking down one of Rome's serpentine alleyways, I was suddenly confronted by a trumpeting angel, bearing down on me from the roof of Sant' Antonio dei Portoghesi, into which I took an unplanned peek. A baroque jumble screamed at me as I walked through the door.  I back right out again.

Sant' Antonio dei Portoghesi
I hadn't planned on a visit to Santa Maria in Via — Mary of the way — either, but ducked in on a whim.  Built in the late 15th century and completed under Cardinal Robert Bellarmine, SJ in the 17th century, it sits on the site of a miraculous well. The story is told that on a September night in 1256, the well in the stables of Cardinal Pietro Capocci's residence overflowed.  An icon of Mary imprinted on a tile was found floating atop the waters.  Pope Alexander IV promptly ordered a chapel built over the top of the well. [Bonus - today is the feast of St. Clare, who was canonized by Pope Alexander IV.]

The church is full of anachronisms.  There is a Caravaggio tucked into the corner of a side chapel, in a spot so dark I could not make out the subject (the sign on the altar rail is the only way I knew the artist — and I can't find any such painting on the list of the Caravaggio's in Rome, I'll have to go back and double check).  Why is there an enormous teleprompter stuffed into yet another side chapel?  And the plumbing for the miraculous well would not be out of place in a fancy wet bar.

The holy well in Santa Maria in via, you can see the sink and
the faucet on the right hand side where the young man is 
filling up a cup, just like at the coffee bar.
Yes, the well is still there, and cups are set out for the steady stream of people who want to drink from the miraculous water.  I now have a bottle of this holy water for a friend, and another bit to take home.

I wonder if anoint my aching ankle and foot in the water from the well, it will be healed. I'm almost afraid to do so.  If it improves, will that increase my faith (the point of miracles.) I don't think so.  It it doesn't get better, then what?  I still believe.

I'm sorely tempted to make the holy water into a holy ice cube and ice my foot. That will definitely make it feel better, and to the people of Bellarmine's Rome, would look as much a miracle as the floating tile did. But I suspect that is cheating.
Seen in the window of some very chic
shop by the  Spanish steps.
Ankle or no, I adored these flaming shoes. Just what I need to lecture about thermodynamics in. They'd be perfect for the combustion of organic compounds lab — except of course, no open toed shoes in the lab!  Pink or black? Black, I imagine!

Wednesday, August 08, 2018

Ghosts of elements, spectres of the universe: Angelo Secchi SJ's stellar spectra

A plate of Secchi's spectra.

This year marks the 200th anniversary of the birth of astronomer Angelo Secchi, SJ, the pioneer behind stellar spectroscopy, which opened the door to our understanding of what makes up a star.  I'm spending a couple of weeks at the Specola Vaticana outside Rome, of which Secchi is arguably one of its founders, though the official founding of the current incarnation of the Specola would come nearly 15 years after his death.

[A version of this post is cross posted at the Vatican Observatory Foundation blog, The Catholic Astronomer]

If you’ve seen the flash of yellow-orange flames when a pot boils over on a gas stove, you’ve gotten a glimpse of the ghost of an atom, specifically sodium.  The color is part of the atom’s spectrum, which shows which types or frequencies of light are absorbed by that particular atom.

In the late 17th century, Isaac Newton used the Latin word for ghost, spectrum, to describe the bands of colors he saw when light shone through a prism. In 1814 Joseph von Fraunhofer noticed he could see bright lines instead of the bands of colors when looking at certain flames through a prism.  He went on to develop an instrument to measure these spectral lines, called a spectroscope.

Fraunhofer noticed a series of missing colors, dark lines, when looking at the sun’s light through the spectroscope, and went on to characterize the light from several stars as well.  Fifty years later  Jesuit polymath Angelo Secchi invented a series of spectroscopic instruments specifically for examining the patterns of colors in the light from stars and the sun and used it to build a catalog of more than 4000 stars.  Secchi classified the stars by recurring patterns in the light, which were a clue to the star’s composition.

Around the same time Secchi was building his catalog of stellar spectra, Gustav Kirchhoff and Robert Bunsen (the inventor of the ubiquitous Bunsen burner) were involved in a more down-to-earth scheme. Kirchhoff and Bunsen teamed up to create a spectroscope that used Bunsen’s new hotter, gas burner to ignite samples.  They noted that that when they combusted a pure element it produced a characteristic set of lines, a spectral fingerprint, that could be used to identify it.

In October of 1860, Kirchhoff and Bunsen announced they had used their spectroscope to discover a new chemical element, which they named cesium, for the blue color of its principal line.  Chemists quickly began to use Bunsen’s spectroscope to find new elements.  A few months later Kirchhoff and Bunsen found two bright ruby red lines in an extract of a silicate mineral lepidolite, the spectral traces of another new element, rubidium.

Thallium’s ghostly green emanations were first observed by William Crookes, indium, ironically named for its violet lines by its color blind discoverer Ferdinand Reich.  Paul-Émile Lecoq de Boisbaudran spectroscopically painstakingly identified element 66 in a sample extracted from his marble hearth, and instead of naming it for the colors of the lines, called it dysprosium, from the Greek for “hard to get” — because it was.

Hunting for new elements spectroscopically meant you didn’t actually need to have any of it in your lab or even on your planet, as long as you could observe the light from a burning sample.  In 1868 several chemists and astronomers independently observed a faint line in the spectrum of the sun, and assigned it to a new element, helium, which as far as they knew did not exist on earth.  It would take nearly 30 years for two Swedish chemists to confirm that it was present on earth — by matching the spectrum with that of a gas found in a uranium ore.  (All the helium found on earth comes from radioactive decay.)

These ghostly lines produced by elements helped fuel yet another critical discovery that would have far reaching consequences for chemists’ understanding of the periodic table:  quantum mechanics.  Niels Bohr’s quantum mechanical model of the atom opened the door to explaining the line spectra of chemical elements. Though more accurate and sophisticated quantum mechanical models of the atom now exist, Bohr’s model showed the relationship between the lines and an atom’s electron by insisting that the electrons’ energies were quantized, that is, they could only have certain energies.

So why do atoms have ghosts?  When an atom is heated to high temperatures, as in a flame or a star, the energy it absorbs excites its electrons.  You can think of the electrons in an atom as being on an energy ladder. (this isn’t quite correct as far as the quantum mechanics goes, but it is a reasonable approximation and easier to visualize.)  They can only have energies that match the rungs of the ladder, and each type of atom has a unique arrangement of the rungs.

When an atom absorbs energy, its electrons move to higher rungs.  Excited electrons are unstable. They quickly return to their original arrangement, giving off some their excess energy in the form of light as they fall back to their original rung.  The color (the wavelength) of the light emitted depends on the difference in energy between the rungs.  The colors of light emitted are the ghosts of the energy rungs.  Since each element has a unique pattern of rungs, it will have a unique spectrum of emitted light and so revealing their presence to the sharp eyes of spectroscopists.

The spectra that Secchi so carefully observed (and hand drew!) were not just a way to identify a particular star, but clues to its chemical composition and even more critically to its evolution. Chemists and astrophysicists still use the light emitted and absorbed by atoms and molecules to identify their presence.  We hunt for the structure of the universe in its ghosts.

If you want a way to see the ghosts of atoms for yourself, try this inexpensive DIY folding spectroscope you can attach to your phone. Use it to check out the light from a neon sign or from a street light!

For a wonderful description of the elements, including stories of how they were first discovered, read John Emsley’s Nature’s Building Blocks.

Want to read more about Angelo Secchi, SJ? Try Adam Hincks SJ's piece in American Magazine or my colleague at the Specola Bob Macke SJ's piece about Secchi's more terrestrial scientific pursuits.

This post is a version of an essay written for a collection commissioned for the UN’s International Year of Light in 2015.  

Tuesday, August 07, 2018

Walking in the heat

Public gardens in Albano.
The sensible thing to do when it is 96o F out is to take a nap. Truly.  Instead I have been walking. Yesterday I walked across the bridge at the far end of town which spans the valley separating Albano from Arricia. Today I walked the gardens in Albano, just below the Specola.

The views have been spectacular, towns and small orchards spread out below like toys. But part of the joy of the walking is what I can see at this pace. The discovery of the grotto underneath the plaza where I cross the street most days to pick up a loaf of bread.  The doorknockers and door stops, lion's heads and horses' hooves. And my favorite, which reminds me of Thing in the Addams Family (the hand in the box on the table).

It's also interesting to experience these towns as they were when foot travel was the only choice. I can walk from the center of historic Albano to Castel Gandolfo in under 30 minutes. The same can be said for the walk to Ariccia. Many of my walks parallel the Appian Way, or follow it for short periods. These are well worn paths, Ariccia has been settled for almost 3000 years, Albano, in this location at least, for 2000 years.

Though the walk from Albano to Arricia is much faster now that the bridge spans the valley, before the bridge was built in the mid 19th century by Pope Pius IX...well, not with his own had to walk down and up a very steep slope The country here is steep, I think twice before walking down a street, knowing I'll have to walk up it to get back.

The bridge is not the original bridge, but was destroyed by retreating German Army at the end of World War II, was rebuilt and then collapsed abruptly in 1967 (which created such wonderful ruins that they inspired Fellini to film there). I think I was glad not to know about the collapse as I walk across the once-again-rebuilt span.

Monday, August 06, 2018

The epitome of epithymy

Dictionary in the library at Jesuit Center in Wernersville.
The son known herein as Crash recently pointed out to me a feature of the online version of my beloved1 Oxford English Dictionary which I hadn't noticed before.  Words are assigned to one of eight frequency bands.

Bands 7 and 8 are common words in speech and writing, appearing with a frequency of one word in a thousand or more.  Band 4  comprises words that appear less commonly, roughly one word in a million, but "most words remain recognizable to English-speakers, and are likely be used unproblematically in fiction or journalism." Example - bipartisan, which may appear more often these days than one might be led to assume from this.

I'm working on an essay for Nature Chemistry on chemists' tendency to use epithymetic language when talking about atoms or molecules.  Epithymetic is the perfect word to use in this context. It is also in Band 2, which the OED describes thus (emphasis mine)
Band 2 contains words which occur fewer than 0.01 times per million words in typical modern English usage. These are almost exclusively terms which are not part of normal discourse and would be unknown to most people. Many are technical terms from specialized discourses. Examples taken from the most frequently attested part of the band include decanate, ennead, and scintillometer (nouns), geogenic, abactinal (adjectives), absterge and satinize (verbs). In the lower frequencies of the band, words are uniformly strange or exotic, e.g. smother-kiln, haver-cake, and sprunt (nouns), hidlings, unwhigged, supersubtilized, and gummose (adjectives), pantle, cloit, and stoothe (verbs), lawnly, acoast, and acicularly (adverbs), whethersoever (conjunction).
Yeah, no. I won't be using epithymetic anywhere in that piece.

On the plus side, I'm adding some uniformly strange and exotic words to my vocabulary this week. Urusula La Guin's essay on the use of the word f*ck in discourse added swounds and gorblimey. Swounds is a euphemistic shortening of God's wounds; gorblimey, is another shortened oath, God blind me. Swounds is Band 1 - the zebras of the word world.   The frequency band information gave me sprunt, for spruce and smart. My office at home is pretty sprunt these days, after my summer's efforts to clean things up.

I would like to state clearly that I did not marry Math Man merely to get the two volume OED with the magnifying glass in the little drawer, though it made a very nice dowry (Band 5), I must say.

Epithymetic means "connected to desire, about appetites" - and this piece is about the language of desire, about electrophilicity and nucleophilicity and electron affinities.  See, it's perfect.