Next week I am off to St. Petersburg (Russia, not Florida) to give an invited lecture at the 4th International Conference on the Periodic Table — a celebration of the 150th anniversary of Dmitri Mendeleev’s proposal that the chemical elements could be laid out in a table where elements in each row (now columns) shared many properties. This periodicity of properties led this method of organization to be called a “periodic table.” Pope Paul VI in one of the Vatican Observatory’s domes reading a message to the Apollo 11 astronauts. The lecture I’ve been asked to give is based on an essay I wrote for Nature Chemistry earlier this year, “Isotopic Enrichment” (Isotopes are variants on elements. For example, carbon-14 dating tracks the radioactive decay of a heavier than normal variant of a carbon atom. Most carbon is carbon-12, where the number indicates the mass of a single atom,) The title of this blog post comes from an article ten years ago in … Continue reading →
About Dr. Michelle Francl
Michelle M. Francl, Ph.D. is a Professor of Chemistry at Bryn Mawr College, where she has been on the faculty since 1986, and an Adjunct Scholar of the Vatican Observatory. She is a quantum chemist who has developed theoretical methods for computational chemistry and who is interested in the structures of molecules that behave in ways that chemists might not predict they do. She is interested in the philosophy and history of chemistry, and her essays on science, culture and policy appear regularly in Nature Chemistry. She was elected a Fellow of the American Chemical Society in 2009.
Michelle is also a theologian whose reflections on trying to live a contemplative life in the midst of the everyday chaos that comes with being a teacher, wife and mother can be found in a number of print and online venues. Her most recent book, a Lenten devotional, is Not By Bread Alone, and in a new audioseries"Seeking the Face of God: The Lives and Discoveries of Catholic Scientists," she and Br. Guy Consolmagno, SJ muse on the intersection between Catholic faith and the practice of science. She gives the occasional retreat, and blogs on life, laundry, prayer and God at Quantum Theology.
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 … Continue reading →
[A version of this appeared at CatholicPhilly.com in July 2010.] On Friday, I walked onto the driveway to call the cat in for the night, peering under her favorite bushes, warmed by the brick wall of the house. I happened to look up. There, on a velvety deep cobalt sky, perfectly framed between two towering trees across the street, was a brilliant Venus and a slim crescent of the moon. The sight took my breath away, so much so that after a moment, I went back inside and pulled my husband out of bed to come see. As I sat on the driveway, watching the moon inexorably slip away, I remembered an evening sitting on a bench outside the Jesuit retreat house on Eastern Point in Massachusetts. The bench faced east, not west, so instead of watching the fiery exuberant swirls of red and gold over Gloucester bay, my view was one of an impending darkness extending further than I … Continue reading →
When I ran across the paper that gave the title to this post, it seemed as if it would make a wonderful title to a poem, perhaps one by Marilyn Nelson or Billy Collins, about what is hidden in plain sight – the airglow, and some of the early women in science. The moon and stars are not the only lights in the night sky, the very envelope of air that surrounds us glows, day or night. One of the sources of the earth’s airglow is a 3 mile deep layer of sodium atoms about 50 miles above the earth’s surface. There are roughly 8000 sodium atoms in a milliliter of air up there. In fact, there’s not much air at all, the pressure is about a millionth of what it is as sea level. Even so, only 4 in a billion of the atoms in that layer of the atmosphere are sodium. When these sodium atoms get energetically excited, … Continue reading →
In the beginning was the Word, and the Word was with God, and the Word was God. All things came to be through him, and without him nothing came to be. What came to be through him was life, and this life was the light of the human race; the light shines in the darkness, and the darkness has not overcome it. John 1:1,3-5 “And by light you mean photons, right?” asks the student in the first row. “Yes, I do.” At least in this context. There is always a bit of irony in these last classes of the semester. I’m lecturing about light — about lasers and spectroscopy, photons and selection rules — as the winter darkness grows deeper. Or maybe it’s not such an unreasonable topic for these solstice-ing days. As I packed up to return to my office, the lines from the Prologue to St. John’s Gospel ran through my head, “the light shines in the darkness and the … Continue reading →
The Total Solar Eclipse of August 21, 2017 – fly along with the shadow! from Eclipse2017.org on Vimeo. Not quite two months ago I spent a late morning and early afternoon watching the moon slide across the sun, turning midday Philadelphia into twilight and back again. I stashed the eclipse filters for the occasional look at the sun, and dove into the semester. But each time I head out for a late evening walk and see the moon hanging over the neighborhood school’s field, I think about it coming between the earth and the sun. I tend to think of the moon and sun as large objects ponderously processing through space, from my perspective taking ten or a dozen hours to creak ’round the sky. Their movements mark out days, months and years, not so much minutes and seconds. So I was struck on the animations of the August 2017 eclipse by how fast the moon’s shadow moved across the … Continue reading →
I have had Jon Larsen’s In Search of Stardust on my stack of books to read because last spring the upper division research methods course I taught did an experiment to measure the heat capacities of meteorites, using the method developed by the Vatican Observatory’s Guy Consolmagno, SJ and Bob Macke, SJ and colleagues. The students were curious about the astrochemistry context (where do the samples come from, how can you distinguish regular rocks from these stony aliens) and I’ve been collecting resources for this coming spring when a new batch of students will make these measurements. I tend to think of meteor strikes as spectacular and rare events, fireballs roaring through the sky that finally come crashing to earth. Still they aren’t as rare was you might think — tens of thousands of meteorites weighing as much or more than a euro coin hit the earth’s surface each year, most of them landing in the water. It gives me a visceral … Continue reading →
“Aunt Chel,” called my youngest niece as she bounded through the front door of my dad’s house, “it looks funny outside.” I got up and went to check. I agreed, something was off. The sky was dimmer than it should be and an odd color, not the desert blue I expected late on a Sunday afternoon, but tinged green. Thunderstorm incoming? No, not a cloud in the sky. And I’m in the desert. Right. Fire? This is more of a worry, there is only one road out from my dad’s small farm. We don’t smell smoke, but still, I’m uneasy. And then there are the trees….something is just not right. We go back inside to check if there is anything on the Cal Fire site about nearby fires. My dad and sister-in-law have worried looks on their faces as I describe the sky, will we need to evacuate? As I’m opening up my laptop , my stepmother mentions in passing … Continue reading →