Thursday, September 14, 2017

Aliens have landed on my roof

Classes have begun at the college, a season about which I have selective amnesia.  No matter how many times I have done this (33 times, I'm counting), no matter how prepared I am with handouts and room arrangements and...it is always nervewrackingly chaotic and utterly exhausting.  It's fun like riding a really big wave is, equal parts exhilaration and terror, and you can feel pretty bedraggled by the time you wash up on the beach.

And of course, while you are riding this wave of new school year energy, you can't do anything else. All this to say, it felt delightful today to have some quiet time to do some research and a bit of reading.

I had Jon Larsen's  In Search of Stardust1 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.2 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 meteorite 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 each year, most of them landing in the water.  But what takes my breath away are the hundreds of trillions of micrometeorites that come to rest on earth each year, adding as much as 100,000 metric tons to the earth's mass.  Invisible, unremarked.  Perhaps as many as one a day hits the roof of my house, there are surely some of these ancient bits of dust in the water I drink, still others stuck to my hands after weeding the garden.

Larsen, a Norwegian jazz musician, discovered that you could find and identify these micrometeorites by looking at the dust on urban roofs, previously it had been thought you couldn't find them in the midst of the general detritus of a city. But a careful eye is rewarded, as these cosmic intruders have a characteristic morphology. Their shape and appearance means you can sort them out under a microscope, much like Pasteur manually sorted the crystals of tartaric acid, and they are astonishingly beautiful.
From J. Larsen, In Search of Stardust , p. 51.

Larsen offers a brief and readable glimpse into the science of micrometeorites, but I enjoyed simply browsing the images, reading them as I might clouds.  There is a golden glass meteorite with deep blue inclusions (p 51) that looks like some alien aquatic creature's shell, while the burnished cryptocrystalline specimen on page 45 looks like a bronzed wasp's nest — until one remembers it is less than a millimeter long. One scanning electron microscopic image of an ablation spherule from the meteor that exploded over Chelyabinsk, Russia in 2013 looks like a tiny alien skull.

As much as I learned about the dust from outer space, Larsen's register of the terrestrial imposters gave me an entirely different view of road dust, which contains polished spheres of glass from the reflective markings on the roads and tiny crystals, microgemstones.

In one of the most beautiful passages in Isaiah (Is 54:11-12) we are told, "I lay your pavements in carnelians..." Who knew it was literally true.  The world is a beautiful place, if only we know where and how to look.

(A version of this post appeared at the Vatican Observatory Foundation's Catholic Astronomer blog.)


1. J. Larsen, In Search of Stardust   If you get it at Amazon through this link, the Vatican Observatory Foundation will get a donation. There was an article in the NY Times last spring about the project as well.

2. Guy J. Consolmagno, Martha W. Schaefer, Bradley E. Schaefer, Daniel T. Britt, Robert J. Macke, Michael C. Nolan, Ellen S. Howell, "The measurement of meteorite heat capacity at low temperatures using liquid nitrogen vaporization" Planetary and Space Science87 (2013) 146-156

Wednesday, September 06, 2017

Renewing vows: 9131 days

It's the nine thousand one hundred and thirty first day since Math Man and I walked through the doors of the parish church, processed down the aisle and vowed to stand by each other and cherish each other in weal and in woe.

It's our 25th anniversary, if you don't want to do the math (yes, Math Man included the leap years!).  It's not a prime number, but composite, with a prime factorization of 23 x 397.

Our sons had a life sized photo cutout of us made and restaged the wedding — right where it happened in our parish church. It is an entirely different take on renewing your vows.  They photographed the 'event' and gave us the photos (and the cutout) for an anniversary present.

It seems unthinkable that we've been married more than 13 million minutes, millions seem so large and the time so short.  Other significant dates to come?  On January 22, 2020 we will have been married 10,000 days and on Monday, May 13, 2024 for a billion seconds.  Billions and billions. And yes, these days are on my calendar!

Tuesday, September 05, 2017

Labor, crosses, prophets and floods

I've lost count of laundry loads and dishwasher runs and dinners cooked, the house has been bouncing since I got back from Rome in early August. The boys have come and gone again, back to school and work, one to the east, the other west.  The Egg's friends have come to visit, sleeping on sofas.

The long and short of serving.
My sister-in-law, No-no came to drop my niece, She of the Book, off at college.  From Houston.  They arrived here the day Harvey hit, awoke Sunday morning to texts from my brother Geek Guru that the waters of the nearby bayou had risen fast and he and my nephew were shocked to find they were now trapped in the house.  They spent a damp, dark day surrounded by flood waters, checked on by police on a Zodiac, watching neighbors get pulled out by boat and helicopter.

They are, I am relieved to say, now safe. When the waters went down, they evacuated to my other Houston brother's house. The house is OK, it was raised up past the 100 year flood level.  The garage and the cars in it?  Toast.

Labor, crosses, prophets and floods. And yet still, ordinary time.