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Continue reading →Tag Archives: meteorites
ⓜ Speaking of speaking online: Diary of 19 August, 2020
It seems odd to write an online diary about how much time I have been spending online, but I am sure that my experience is hardly any different from yours. Except… for the past twenty-plus years my life had been constant travel, reaching the top rank of my airline’s frequent flier status regularly, as I would go not only to Rome and back several times a year but also around North America and Europe giving talks and attending conferences. But now I haven’t left home since George Coyne’s funeral last February. (Speaking of which, be sure to check out the George Coyne memorial page, as several new memories have been posted in the past month or so.) It’s the longest I have been in one place since at least 2003, which is how far back I kept track of my calendar on my computer. I suspect it’s the longest I’ve been in one place since I joined the Vatican Observatory … Continue reading →
ⓜ Meteorites, Ice, and Antarctica: A Personal Account of William A. Cassidy
And then I wrote… Last month in this space I ran a number of book reviews. I was planning to go back to more of them later in the year, but with the recent death (March 22) of Bill Cassidy, the man who founded the Antarctic Search for Meteorites program, I thought it would be timely to run here a copy of the review I wrote in 2003 of his classic book on Antarctic Meteorite hunting. Oddly enough, this article was not listed in my own personal bibliography and so it took a bit of looking to figure if and where it actually was published. From the internal evidence I figured out that it had been written for the late, lamented Meteorite! Magazine but since that went out of business many years back, it doesn’t have a convenient web site to check. Fortunately, among the past editors were our own Larry and Nancy Lebofsky. They looked through their back issues and discovered that it had … Continue reading →
In the Sky This Week – February 25, 2020
The constellation Orion is moving slowly towards the west each evening; the star Betelgeuse has been dimming since last year, and is no longer in the top 25 brightest stars – which several of my astronomer friends have commented is “just weird!” As I was writing this post, I saw on SpaceWeather.com that apparently the dimming of Betelgeuse has stopped. Predawn observers have three planets to choose from above the southeastern horizon: Saturn, Jupiter and Mars. The crescent Moon joins Venus above the western horizon at dusk from February 25th – 28th. The Moon appears near the star Aldebaran at 10:00 PM on March 1st – 2nd. The Moon is a waxing crescent, visible toward the southwest in early evening. The first quarter Moon occurs on March 2nd, it will be visible high in the southern sky in early evening. Moon News: Historic NASA Mathematician Katherine Johnson Dies at Age 101 This morning, a NASA hero passed away at the … Continue reading →
Across the Universe: Featureless Features
At the end of September 2016, Rosetta finally ended its mission by crashing into its comet. This column, about an earlier aspect of the Rosetta mission, first appeared in The Tablet in October 2010; we first ran it here in 2016. Back in July [2010], ESA’s Rosetta spacecraft, en route to a comet rendezvous in 2014, flew past asteroid Lutetia, a 100 km pile of rock orbiting between Mars and Jupiter. The result of that encounter was a hot topic of both the European Planetary Science Conference in Rome in September and a meeting of American planetary astronomers in Pasadena in October [2010]. Studying asteroids has always been challenging. Even in the largest telescopes they’re mere dots of light, too small to show any shapes, much less surface details. We can only infer their nature from the most subtle of hints: how their brightness varies as they spin, how much infrared light they radiate, their visible and infrared colours. Minerals that contain … Continue reading →
Across the Universe: Words that Change Reality
My columns for The Tablet often act as a diary of sorts, recording important events in science or in my own life. Such is this column, which first ran in September, 2006. We first ran it here in 2015. Ten years ago last month [as of 2006 – now 23 years ago!], Dave McKay and his colleagues at NASA’s Johnson Space Center in Houston announced that a meteorite, believed to have come from Mars, showed evidence of microbial life. Their interpretations are still widely disputed by the meteoritics community. But, oddly, their announcement resulted in one major change of attitudes. Before, there were still skeptics who were not sure that those rocks came from Mars; now, as the skeptics argue about the putative biogenic grains found in it, no one doubts the Martian origin anymore! Some of us can only be skeptical of one thing at a time, I guess. Still, what you call the meteorite doesn’t really change its … Continue reading →
Across the Universe: Relics of Space
This column from The Tablet first ran there in September 2018… I have altered it slightly to bring it up to date. The famous American cynic H. L. Mencken once asserted that every question had an answer that was “neat, plausible, and wrong.” Science is no different. Our meteorite collections have reddish “ordinary” meteorites and black “carbonaceous” ones; meanwhile, in space we see some asteroids with reddish surfaces, while others are pitch black. The connection between the meteorites and the asteroids is thus neat and plausible. But is it right? The holy grail in asteroids is finding the ones with water and carbon. If we are going to be a space-faring species, we’ll need those chemicals to feed us and power our spacecraft. The cost to bring them up to space with us from Earth makes these materials far more valuable than platinum or gold. We know that some carbonaceous meteorites have carbon and water; and they are distinctively black. … Continue reading →
Religious Scientists: Fr. Domenico Troili S.J. (1722-1792), Meteoriticist
Today, I get to indulge in a couple topics that are important to me: meteorites and Jesuits. There are a few modern points of intersection of the two topics, including Br. Guy Consolmagno, Fr. Cyril Opeil, and myself. For this entry, however, we go back in time a couple of centuries to Fr. Domenico Troili, who lent his name to one of the most common minerals found in meteorites. Troili was a former pupil of the Fr. Roger Boscovich S.J. at the Roman College. (Boscovich is another religious scientist who will be discussed in a future blog post for his contribution to atomic theory.) He later became the curator of the Este family library in Modena, Italy. He witnessed the fall of a meteorite over Albareto, Italy in 1766. He took pains to document eyewitness accounts and collect specimens of the Albareto meteorite. This makes him the first person to formally document a meteorite fall, in Ragionamento della Caduta di un … Continue reading →
Across the Universe: Help My Unbelief
This column was published in The Tablet in August, 2007, and first ran here in 2015 We believe in things we don’t see — like electrons, or black holes — because they let us make sense of things we do see. But sometimes we don’t believe, even when we see. The question of what we believe, and why we believe in it, struck me particularly at the [2007] annual meeting of the Meteoritical Society. A French mathematician has analyzed the dates meteorites have been seen to fall over the past 200 years and found clear trends, at the 90% confidence level: more meteorites than usual tend to fall every 3 years, every 10 years, and every 17 years. His analysis is standard, straightforward stuff; but I don’t believe it. Nor did anyone else in the audience. Two hundred years just doesn’t seem long enough to show such periodicities. And we’ve been burned before with theories that had only a 10% … Continue reading →
Across the Universe: Key to the Sea and Sky
This column first ran in The Tablet in July 2007; we first ran it here in 2015. In Alicante, on Spain’s Mediterranean coast, a group of us planetary astronomers held a workshop [in 2007] on how asteroids respond to the massive collisions that can lead to their catastrophic disruption. Just north of us, in Valencia, sailors from Switzerland and New Zealand were vying for the America’s Cup. The connection between elegant million dollar yachts and exploding asteroids. is the equations of fluid dynamics. I’ve loved sailing since my childhood. I spent my summers capsizing sailboards on Lake Huron and my winters reading too much Arthur Ransome. As a student in the early 1970s I competed on MIT’s sailing team (the Charles River was indeed “dirty water” especially back then), and attended lectures in their ocean engineering department on the challenges of designing the best shape for a hull that could slip through the water with a minimum of friction while … Continue reading →
Across the Universe: One Fix Leads to Another
First published in The Tablet in February, 2007; we first ran it here in 2016. I’ve moved it to March, this year, to fit the Lenten season. With my colleague Dan Britt from the University of Central Florida, for several years I’ve been measuring the densities and porosities of meteorites. The densities of different meteorite classes can be compared with their parent asteroids, to see how loosely packed they are; and the porosity of these rocks is an indication of how thoroughly their fabric has been cracked by the shock of the impacts that shattered those parent bodies. We started with the collection I curate at the Vatican; but there are many meteorite types that are underrepresented there. When I came to New York [in 2007] for a year’s sabbatical at Fordham University, I had hoped to extend our data by looking at the nearby American Museum of Natural History’s extensive collection. But things got off to a slow start. … Continue reading →
Gems, Minerals,… and Meteorites!
Every year, from the end of January until about mid-February, Tucson hosts the annual Tucson Gem & Mineral Show. Many cities host gem shows, most often occupying a large ballroom, convention space, or meeting hall. At such shows, collectors and dealers display and sell colorful rocks and minerals, fossils, jewelry, and geological specimens of all types. What makes the Tucson show unique is its size. As Ed Sullivan would say, it is a “reallybig shew.” Tucson hosts not just one show, but just under fifty of them, spread around various locations throughout the city. Practically every motel and vacant lot around town is transformed into a marketplace, each filled with vendors from all over the world peddling their wares. I have come to Tucson every year for the gem show ever since I took on the job of meteorite curator at the Vatican Observatory, for one simple reason–such an event also draws in those who buy and sell meteorites. This … Continue reading →