Across the Universe: Touched by Heaven
avatar

This column first ran in The Tablet in January 2014 On February, 15, 2013 [one year before this column first ran], a twenty-meter chunk of space rock hit the Earth over Chelyabinsk, Siberia. Shining brighter than the sun, its fall was recorded by video cameras as far as 700 km away. Thousands of people in Chelyabinsk ran to their windows to see what that bright light was; a few moments later, the impact’s sonic boom arrived and shattered those windows. More than 1500 people were hurt by flying glass and debris. Seventy kilometers west of Chelyabinsk, an eight meter wide hole was found in the ice of Lake Chebarkul; last summer, a half-ton meteorite was recovered from the lake bottom. It’s not every day that a rock with half a megaton of energy hits the Earth above a major city (a million people live in Chelyabinsk). But near earth asteroids are hardly rare. The Minor Planet Center in Cambridge, Massachusetts, keeps … Continue reading

Across the Universe: The New Paganism
avatar

The following column was published in The Tablet in November 2009 You will know the end-times by their signs, we’re told in the Gospel readings at this time of year. Given the nature of those signs, mostly dramatic events in the sky, you can imagine the kinds of questions that are typically addressed to those of us who study meteorite falls. The apocalyptic visions in the Gospels bear a certain resemblance to our understanding of the destruction that an asteroid impact would produce. Is it mere coincidence? Do I have any advice for the fearful? Yes: read the Gospel passages in their context as lessons on how to live, not how we’ll die. Meanwhile, quit smoking and wear your seat belt. That said, what does science tell us about the end of the world? We know that our solar system has a finite lifetime. Stars like our Sun can only shine for about ten billion years before they run out of … Continue reading

Across the Universe: Featureless Features
avatar

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   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 iron oxide or water reveal themselves by … Continue reading

Across the Universe: Stellar Round Up
avatar

This column first appeared in The Tablet in October 2008 Black Mesa, Oklahoma sounds like the setting for a Hollywood Western. It looks like one, too. Every year at the Okie-Tex Star Party, three hundred amateur astronomers camp out for a week with their telescopes there, in hopes of dark dry skies. Some of their “amateur” instruments are larger in aperture than the telescopes of the Vatican Observatory in Castel Gandolfo. The miracle of computerized fabrication and the modern Dobsonian mount (a way of holding a telescope in place that replaces complex hardware with simple Teflon pads) has brought the cost of quality optics to the point where the price of a large telescope can be less than that of a small automobile. My GPS unit directed me as far as Boise City, two hours north of Amarillo, Texas; after that, I was following roads too small for most maps. I was there to give a series of talks during … Continue reading

Across the Universe: Taking the Heat
avatar

This column from The Tablet first ran in September 2011 Science is a marriage of theory and experiment. Sometimes the marriage is literal. The colleagues I visited this month [2011] at Louisiana State University, Brad and Martha Schaefer, have been married 30 years; she’s a whiz in the lab, he’s a math guru. The three of us have been looking for a quick and non-destructive way to measure the heat absorbed in a meteorite when it is raised from the cold temperatures of space to the temperature where water melts. Meteoritic material is typical of the rocky stuff mixed with ice in the moons of Jupiter and Saturn; if those moons melt, the molten regions could be oceans of life beneath their icy crusts. Indeed, Jupiter’s moons deflect its magnetic field in just the way you’d expect from deep internal oceans; and, more dramatically, we actually see geysers spurting out the surface of the Saturn moon, Enceladus. If you want … Continue reading

Get ready the Perseids are coming
avatar

About 30 years ago we had a holiday in a remote location in the West of Ireland. The house was high on a grassy ridge on Bolus Head looking over St Finian’s Bay in Co Kerry. From this vantage point the 350 million year old Skellig Rocks rose like stegosaurus plates from the Atlantic Ocean. They were 16 kilometres out to sea but their jagged presence dominated the view to the South. It was early August and when darkness fell the predictable blinking of a distant lighthouse was the only manmade object discernible at sea level in the blackness. One moonless evening, the sky was crystal clear, the summer triangle was dramatically intersected by our galaxy’s river of stars, so much more touchable than the suburban view. I lay on the sun dried grass looking for Perseids, one, two, three, four, five, six, plus several in the corner of my eye within a few minutes. Time to take action, I … Continue reading

Across the Universe: Grain of truth
avatar

This column first ran in The Tablet in June, 2010. Travel, a favorite summer pastime, carries with it certain social perils. After I came back from my Peace Corps service, it was astonishing how often I would find myself uttering “when I was in Africa…” as every conversation would seem to trigger some memory I just had to share. Ten years later I added “when I was in Antarctica” to my repertoire. Thank God for patient friends. I recall telling a colleague about a star-gazing trip I was planning to Australia in August. He lamented that his only trip there was cloudy the entire week, so he didn’t get a chance to see any of the southern stars. “The only time I remember ever getting to see the Southern Cross was out Shuttle’s porthole…” One-upped by an astronaut! (Thanks, Tom Jones.) But even my astronaut friend has not had a voyage like the space probe Hayabusa. Launched by the Japanese Space Agency in … Continue reading

Across the Universe: Treasure from Heaven
avatar

This column first ran in The Tablet in May, 2009 Above the Arizona sky the night of October 5, 2008, a faint moving dot of light was captured in the Skywatch telescope. Soon its orbit was calculated, showing that this newly discovered asteroid, 2008 TC3, had only 20 hours left before it was to hit the Earth. Two dozen teams of astronomers made every possible use of that time, measuring its colors and changing brightness as it spun across the sky, and further refining its orbital path. On the morning of October 7 (local time), a tumbling lump the size of a white van struck the sky over northern Sudan. Seven months later, in a quiet conference room in Prague, Peter Jenniskens told a rapt audience of bolide and meteorite specialists (I was one) the story of what happened next. Through e-mails to friends and colleagues, this Dutch-American meteor specialist had made contact with a geologist at the University of … Continue reading

Across the Universe: Touch the Sky
avatar

This column first ran in The Tablet in April, 2010 Next summer [2011], the “Dawn” spacecraft will go into orbit around Ceres and Vesta, biggest and brightest of the asteroids. (Indeed they are so much larger than the other asteroids that they may be better classified as dwarf planets.) These bodies have been well studied by telescope for more than 200 years – Ceres was discovered on New Year’s Day, 1801, by the Sicilian priest-astronomer Giuseppe Piazzi – but seeing them remotely is nothing like getting a close-up view. [In April of 2010], a team of scientists and engineers met in Rome to prepare for Dawn’s arrival, and they spent a morning visiting our observatory in Castel Gandolfo. For reasons ranging from the way they reflect infrared light to the conclusions of computer models for their chemical evolution (including work I was involved with more than thirty years ago), we believe that certain meteorites in our collections are actual samples of … Continue reading

Three Years Since Chelyabinsk
avatar

It has been three years since an asteroid exploded in the clear morning sky over a heavily populated city in the southern Ural region. 20-30 times the energy of the Hiroshima atomic bomb was released in the explosion, the invisible shock wave crashing into the ground several minutes later, shattering windows over a wide region. Hundreds of people were injured by flying glass shards, and thousands of buildings were damaged. As asteroids go, the Chelyabinsk meteoroid was small and unremarkable: measuring about 20 meters in diameter, stony in composition, and weighing-in at about 12,000 metric tonnes. It approached the Earth unseen, and entered the Earth’s atmosphere at a shallow angle, traveling at almost 60 times the speed of sound. Friction with the upper atmosphere caused plasma to build up, and the meteoroid took on the aspects of a classic fireball: arcing brightly across the sky, and leaving a smokey contrail. Suddenly, the fireball exploded, becoming intensely bright for a few … Continue reading

Across the Universe: The Still Voice in the Chaos
avatar

This column first appeared in The Tablet in January, 2010. During the Apollo 17 walk on the Moon, the astronauts collected a rock for the specific purpose of providing samples to pass out to nations around the world. About 200 Apollo 17 samples were distributed in this way. But Robert Pearlman, who runs the space-news website collectspace.com, wrote in 2010 that NASA can now account for only 61 of them. (The one sent to the Vatican resides in our display case at the Vatican Observatory.) I’m not surprised; keeping track of samples is harder than it looks. The humor of the “Night at the Museum” movies comes from the conceit that the specimens in a museum’s display cases are alive, that they get up and move around during the night. Every collector knows that feeling. It’s surprisingly hard to keep our collections in order. One of the little breakthroughs in my own research was finding that a simple measurement of a … Continue reading

Across the Universe: Heavenly Visitors
avatar

This column first appeared in The Tablet in December, 2006. The reporter from the BBC was surprised that I wasn’t shocked: Could the seeds of life have come to Earth from outer space? He was interviewing me about a new discovery published this past month [2006] in Science. In a meteorite retrieved from a frozen lake in northern Canada, researchers found chemical compounds that could be the precursors of life in small round voids that could have served as the templates for early cells. Meteorites are my business, and the scientists cited are colleagues and friends of mine, but even so I couldn’t understand why a BBC reporter in London was trying to interview me. The data are new and intriguing, yes, but it’s hardly a new idea. For more than 150 years, meteorites have been known to contain organic chemicals. “But doesn’t the stuff of life coming to us from off the Earth contradict the Church’s teaching that only … Continue reading