Grand Finale – Painting inspired by the Cassini Mission to Saturn
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Also in Exploring the Solar System Exploring the Solar System: The Mass of the Sun Marvellous Mars Drawing Workshop at Dunsink Observatory Dublin Astronomical Sketching – Education in action Stars Wonderful Stars at Wexford Town Library Ireland Get ready the Perseids are coming Space the final Frontier – World Space Week 2016 On the richness of the lunar surface Dark Sky Magic at Ballycroy National Park Mayo Ireland Grand Finale – Painting inspired by the Cassini Mission to Saturn Cosmic Lobster Pot A Slice of Solar Drawing in h-alpha View the entire series … Continue reading

Across the Universe: Confronting Fear and Terror
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This column first appeared in The Tablet in October 2011 Following the Phobos session at the joint European-American Planetary Science Conference, held[in 2011] in Nantes, France, my colleague Dan Britt commented, “You know the origin of Phobos and Deimos…” These moons of Mars, named for the Roman gods of fear and terror, are 10-km sized potato-shaped piles of rubble. Pockmarked by craters, they look just like the kind of dark bodies you see in the neighbouring asteroid belt. “They’re captured asteroids, right?” I replied. “That’s what we think in America,” Dan replied. “But in Europe, apparently, everyone is convinced that they are actually made from material splashed off the crust of Mars by a giant impact.” For years, Dan had been trying to convince NASA to spend a spacecraft to Phobos. He argued that if you could collect enough rocks from its surface and bring them back to Earth, you would get not only asteroidal material but also an occasional rock that might … Continue reading

Across the Universe: Featureless Features
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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: A Damp Kaboom
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This column first appeared in The Tablet in October 2009 “Where’s the kaboom?” asked my friend, imitating the whiny voice of the cartoon character Marvin the Martian. “There was supposed to be a Moon-shattering kaboom!” We were watching live television coverage of NASA’s LCROSS lunar orbiter impacting into a dark crater on the Moon. The idea was that water ice might be hidden in the shadows of craters like this one, set in a region of the Moon’s south pole where sunshine never reaches. Water vapor from all the comets that have hit the Moon over the last four billion years might be trapped and frozen there. By slamming a rocket into those shadows, a giant plume of rock and ice would be lifted out of the shadows and into the view of the nearby spacecraft, and telescopes on Earth. Or so proclaimed the hyperactive NASA press office. In fact, at the impact, only a faint infrared blip was visible in the spacecraft images. … Continue reading

Across the Universe: Gift of Tongues
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This column first ran in The Tablet in May, 2012 “Men of Galilee, why are you standing there looking at the sky?” We heard that reading a week ago, celebrating the feast of the Ascension. At least, I think that’s what I heard; [in 2012], it was in Japanese, in the small cathedral in Niigata, during an international meeting on asteroids, comets, and meteors. Why do we astronomers stand about, looking at the sky? We heard a number of reasons. One scientist described Nasa’s ambitions to send astronauts to asteroids passing near the Earth. Their expressed reasons involve science (where do asteroids, and we, come from?); resources (commercial efforts to exploit asteroids); and planetary safety (how do we nudge an asteroid out of a collision path with Earth?). The unspoken motivation is political: astronauts at an asteroid is the kind of project that is both exciting and achievable, a reason for voters to support NASA’s budget. We know right now … Continue reading

Across the Universe: Dramatic Science
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This column first ran in The Tablet in April 2008. From a glass-enclosed visitor’s gallery at the Jet Propulsion Laboratory (JPL) in Pasadena, California, I watched three technicians, encased in white suits, slowly affix bits of equipment to a large aluminum frame, the platform of an SUV-sized rover to Mars. Two sets of steering rockets were already attached; two large metal spheres painted black and gold were seated nearby. “Those are the fuel tanks, right?” I asked my friend Steve, an engineer on the project who guided my tour. “Like the ones that blew up the Mars Orbiter in the 1980s?” Every piece has a necessary function, and every piece has a history of what can happen if it goes wrong. Even with a recent string of triumphs, Mars probe failures still outnumber the successes. Each piece is added in a carefully scripted order, with a quality-control specialist looking on: the torque wrench must not overtighten a nut, the accelerometer must not … Continue reading

Across the Universe: Europa
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This column first ran in The Tablet in February, 2009 Under the dim light of a distant sun, a cold white ball smaller than our Moon orbits a huge gas planet, garishly striped with colored clouds. Galileo first saw this jovian moon – to be named “Europa” by his rival, Simon Marius – on January 7, 1610. In 1805, Laplace had worked out Europa’s mass (using an elaborate theory of the moons’ orbits), and other 19th century astronomers timed the way the Jupiter moons shadowed each other to estimate their sizes. By the end of that century clever instruments allowed Pickering to estimate its brightness. All the information was there. From these data, any schoolchild could have calculated that Europa was less dense than rock, more dense than ice, and brilliantly white. But no one actually put all that information together until 1908, when Pickering finally noted the low density and bright surface… and speculated that this Jupiter moon was a … Continue reading

Across the Universe: Relish the Red Planet
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An edited version of this article first appeared in The Tablet in January, 2004. It was the first column I wrote for them. I spent Christmas morning [2004] with my brother Edwin, amid the snow and frigid winds whirling across Lake Superior and around the tiny city of Marquette, Michigan. Between Christmas Mass and Christmas dinner, I kept an eye all day on my computer, checking the BBC web site every few hours, hoping to hear news of the British Mars lander, the Beagle II. Alas, though the Beagle had landed, we never heard it bark. I felt for my friends on the science team, Colin and Ian and the others, watching with ever fainter hope as the dream they’d pursued through the years of planning and fund-raising, constructing and testing, launching into space and guiding to the surface of the planet, finally at the last minute failed. Landing a probe successfully on Mars is a very difficult proposition; the … Continue reading

Across the Universe: Souvenirs from Space
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This column first appeared in The Tablet in October, 2004 Typhoon 23 and I arrived in Japan on the same day. My mission (I can’t speak for the typhoon) was to attend an international workshop on sample returns from asteroids. Our hosts were the  scientists and engineers of  the Japan Aerospace Exploration Agency who are eagerly awaiting the arrival next summer of their spacecraft, Hayabusa, at asteroid Itokawa. (The remarkable challenges and eventually successes of Hayabusa can are described nicely at its Wikipedia site.) Astronomers usually have to be content with observing their objects from afar. But nothing beats actually going to a place to see what it’s really like. Itokawa is a potato-shaped lump of rock less than half a kilometer in diameter that apparently drifted into our neighborhood from the asteroid belt; though it looks like a typical asteroid, its orbit is not out beyond Mars but rather much closer to home, crossing the Earth’s orbit nearly once … Continue reading

Across the Universe: Deep Impact
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This article from The Tablet was first published in June, 2005, a mere ten years ago, just before the “Deep Impact” probe hit. The flyby of the comet then, parallels the flyby of Pluto by New Horizons next month. It’s interesting to see what we were hoping to learn… how little we knew; how little we know. The folks who work out the celestial mechanics of space probes are a clever bunch, with a techie’s sense of humor. A few years ago, the NEAR spacecraft arrived at asteroid Eros on Valentine’s Day. The ill-fated Beagle 2 probe was designed to land on Mars on Christmas morning (not the only present that Christmas to arrive broken, I suspect). And this year [2005], on the Fourth of July, an American probe called “Deep Impact” hopes to make a splash as dramatic as any fireworks display by plunging at 37,100 kilometers per hour – London to New York in nine minutes – into the nucleus of the comet Temple … Continue reading

Across the Universe: By Paper, to the Stars
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This column was first published in The Tablet in June, 2004… read the end to find out what happened! The people who design airplanes say that a plane can’t fly until its weight is matched by the weight of its paperwork. The same must be true for launching spacecraft to another planet. Last month [May 2004] I took part on a NASA panel in Washington DC, reviewing five competing plans to build a planetary probe; in the run-up to the panel I was shipped 30 pounds of paper to read. NASA’s “New Frontiers” program is a development of another project driven by piles of paperwork: the Solar System Decadal Survey commissioned by NASA and executed by the National Academy of Sciences in 2002. After hearing from hundreds of planetary scientists at meetings around the world (and reading white papers solicited and gathered by various international  societies) a committee of graybeards outlined where NASA should be spending its money over the next … Continue reading

In Praise of Flyby Missions, Part One
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I was chatting with a friend in an online forum when the subject of Pluto came up. He is quite knowledgeable about spaceflight, but has not followed the New Horizons mission closely. My friend expressed disappointment at learning that New Horizons was a flyby, not an orbiter, and would only spend a few hours in close proximity to Pluto and its moons. I suppose that he may have in mind all the spacecraft which, in the last decade or so, have been orbiting other planets. There’s Cassini circling Saturn, Messenger circling Mercury, and whole fleets of Venus and Mars orbiters, to say nothing of the multiple rovers on the surface of Mars. We’ve also seen probes orbiting several asteroids and the Moon. Perhaps he’s accustomed to the luxury of images and other scientific results streaming constantly Earthward. At irregular intervals, scientists hold a press conference and show us another planetary wonder or two. Pluto’s different. It’s never been visited, and … Continue reading