Across the Universe: Feeding Curiosity
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This column first ran in The Tablet in October 2012 Finally [in 2012!], a planet has been discovered orbiting Alpha Centauri. That star, a neighbor of the Southern Cross, is actually a triplet of stars orbiting each other – as first discovered by a Jesuit missionary, Fr. Jean Richaud, some 300 years ago. And it’s is our nearest neighbor, merely four and a half light years away. Granted, the new planet orbits so close to its star (the middle member of the triplet) that its surface would be hotter than molten lava. But its existence gives hope that Alpha Centauri could also host another planet at a more temperate location, which we just haven’t seen yet. Unlike other detected planetary systems, you could actually envision a conversation with hypothetical intelligences inhabiting such a hypothetical planet; the conversation lag would be a mere nine years between exchanges. Could we go there? Half a century ago, it took Apollo about a week … Continue reading

Climate in Kurzynski Country
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I’m sorry to report that a terrific scientific and educational resource, the United States Historical Climatology Network (USHCN), is fading away.  A couple of years back the USHCN stopped updating its database—the last data available are from December 31, 2014.  Moreover, the USHCN recently reported that it was going out of business, so to speak, as of the end of this month.  Nothing lasts in the digital world. In honor of the USHCN’s fine run, and in hopes that it will stick around under some other guise, I present an analysis, based on USHCN data, of the climate in the southern Wisconsin stomping grounds of Fr. James Kurzynski, priest of the Diocese of La Crosse, Wisconsin and fellow blogger on The Catholic Astronomer.  Fr. Jim’s posts reflect an ongoing interest in ecology, and in ministering to and communicating with people who may have diverse views on the subject of climate science.  Fr. Jim and I are “team-posting” here.  I did … Continue reading

Across the Universe: Super Earths
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This column first ran in The Tablet in August 2015 Half the planets in our solar system are relatively small, rocky, and found near our sun. The other half are all significantly bigger, covered in giant atmospheres, and orbit far away from the sun. Explaining this trend in size and orbits is simple. If the planets formed from a disk of gas and dust (we’ve actually observed such disks around young stars) then planets forming farther from the sun are colder. If they’re far enough from the sun that water in the gas freezes into ice, they’ll jump up in size — a gas cloud has twice as much water as rocky material to snowball into a planet. And once a planet reaches a critical size, it captures gas from the nebula to make a thick atmosphere. So, inner rocky planets stay small; but once the icy outer planets get big enough, they jump up to even larger sizes. The … Continue reading

Across the Universe: Planetary Prejudice
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This column first ran in The Tablet in July 2015 The wonderful excitement about Pluto, visited by the New Horizons spacecraft [July 2015], has resurrected the old issue of defining a “planet”. But why? Most people approaching this question have one clear goal: they want Pluto to be a planet. Once you realize that, you can make your definition clear and simple: “A planet is one of the bodies that I was taught was a planet when I was a child.” Of course, such a definition is useless for any other purposes. The IAU, which defined Pluto and similar bodies as “dwarf planets” back in 2006, needed a definition so it could name such objects and the features on them, to know whose committee and what set of rules will apply. But there’s another aspect to this issue. Fifteen years ago I was involved in a research program studying the Trans-Neptunian Objects (TNO) that orbit alongside Pluto, comparing their shapes … Continue reading

Across the Universe: Where’s the olivine?
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This column first ran in The Tablet in July 2014 It was a beautiful theory, while it lasted. Most meteorites are well-compressed lumps of primordial dust and little beads of rock. But some are chips of lava, bits of some small asteroid that melted and sorted itself into a small iron core and a crust of frozen basaltic lava. We’ve even seen one such asteroid: the spectra colors of Vesta (the brightest, and second-biggest, of the asteroids) uniquely match these basaltic meteorites [in particular, the Howardite-Eucrite-Diogenite meteorites known familiarly as the HED meteorites]. When a mixture of various minerals gets hot, as inside a volcano, only some of those minerals melt; they make the lava that erupts to the surface, leaving behind other unmolten minerals deep below the volcano. These meteorite lavas should behave the same way. During my student days in the 1970s, we calculated that that for every basaltic meteorite, there should be about four times as much … Continue reading

Revealed Through Reason: The Phases of the Jovian Moons
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In 1614 Johann Georg Locher, a student of the Jesuit astronomer Fr. Christoph Scheiner, published a short book called Disquisitiones mathematicae, de controversiis et novitatibus astronomicis—that is, Mathematical Disquisitions, Concerning Astronomical Controversies and Novelties. Among other things, the book discussed the phases of Venus and the satellites of Jupiter, all recently discovered by Galileo using a telescope. Toward the end of the book, Locher engaged in an interesting exercise in astronomical reasoning. He presented to his readers the figure below. And, regarding this figure, he wrote— Vnam hactenus Lunam agnouimus circa terram, quam oculus A in terra positus libere conspexit, modo silentem in B; modo dimidiam in C; alias plenam in D; alias curtatam in E…. At vero, post repertum Oculum Astronomicum, tubum inquam Opticum, plures sese aperuerunt nobis Lunae.   Quarum praecipua videtur esse Venus; ea enim in tubum GH ex I delapsa, oculo A occurrit falcata, dum puncto M Augis opposito vicina agit: & vero in K Auge … Continue reading

Rhapsody in Blue – Saturn / Moon Occultation
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On the evening of May 22nd 2007 the beautiful blue sky was host to a first quarter moon. The evening was to bring me one of the most visually rich observations in my drawing odyssey . When I set up my dob I really wasn’t expecting to  catch a glimpse of Saturn in a daylight sky. The software gave me an idea of where the planet was, I scanned the area in the hope of finding it. My task was to see Saturn before it went behind the unlit quarter of the moon. In my first look there it was, the white ringed planet, one billion miles away in space. Saturn was there in my eye, embedded softly in the azure sky moving swiftly toward  the invisible limb of the moon.  Nothing could have prepared me for that  revelation, it was a totally different experience to seeing Saturn in a dark night sky. My drawing paper was hastily endowed in blue … Continue reading

Across the Universe: Maybe
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  This column first ran in The Tablet in April 2013 The Kepler Space Telescope, monitoring a hundred thousand stars to catch the faint flickers of light that might indicate the shadows of planets, announced [April 2013] the discovery of a star that may have two super-Earths orbiting within its “Goldilocks zone.” That’s the distance from the star where liquid water should be stable. The idea of a system with two planets that could harbor life brings up all sorts of exciting science-fictional possibilities. Well, maybe. We don’t know for sure yet that either planet really is Earth-like; they could be small gas balls. We don’t know yet if either planet has an atmosphere, much less the sorts of chemicals we associate with life. And after all, our own solar system has two bodies within its Goldilocks zone – Earth and its Moon – but only one has life. For that matter, Mars is close enough to that stable zone … Continue reading

Cosmic Lobster Pot
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I have always visualised Cassini’s journey through the Saturnian system as a kind of orchestrated cosmic dance. Cassini moves silently at great speed in its petal shape overlapping orbits. This precisely executed dance brings Cassini frequently through the icy ring plane north to south and then back again on the opposite side of the planet, south to north. This robot ship continues on its unparalleled odyssey of exploration. On board, Cassini is the custodian of twelve science instruments all primed to seek, gather, and process the offerings of this unique planetary system. Collectively they are performing one of the most important scientific probing of Saturn and its many moons in the history of space exploration. One of these science instruments is the Cosmic Dust Analyser. The CDA looks a bit like a golden lobster pot,that is not a bad analogy. This apparatus is trawling the interplanetary ocean for particles of cosmic dust, tiny particles that are the messengers of the … Continue reading

Across the Universe: Words, Words, Worlds
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Originally published in The Tablet in March, 2004 – the first of many columns I wound up writing about the definition of a planet, leading up to the IAU decision about Pluto in 2006. And this is a repeat of a blog entry first published at the Catholic Astronomer three years ago… as I have run out of Tablet columns to publish! On the other side of Neptune live the Trans-Neptunian Objects, or TNOs. They are worlds so faint that to measure their colors, we use a mirror nearly two meters across to gather their light, which we focus into a spot of only a few hundreds of a millimeter, collecting it with an ultra-sensitive electronic chip, over a five-minute time exposure. They move – more than five minutes and the spot turns into a streak. But take enough exposures over a few hours and you can plot their motions against the background stars and galaxies. The TNOs are thought to be the … Continue reading

Across the Universe: Spotting Ceres
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This column first ran in The Tablet in March 2015 Ceres was the first body found in the region between Mars and Jupiter now called the Asteroid Belt. In the late 1700s Titius and Bode had noted a pattern in planet positions that suggested there should be a planet in the gap between Mars and Jupiter; on New Year’s Day of 1801, Father Giuseppi Piazzi found Ceres from his observatory in Sicily. They expected a planet, so that’s what they called Ceres – though William Herschel, who had just discovered the gas giant Uranus, sniffed that such a tiny dot of light was neither planet nor star (Latin, “aster”) but a mere “asteroid.” Only fifty years later, when a number of other such small bodies had been found, did Ceres and the other asteroids get “demoted” to the status of “minor planet.” (And later work showed that the Titius-Bode pattern which predicted a planet at Ceres’ position was actually just … Continue reading

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