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Posts Tagged ‘astronomy

“By preventing dangerous asteroid strikes, we can save millions of people, or even our entire species”*…

The probability of an major asteroid strike on earth at any given moment is low, but the consequences could be catastrophic… and the odds of it happening at some point grow frighteningly large. Happily, the B612 Foundation and Asteroid Institute has developed a way of identifying potentially dangerous asteroids so that they can be deflected by NASA…

Protecting the planet: The Asteroid Institute, @b612foundation.

* Rusty Schweickart, astronaut and co-founder of B612

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As we dodge disaster, we might recall that it was on this date in 1957 that the space age– and the space race– began in earnest: Sputnik 1 was launched by the Soviet Union into earth orbit.

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Written by (Roughly) Daily

October 4, 2022 at 1:00 am

“To achieve style, begin by affecting none”*…

The first issue of the Philosophical Transactions of the Royal Society

From Roger’s Bacon, in New Science, a brief history of scientific writing…

Since the founding of the first scientific journal in 1665, there have been calls to do away with stylistic elements in favor of clarity, concision, and precision.

In 1667, Thomas Sprat urged members of the Royal Society to “reject all the amplifications, digressions, and swellings of style; to return back to the primitive purity, and shortness, when men delivered so many things, almost in an equal number of words.” Some 200 years later, Charles Darwin said much the same: “I think too much pains cannot be taken in making the style transparently clear and throwing eloquence to the dogs” (Aaronson, 1977).

Darwin and Sprat eventually got their way. Modern scientific writing is homogenous, cookie-cutter, devoid of style. But scientific papers weren’t always like this.

Writing in The Last Word On Nothing blog, science journalist Roberta Kwok explains how old articles differ from their modern counterparts:

Scientists used to admit when they don’t know what the hell is going on.

When philosopher Pierre Gassendi tried to capture observations of Mercury passing in front of the Sun in 1631, he was beset by doubts:

“[T]hrown into confusion, I began to think that an ordinary spot would hardly pass over that full distance in an entire day. And I was undecided indeed… I wondered if perhaps I could not have been wrong in some way about the distance measured earlier.”

They get excited and use italics.

In 1892, a gentleman named William Brewster observed a bird called a northern shrike attacking a meadow mouse in Massachusetts. After tussling with its prey, he wrote, “[t]he Shrike now looked up and seeing me jumped on the mouse with both feet and flew off bearing it in its claws.”

They write charming descriptions.

Here’s French scientist Jean-Henri Fabre rhapsodizing about the emperor moth in his book, The Life of the Caterpillar (1916):

Who does not know the magnificent Moth, the largest in Europe, clad in maroon velvet with a necktie of white fur? The wings, with their sprinkling of grey and brown, crossed by a faint zig-zag and edged with smoky white, have in the centre a round patch, a great eye with a black pupil and a variegated iris containing successive black, white, chestnut and purple arcs.

All this to say: Scientists in the pre-modern era wrote freely, despite calls to do away with that freedom. At some point, narrative and literary styles vanished and were replaced with rigid formats and impoverished prose.  The question now is: Have we gone too far in removing artistry from scientific writing?

For a well-argued case that we have– “the way that we write is inseparable from the way that we think, and restrictions in one necessarily lead to restrictions in the other”– read on: “Research Papers Used to Have Style. What Happened?,” from @RogersBacon1 and @newscienceorg.

* E. B. White, The Elements of Style

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As we ponder purposive prose, we might spare a thought for Johann Adam Schall von Bell; he died on this date in 1666. An expressive writer in both German and Chinese, he was an astronomer and Jesuit missionary to China who revised the Chinese calendar, translated Western astronomical books, and was head of Imperial Board of Astronomy (1644-64). Given the Chinese name “Tang Ruowang,” he became a trusted adviser (1644-61) to Emperor Shun-chih, first emperor of the Ch’ing dynasty (1644-1911/12), who made him a mandarin.

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“‘Space-time’ – that hideous hybrid whose very hyphen looks phoney”*…

Space-time curvature [source: ESA]

Space and time seem about as basic as anything could be, even after Einstein’s theory of General Relativity threw (in) a curve. But as Steven Strogatz discusses with Sean Carroll, the reconciliation of Einstein’s work with quantum theory is seeming to suggest that space and time might actually be emergent properties of quantum reality, not fundamental parts of it…

… we’re going to be discussing the mysteries of space and time, and gravity, too. What’s so mysterious about them?

Well, it turns out they get really weird when we look at them at their deepest levels, at a super subatomic scale, where the quantum nature of gravity starts to kick in and become crucial. Of course, none of us have any direct experience with space and time and gravity at this unbelievably small scale. Up here, at the scale of everyday life, space and time seem perfectly smooth and continuous. And gravity is very well described by Isaac Newton’s classic theory, a theory that’s been around for over 300 years now.

But then, about 100 years ago, things started to get strange. Albert Einstein taught us that space and time could warp and bend like a piece of fabric. This warping of the space-time continuum is what we experience as gravity. But Einstein’s theory is mainly concerned with the largest scales of nature, the scale of stars, galaxies and the whole universe. It doesn’t really have much to say about space and time at the very smallest scales.

And that’s where the trouble really starts. Down there, nature is governed by quantum mechanics. This amazingly powerful theory has been shown to account for all the forces of nature, except gravity. When physicists try to apply quantum theory to gravity, they find that space and time become almost unrecognizable. They seem to start fluctuating wildly. It’s almost like space and time fall apart. Their smoothness breaks down completely, and that’s totally incompatible with the picture in Einstein’s theory.

s physicists try to make sense of all of this, some of them are coming to the conclusion that space and time may not be as fundamental as we always imagined. They’re starting to seem more like byproducts of something even deeper, something unfamiliar and quantum mechanical. But what could that something be?….

Find out at: “Where Do Space, Time and Gravity Come From?, ” from @stevenstrogatz and @seanmcarroll in @QuantaMagazine.

* Vladimir Nabokov

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As we fumble with the fundamental, we might send far-sighted birthday greetings to Jocelyn Bell Burnell; she was born on this date in 1943. An astrophysicist, she discovered the first pulsar, while working as a post-doc, in 1957. She then discovered the next three detected pulsars.

The discovery eventually earned the Nobel Prize in Physics in 1974; however, she was not one of the prize’s recipients. The paper announcing the discovery of pulsars had five authors. Bell’s thesis supervisor Antony Hewish was listed first, Bell second. Hewish was awarded the Nobel Prize, along with the astronomer Martin Ryle.

A pulsar— or pulsating radio star– a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation. The precise periods of pulsars make them very useful tools. Observations of a pulsar in a binary neutron star system were used to  confirm (indirectly) the existence of gravitational radiation. The first extrasolar planets were discovered around a pulsar, PSR B1257+12.  And certain types of pulsars rival atomic clocks in their accuracy in keeping time.

Schematic rendering of a pulsar

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Jocelyn Bell Burnell

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Written by (Roughly) Daily

July 15, 2022 at 1:00 am

“The commonality between science and art is in trying to see profoundly – to develop strategies of seeing and showing”*…

Working with her scientist husband, Orra Hitchcock produced illustrations on bolts of linen that manifest original knowledge about extinction, stratigraphy, and their evidentiary features in the surrounding landscape– and trained eager young students to recognize and describe geological and natural-historical phenomena…

After meeting and falling in love with Edward Hitchcock, her employer at Massachusetts’ Deerfield Academy, Orra (née White) married him in 1821, beginning a lifetime of professional collaboration while raising a family amid piles of rocks and research tomes. Highly trained, white, and wealthy, she was far from an oddity in nineteenth-century education. Like many other women of her class, Hitchcock received extensive instruction in the arts and sciences, making a name by working alongside, not beneath, a man who had easier access to academic opportunities. Variously lauded as “an anomaly” and “the most remarkable” of their era, her scientific illustrations have rarely been considered on their own terms — admired for the natural historical and religious knowledge they contain — without being made an exemplar of the broader category of “women’s work”.

Moving to Amherst when Edward was appointed Professor of Chemistry and Natural History, the couple embarked on a decades-long exploration of the Connecticut River Valley’s botany and geology. While Edward lectured to eager young students about the principles of nature, from the depths of oceans to the granite veins of the earth, Orra produced more than sixty hand-colored scientific illustrations on poster-sized linen swaths designed to be hung on classroom walls.

Ranging from extinct mammals like Megatherium (a genus of giant ground sloth [below]) through lithic strata to fossilized footprints, the collection is striking for its modern abstraction, anticipating the later works of George Maw. Although some of Hitchcock’s geological illustrations seem far from “accurate” in their specificity (or lack thereof), her devotion to clear and concise visual communication bespeaks a deep-seated understanding of complex scientific principles…

An appreciation: “Orra White Hitchcock’s Scientific Illustrations for the Classroom (1828–40),” from @PublicDomainRev.

* Edward Tufte

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As we picture it, we might send sharply-observant birthday greetings to Cecilia Helena Payne-Gaposchkin; she was born on this date in 1900.  An astrophysicist and astronomer, she was the first– in her Radcliffe (Harvard) PhD thesis in 1927– to apply the laws of atomic physics to the study of the temperature and density of stellar bodies: the first to conclude that hydrogen and helium are the two most common elements in the universe and the first to suggest that the Sun is primarily (99%) composed of hydrogen.  During the 1920s, the accepted explanation of the Sun’s composition was a calculation of around 65% iron and 35% hydrogen.  Her thesis adviser, astronomer Henry Norris Russell, reached a similar conclusion via his own observations several years later, and (while he made brief mention of Payne’s work) was for a time credited with the discovery.  But in 1947, astronomer Fred Hoyle confirmed her original claim.

She spent her entire career at Harvard.  In 1956 she became the first woman to be promoted to full professor from within the faculty at Harvard’s Faculty of Arts and Sciences. Later, with her appointment to the Chair of the Department of Astronomy, she also became the first woman to head a department at Harvard.

Her students included Helen Sawyer Hogg, Joseph AshbrookPaul W. Hodge, and Frank Drake (the creator of the Drake Equation)– all of whom made important contributions to astronomy.

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“Werner Heisenberg once proclaimed that all the quandaries of quantum mechanics would shrivel up when 137 was finally explained”*…

One number to rule them all?

Does the Universe around us have a fundamental structure that can be glimpsed through special numbers?

The brilliant physicist Richard Feynman (1918-1988) famously thought so, saying there is a number that all theoretical physicists of worth should “worry about”. He called it “one of the greatest damn mysteries of physics: a magic number that comes to us with no understanding by man.”

That magic number, called the fine structure constant, is a fundamental constant, with a value which nearly equals 1/137. Or 1/137.03599913, to be precise. It is denoted by the Greek letter alpha – α.

What’s special about alpha is that it’s regarded as the best example of a pure number, one that doesn’t need units. It actually combines three of nature’s fundamental constants – the speed of light, the electric charge carried by one electron, and the Planck’s constant, as explains physicist and astrobiologist Paul Davies to Cosmos magazine. Appearing at the intersection of such key areas of physics as relativity, electromagnetism and quantum mechanics is what gives 1/137 its allure…

The fine structure constant has mystified scientists since the 1800s– and might hold clues to the Grand Unified Theory: “Why the number 137 is one of the greatest mysteries in physics,” from Paul Ratner (@paulratnercodex) in @bigthink.

* Leon M. Lederman, The God Particle: If the Universe Is the Answer, What Is the Question?

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As we ruminate on relationships, we might spare a thought for Georg von Peuerbach; he died on this date in 1461. A mathematician, astronomer, and instrument maker, he is probably best remembered for his streamlined presentation of Ptolemaic astronomy in the Theoricae Novae Planetarum (which was an important text for many later-influential astronomers including Nicolaus Copernicus and Johannes Kepler).

But perhaps as impactful was his promotion of the use of Arabic numerals (introduced 250 years earlier in place of Roman numerals), especially in a table of sines he calculated with unprecedented accuracy.

Georg von Peuerbach: Theoricarum novarum planetarum testus, Paris 1515 [source]
Page from Peurbach’s sine table [source]
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