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Posts Tagged ‘astronomy

“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]

“No part of mathematics is ever, in the long run, ‘useless’.”*…

The number 1 can be written as a sum of distinct unit fractions, such as 1/2 + 1/3 + 1/12 + 1/18 + 1/36…

Number theorists are always looking for hidden structure. And when confronted by a numerical pattern that seems unavoidable, they test its mettle, trying hard — and often failing — to devise situations in which a given pattern cannot appear.

One of the latest results to demonstrate the resilience of such patterns, by Thomas Bloom of the University of Oxford, answers a question with roots that extend all the way back to ancient Egypt.

“It might be the oldest problem ever,” said Carl Pomerance of Dartmouth College.

The question involves fractions that feature a 1 in their numerator, like 1/2, 1/7 or 1/122. These “unit fractions” were especially important to the ancient Egyptians because they were the only types of fractions their number system contained: With the exception of a single symbol for 23, they could only express more complicated fractions (like 3/4) as sums of unit fractions (1/2 + 1/4).

The modern-day interest in such sums got a boost in the 1970s, when Paul Erdős and Ronald Graham asked how hard it might be to engineer sets of whole numbers that don’t contain a subset whose reciprocals add to 1. For instance, the set {2, 3, 6, 9, 13} fails this test: It contains the subset {2, 3, 6}, whose reciprocals are the unit fractions 1/2, 1/3 and 1/6 — which sum to 1.

More exactly, Erdős and Graham conjectured that any set that samples some sufficiently large, positive proportion of the whole numbers — it could be 20% or 1% or 0.001% — must contain a subset whose reciprocals add to 1. If the initial set satisfies that simple condition of sampling enough whole numbers (known as having “positive density”), then even if its members were deliberately chosen to make it difficult to find that subset, the subset would nonetheless have to exist.

“I just thought this was an impossible question that no one in their right mind could possibly ever do,” said Andrew Granville of the University of Montreal. “I didn’t see any obvious tool that could attack it.”…

Bloom, building on work by Ernie Croot, found that tool. The ubiquity of ways to represent whole numbers as sums of fractions: “Math’s ‘Oldest Problem Ever’ Gets a New Answer,” by Jordana Cepelewicz (@jordanacep) in @QuantaMagazine.

* “No part of mathematics is ever, in the long run, ‘useless.’ Most of number theory has very few ‘practical’ applications. That does not reduce its importance, and if anything it enhances its fascination. No one can predict when what seems to be a most obscure theorem may suddenly be called upon to play some vital and hitherto unsuspected role.” – C. Stanley Ogilvy, Excursions in Number Theory

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As we recombine, we might send carefully-calculated birthday greetings to Ulugh Beg (or, officially, Mīrzā Muhammad Tāraghay bin Shāhrukh); he was born on this date in 1394. A Timurid sultan with a hearty interest in science and the arts, he is better remembered as an astronomer and mathematician.

The most important observational astronomer of the 15th century, he built the great Ulugh Beg Observatory in Samarkand between 1424 and 1429– considered by scholars to have been one of the finest observatories in the Islamic world at the time and the largest in Central Asia. In his observations he discovered a number of errors in the computations of the 2nd-century Alexandrian astronomer Ptolemy, whose figures were still being used. His star map of 994 stars was the first new one since Hipparchus. Among his contributions to mathematics were trigonometric tables of sine and tangent values correct to at least eight decimal places.

Ulugh Beg’s Statue in Samarkand, Uzbekistan

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“Eventually everything connects”*…

Long-time readers will know of your correspondent’s fascination with Powers of Ten, a remarkable short film by Charles and Ray Eames, with Philip Morrison, that begins with a couple having a picnic, zooms out by “powers of ten” to the edge of the universe, then zooms in (by those same increments) to a proton.

We’ve looked before at a number of riffs on this meditation on scale: see, e.g., here, here, and here.

Now the BBC has updated the first half of Powers of Ten:

It’s a trip worth taking.

* Charles Eames

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As we wrestle with relationships, we might light a birthday candle for Sir Francis Bacon– English Renaissance philosopher, lawyer, linguist, composer, mathematician, geometer, musician, poet, painter, astronomer, classicist, philosopher, historian, theologian, architect, father of modern science (The Baconian– aka The Scientific– Method), and patron of modern democracy, whom some allege was the illegitimate son of Queen Elizabeth I of England (and others, the actual author of Shakespeare’s plays)… He was in any event born on this date in 1561.

Bacon (whose Essays were, in a fashion, the first “management book” in English) was, in Alexander Pope’s words, “the greatest genius that England, or perhaps any country, ever produced.”  He probably did not actually write the plays attributed to Shakespeare (as a thin, but long, line of enthusiasts, including Mark Twain and Friedrich Nietzsche, believed).  But Bacon did observe, in a discussion of sedition that’s as timely today as ever, that “the remedy is worse than the disease.”

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“Any sufficiently advanced technology is equivalent to magic”*…

In the 1930s, ATT was rolling out dial phones to the American public…

This short subject newsreel was shown in movie theaters the week before a town’s or region’s telephone exchange was to be converted to dial service. It’s extremely short—a little over a minute, like a PSA. The film concisely explains how to use a dial telephone, including how to dial, how to recognize dial tone, and how to recognize a busy signal…

For a look into the then-future (the now present), fast forward just over 50 years, to the early 90s and to ATT’s predictions…

More in ATT Tech Channel.

[TotH to @BoingBoing for a pointer to the first video]

* Arthur C. Clarke (a 1976 interview with whom is in the Tech Channel trove)

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As we ponder progress, we might send , ATT-related birthday greetings to Robert Woodrow Wilson; he was born on this date in 1936.  An astronomer, he detected– with Bell Labs colleague Arno Penzias– cosmic microwave background radiation: “relic radiation”– that’s to say, the “sound “– of the Big Bang…. familiar to those of old enough to remember watching an old-fashioned television after the test pattern was gone (when there was no broadcast signal received): the “fuzz” we saw and the static-y sounds we heard, were the “relic radiation” being picked up.

Their 1964 discovery earned them the 1978 Nobel Prize in Physics.

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