Tag: Saturday Night Science

Contributor Post Created with Sketch. Saturday Night Science: The Army’s Flying Saucer


Avro Canada VZ-9 AvrocarThe 1950s and 1960s were a time of great innovation in aircraft design. Speed records were set and shattered on a regular basis, and all kinds of innovative, or some may say, crazy designs were explored. One of the most curious of these was the Avro Canada VZ-9 Avrocar, which was literally a flying saucer. Developed by Avro Aircraft, Ltd. of Canada, it was initially supported by the US Air Force as an advanced fighter aircraft, and after it became clear it would never meet its performance goals, was funded by the US Army, which saw it as a kind of flying Jeep, replacing helicopters for operations in rough terrain.

The design was very odd. Lift for vertical takeoff and landing was provided by a central “turbo-rotor” with fan blades which created downward thrust. The rotor was powered by three jet engines mounted in the fuselage, but they were not mechanically coupled to the rotor like the engines in a helicopter. Instead, their jet blast was directed at turbine blades attached to the rotor, which caused it to spin. A portion of the rotor’s thrust was diverted to thrusters mounted around the periphery of the vehicle which the pilot could use to orient in pitch, roll, and yaw. Later special ports were added to the aft end of the craft to produce thrust intended to allow it to transition from hovering to forward flight.


Contributor Post Created with Sketch. Saturday Night Science: The Cosmic Web


“The Cosmic Web” by J. Richard GottSome works of popular science, trying to impress the reader with the scale of the universe and the insignificance of humans on the cosmic scale, argue that there’s nothing special about our place in the universe: “an ordinary planet orbiting an ordinary star, in a typical orbit within an ordinary galaxy,” or something like that. But this is wrong! Surfaces of planets make up a vanishingly small fraction of the volume of the universe, and habitable planets, where beings like ourselves are neither frozen nor fried by extremes of temperature, nor suffocated or poisoned by a toxic atmosphere, are rarer still. The Sun is far from an ordinary star: it is brighter than 85% of the stars in the galaxy, and only 7.8% of stars in the Milky Way share its spectral class. Fully 76% of stars are dim red dwarves, the heavens’ own 25 watt bulbs.

What does a typical place in the universe look like? What would you see if you were there? Well, first of all, you’d need a space suit and air supply, since the universe is mostly empty. And you’d see nothing. Most of the volume of the universe consists of great voids with few galaxies. If you were at a typical place in the universe, you’d be in one of these voids, probably far enough from the nearest galaxy that it wouldn’t be visible to the unaided eye. There would be no stars in the sky, since stars are only formed within galaxies. There would only be darkness. Now look out the window: you are in a pretty special place after all.


Contributor Post Created with Sketch. Saturday Night Science: Black Hole Blues

LIGO Hanford Observatory
Aerial photo of the LIGO Hanford Observatory. Public domain image by the LIGO Scientific Collaboration.

In Albert Einstein’s 1915 general theory of relativity, gravitation does not propagate instantaneously as it did in Newton’s theory, but at the speed of light. According to relativity, nothing can propagate faster than light. This has a consequence which was not originally appreciated when the theory was published: if you move an object here, its gravitational influence upon an object there cannot arrive any faster than a pulse of light traveling between the two objects. But how is that change in the gravitational field transmitted? For light, it is via the electromagnetic field, which is described by Maxwell’s equations and implies the existence of excitations of the field which, according to their wavelength, we call radio, light, and gamma rays. Are there, then, equivalent excitations of the gravitational field (which, according to general relativity, can be thought of as curvature of spacetime), which transmit the changes due to motion of objects to distant objects affected by their gravity and, if so, can we detect them? By analogy to electromagnetism, where we speak of electromagnetic waves or electromagnetic radiation, these would be gravitational waves or gravitational radiation.

Einstein first predicted the existence of gravitational waves in a 1916 paper, but he made a mathematical error in the nature of sources and the magnitude of the effect. This was corrected in a paper he published in 1918 which describes gravitational radiation as we understand it today. According to Einstein’s calculations, gravitational waves were real, but interacted so weakly that any practical experiment would never be able to detect them. If gravitation is thought of as the bending of spacetime, the equations tell us that spacetime is extraordinarily stiff: when you encounter an equation with the speed of light, c, raised to the fourth power in the denominator, you know you’re in trouble trying to detect the effect.


Contributor Post Created with Sketch. Saturday Night Science: Fractal Food


Self-Similarity on the Supermarket Shelf

Romanesco (broccoli/caulifower/cabbage family vegetable)Fractal forms—complex shapes which look more or less the same at a wide variety of scale factors, are everywhere in nature. From the fluctuations in the cosmic microwave background radiation to the coastlines of continents, courses of rivers, clouds in the sky, branches of plants and veins in their leaves, blood vessels in the lung, and the shape of seashells and snowflakes, these fractal or self-similar patterns abound. The self-similarity of most of these patterns is defined only in a statistical sense: while the general “roughness” is about the same at different scales, you can’t extract a segment, blow it up, and find a larger scale segment which it matches precisely.

However, some of the most pleasing patterns in geometric art exhibit exact or almost exact self-similarity. These are patterns which are composed of smaller copies of themselves ad infinitum, or at least until some limit where the similarity breaks down due to the granularity of the underlying material.


Contributor Post Created with Sketch. Saturday Night Science: Coming Home


“Coming Home” by Roger D. Launius and Dennis R. JenkinsIn the early decades of the 20th century, when visionaries such as Konstantin Tsiolkovsky, Hermann Oberth, and Robert H. Goddard started to think seriously about how space travel might be accomplished, most of the focus was on how rockets might be designed and built which would enable their payloads to be accelerated to reach the extreme altitude and velocity required for long-distance ballistic or orbital flight.

This is a daunting problem. The Earth has a deep gravity well: so deep that to place a satellite in a low orbit around it, you must not only lift the satellite from the Earth’s surface to the desired orbital altitude (which isn’t particularly difficult), but also impart sufficient velocity to it so that it does not fall back but, instead, orbits the planet. It’s the speed that makes it so difficult.


Contributor Post Created with Sketch. Saturday Night Science: Obsessive Genius


Obsessive GeniusMaria Salomea Skłodowska was born in 1867 in Warsaw, Poland, then part of the Russian Empire. She was the fifth and last child born to her parents, Władysław and Bronisława Skłodowski, both teachers. Both parents were members of a lower class of the aristocracy called the Szlachta, but had lost their wealth through involvement in the Polish nationalist movement opposed to Russian rule. They retained the love of learning characteristic of their class, and had independently obtained teaching appointments before meeting and marrying. Their children were raised in an intellectual atmosphere, with their father reading books to them in Polish, Russian, French, German, and English, all languages in which he was fluent.

During Maria’s childhood, her father lost his teaching position after his anti-Russian sentiments and activities were discovered, and supported himself by operating a boarding school for boys from the provinces. In cramped and less than sanitary conditions, one of the boarders infected two of the children with typhus: Marie’s sister Zofia died. Three years later, her mother, Bronisława, died of tuberculosis. Maria experienced her first episode of depression, a malady which would haunt her throughout life.


Contributor Post Created with Sketch. Saturday Night Science: Transit of Mercury, May 9th, 2016

Transit of Mercury, 2003-05-07
Transit of Mercury, 2003-05-07. Public domain photo by John Walker.

One month from today, on Monday, May 9, a rare celestial spectacle will be visible from most of the world. The planet Mercury, closest to the Sun, will pass in front of the Sun’s disc as seen from the Earth: a transit of Mercury.

These events are rather uncommon. Because Mercury’s orbit is inclined 7° with respect to the plane of the ecliptic (that is defined by the Earth’s orbit), a transit only occurs when Mercury comes to inferior conjunction (closest to the Earth) at close to the time when its orbit is crossing the ecliptic (when it is at its ascending or descending node). At present, transits of Mercury occur only in May and November. The most recent transit was in November 2006, and the next transit after this year’s will be on Nov. 11, 2019. If you miss that one, you’ll have to wait until November 13, 2032, for the next.


Contributor Post Created with Sketch. Saturday Night Science: Flying Saucers Explained


Animated cartoon of a flying saucerPrologue

Suppose that we find no radio messages traveling through space, transmitted by extraterrestrial civilizations for our enlightenment. Suppose that we fail to find traces of life anywhere outside our own planet. What then would be the minimum modifications that would have to be imposed upon terrestrial life to enable us to make good nature’s lack? Now that genetic engineering is rapidly becoming a practical proposition, it is not absurd to think of redesigning terrestrial creatures so as to make them viable in space or on other celestial bodies. — Freeman Dyson


Jack Sarfatti has been exploring a generalisation of David Bohm’s[4] ontological interpretation of quantum mechanics, extended so a particle is not just guided by the quantum potential, but, in turn, through backactivity, modifies the quantum potential field. Backactivity introduces nonlinearity into the evolution of the wave function, much like the bidirectional nonlinear interaction of spacetime and matter-energy in general relativity.


Contributor Post Created with Sketch. Saturday Night Science: How the Hippies Saved Physics


hipFrom its origin in the early years of the 20th century until the outbreak of World War II, quantum theory inspired deeply philosophical reflection as to its meaning and implications for concepts rarely pondered before in physics, such as the meaning of “measurement,” the role of the “observer,” the existence of an objective reality apart from the result of a measurement, and whether the randomness of quantum measurements was fundamental or due to our lack of knowledge of an underlying stratum of reality.

Quantum theory seemed to imply that the universe could not be neatly reduced to isolated particles which interacted only locally, but admitted “entanglement” among separated particles which seemed to verge upon mystic conceptions of “all is one.” These weighty issues occupied the correspondence and conference debates of the pioneers of quantum theory including Planck, Heisenberg, Einstein, Bohr, Schrödinger, Pauli, Dirac, Born, and others.


Contributor Post Created with Sketch. Saturday Night Science: Thing Explainer


“Thing Explainer” by Randall MunroeWhat a great idea! The person who wrote this book explains not simple things like red world sky cars, tiny water bags we are made of, and the shared space house, all with only the ten hundred words people use most.

There are many pictures with words explaining each thing. The idea came from the Up Goer Five picture he drew earlier. The drawing is in two parts so you can read it clearly. (If the parts do not line up, make your window wider.)


Contributor Post Created with Sketch. Saturday Night Science: Energiya-Buran


“Energiya-Buran” by Bart Hendrickx and Bert VisThis authoritative history chronicles one of the most bizarre episodes of the Cold War. When the US Space Shuttle program was launched in 1972, the Soviets, unlike the majority of journalists and space advocates in the West who were bamboozled by NASA’s propaganda, couldn’t make any sense of the economic justification for the program. They crunched the numbers, and they just didn’t work—the flight rates, cost per mission, and most of the other numbers were obviously not achievable.

So, did the Soviets chuckle at this latest folly of the capitalist, imperialist aggressors and continue on their own time-proven path of mass-produced low-technology expendable boosters? Well, of course not! They figured that even if their wisest double-domed analysts were unable to discern the justification for the massive expenditures NASA had budgeted for the Shuttle, there must be some covert military reason for its existence to which they hadn’t yet twigged, and hence they couldn’t tolerate a shuttle gap and consequently had to build their own, however pointless it looked on the surface.


Contributor Post Created with Sketch. Saturday Night Science: Nitrogen Triiodide

Space-filling model of Nitrogen Triiodide molecule
Space-filling model of Nitrogen Triiodide molecule. (Public domain image by Wikimedia user Benjah-bmm27.)

One fine day during my years at engineering school I was walking down the stairs between two floors in the chemistry building. Bang! It sounded like a gunshot, and close at hand. I was alone in the stairwell, and a quick inventory showed no punctures, so I shrugged it off and continued down the stairs. Just one of those things …

A few steps later, bang! By the time I reached the landing, there had been two additional loud reports. It’s then that I noticed there were dark splotchy purple-red stains on some of the stairs. I went back up a couple of stairs and deliberately stepped on one: bang, and a purple cloud shot from around my shoe and started to disperse.


Contributor Post Created with Sketch. Saturday Night Science: Tesla


“Tesla” by W. Bernard CarlsonNicola Tesla was born in 1858 in a village in what is now Croatia, then part of the Austro-Hungarian Empire. His father and grandfather were both priests in the Orthodox church. The family was of Serbian descent, but had lived in Croatia since the 1690s among a community of other Serbs. His parents wanted him to enter the priesthood and enrolled him in school to that end. He excelled in mathematics and, building on a boyhood fascination with machines and tinkering, wanted to pursue a career in engineering. After completing high school, Tesla returned to his village where he contracted cholera and was near death. His father promised him that if he survived, he would “go to the best technical institution in the world.” After nine months of illness, Tesla recovered and, in 1875 entered the Joanneum Polytechnic School in Graz, Austria.

Tesla’s university career started out brilliantly, but he came into conflict with one of his physics professors over the feasibility of designing a motor which would operate without the troublesome and unreliable commutator and brushes of existing motors. He became addicted to gambling, lost his scholarship, and dropped out in his third year. He worked as a draftsman, taught in his old high school, and eventually ended up in Prague, intending to continue his study of engineering at the Karl-Ferdinand University. He took a variety of courses, but eventually his uncles withdrew their financial support.


Contributor Post Created with Sketch. Saturday Night Science: Strange Angel


“Strange Angel” by George PendleFor those who grew up after World War II “rocket science” meant something extremely difficult, on the very edge of the possible, pursued by the brightest of the bright, often at risk of death or dire injury. In the first half of the century, however, “rocket” was a pejorative, summoning images of pulp magazines full of “that Buck Rogers stuff”, fireworks that went fwoosh—flash—bang if all went well, and often in the other order when it didn’t, with aspiring rocketeers borderline lunatics who dreamed of crazy things like travelling to the Moon but usually ended blowing things up, including, but not limited to, themselves.

This was the era in which John Whiteside “Jack” Parsons came of age. Parsons was born and spent most of his life in Pasadena, California, a community close enough to Los Angeles to participate in its frontier, “anything goes” culture, but also steeped in well-heeled old wealth, largely made in the East and seeking the perpetually clement climate of southern California. Parsons was attracted to things that went fwoosh and bang from the very start. While still a high school senior, he was hired by the Hercules Powder Company, and continued to support himself as an explosives chemist for the rest of his life. He never graduated from college, no less pursued an advanced degree, but his associates and mentors, including legends such as Theodore von Kármán were deeply impressed by his knowledge and meticulously careful work with dangerous substances and gave him their highest recommendations. On several occasions he was called as an expert witness to testify in high-profile trials involving bombings.


Contributor Post Created with Sketch. Saturday Night Science: The Wright Brothers


“The Wright Brothers” by David McCulloughOn December 8, 1903, all was in readiness. The aircraft was perched on its launching catapult, the brave airman at the controls. The powerful internal combustion engine roared to life. At 16:45 the catapult hurled the craft into the air. It rose straight up, flipped, and — with its wings coming apart — plunged into the Potomac river just 20 feet from the launching point. The pilot was initially trapped beneath the wreckage but managed to free himself and swim to the surface. After being rescued from the river, he emitted what one witness described as “the most voluble series of blasphemies” he had ever heard.

So ended the last flight of Samuel Langley’s “Aerodrome.” Langley was a distinguished scientist and secretary of the Smithsonian Institution in Washington D.C. Funded by the U.S. Army and the Smithsonian for a total of $70,000 (equivalent to around $1.7 million today), the Aerodrome crashed immediately on both of its test flights and was the subject of much mockery in the press.


Contributor Post Created with Sketch. Saturday Night Science: Pitch Drop

Pitch drop experiment from the University of Queensland, Australia
Pitch drop experiment at the University of Queensland, Australia. Image licensed under CC BY-SA 3.0.

Viscosity is a measure of how strongly a fluid resists gradual deformation. Fluids with higher viscosity such as honey are thought of as “thicker” than less viscous fluids like water. The range of viscosities in liquids is enormous. Superfluids, such as Helium-II, have zero viscosity. Honey is between 2,000 and 10,000 times more viscous than water. Some fluids are so viscous they appear to be solid and yet, over time, slowly flow.

One of the most viscous liquids known is pitch, also known as bitumen, asphalt, or tar. Demonstrating its flow and measuring its viscosity is the subject of the longest continuously running scientific experiment, begun in 1927 at the University of Queensland in Australia. Prof. Thomas Parnell heated pitch (which dramatically decreases its viscosity), then poured it into a funnel with a sealed bottom. After three years (to allow the pitch to settle), the bottom of the funnel was removed and the funnel placed in a bell jar with a beaker below it. The pitch slowly flows out of the funnel, forming a large drop. About every decade a drop falls off into the beaker.


Contributor Post Created with Sketch. Saturday Night Science: Monsters


“Monsters” by Ed RegisAs the American Civil War raged, Count Ferdinand von Zeppelin, an ambitious young cavalry officer from the German kingdom of Württemberg, arrived in America to observe the conflict and learn its lessons for modern warfare. He arranged an audience with President Lincoln, who authorized him to travel among the Union armies. Zeppelin spent a month with General Joseph Hooker’s Army of the Potomac. Accustomed to German military organization, he was unimpressed with what he saw and left to see the sights of the new continent. While visiting Minnesota, he ascended in a tethered balloon and saw the landscape laid out below him like a military topographical map. He immediately grasped the advantage of such an eye in the sky for military purposes. He was impressed.

Upon his return to Germany, Zeppelin pursued a military career, distinguishing himself in the 1870 war with France, albeit with a reputation as “a hothead.” It was this characteristic which brought his military career to an abrupt end in 1890. Chafing under what he perceived as stifling leadership by the Prussian officer corps, he wrote directly to the Kaiser to complain. This was a bad career move; the Kaiser “promoted” him into retirement. Adrift, looking for a new career, Zeppelin seized upon controlled aerial flight, particularly for its military applications. And he thought big.


Contributor Post Created with Sketch. Saturday Night Science: Countdown to a Moon Launch


“Countdown to a Moon Launch” by Jonathan H. WardIn the companion volume, Rocket Ranch, the author describes the gargantuan and extraordinarily complex infrastructure which was built at the Kennedy Space Center (KSC) in Florida to assemble, check out, and launch the Apollo missions to the Moon and the Skylab space station. The present book explores how that hardware was actually used, following the “processing flow” of the Apollo 11 launch vehicle and spacecraft from the arrival of components at KSC to the moment of launch.

As intricate as the hardware was, it wouldn’t have worked, nor would it have been possible to launch flawless mission after flawless mission on time had it not been for the management tools employed to coordinate every detail of processing. Central to this was PERT (Program Evaluation and Review Technique), a methodology developed by the U.S. Navy in the 1950s to manage the Polaris submarine and missile systems. PERT breaks down the progress of a project into milestones connected by activities into a graph of dependencies. Each activity has an estimated time to completion. A milestone might be, say, the installation of the guidance system into a launch vehicle. That milestone would depend upon the assembly of the components of the guidance system (gyroscopes, sensors, electronics, structure, etc.), each of which would depend upon their own components. Downstream, integrated test of the launch vehicle would depend upon the installation of the guidance system. Many activities proceed in parallel and only come together when a milestone has them as its mutual dependencies. For example, the processing and installation of rocket engines is completely independent of work on the guidance system until they join at a milestone where an engine steering test is performed.


Contributor Post Created with Sketch. Saturday Night Science: The Hunt for Vulcan


“The Hunt for Vulcan” by Thomas LevensonThe history of science has been marked by discoveries in which, by observing where nobody had looked before, with new and more sensitive instruments, or at different aspects of reality, new and often surprising phenomena have been detected. But some of the most profound of our discoveries about the universe we inhabit have come from things we didn’t observe, but expected to.

By the nineteenth century, one of the most solid pillars of science was Newton’s law of universal gravitation. With a single equation a schoolchild could understand, it explained why objects fall, why the Moon orbits the Earth and the Earth and other planets the Sun, the tides, and the motion of double stars. But still, one wonders: is the law of gravitation exactly as Newton described, and does it work everywhere? For example, Newton’s gravity gets weaker as the inverse square of the distance between two objects (for example, if you double the distance, the gravitational force is four times weaker [2² = 4]) but has unlimited range: every object in the universe attracts every other object, however weakly, regardless of distance. But might gravity not, say, weaken faster at great distances? If this were the case, the orbits of the outer planets would differ from the predictions of Newton’s theory. Comparing astronomical observations to calculated positions of the planets was a way to discover such phenomena.


Contributor Post Created with Sketch. Saturday Night Science: Rust


“Rust” by Jonathan WaldmanIn May of 1980 two activists, protesting the imprisonment of a Black Panther convicted of murder, climbed the Statue of Liberty in New York harbour, planning to unfurl a banner high on the statue. After spending a cold and windy night aloft, they descended and surrendered to the New York Police Department’s Emergency Service Unit. Fearful that the climbers may have damaged the fragile copper cladding of the monument, a comprehensive inspection was undertaken. What was found was shocking, and the climbers were not to blame.

The structure of the Statue of Liberty was designed by Alexandre-Gustave Eiffel, and consists of an iron frame weighing 135 tons, which supports the 80 ton copper skin. As marine architects know well, a structure using two dissimilar metals such as iron and copper runs a severe risk of galvanic corrosion, especially in an environment such as the sea air of a harbour. If the iron and copper were to come into contact, a voltage would flow across the junction, and the iron would be consumed in the process. Eiffel’s design prevented the iron and copper from touching one another by separating them with spacers made of asbestos impregnated with shellac.