Yes, There Have Been Aliens

This last Sunday a really interesting article was published in the New York Times. It is about the likelihood of the existence of alien civilizations. This study about the Drake Equation (which was the subject of one of my recent posts), updates its relevance in light of the current discoveries of a large number of exo-solar planets. If you are interested in the subject as I am, I’m sure you will find it a very interesting read.

Yes, There Have Been Aliens

Link to Article

Yes there have bee aliens

NOISE: Can’t do without it!

This is a vastly subjective subject; I would say that it is a little bit like politics, as visceral reactions can be generated by noise. One’s listening pleasure can always be someone else’s irritating nuisance, yet we could hardly do without it. We actually need noise; noise makes all kinds of things possible. And fittingly, to my earlier comparison with politics to which Aristotle described as  “the art of the possible”, I would argue that this applies also to noise.

There is a great majority of people who would agree to the extremes: a jackhammer makes horrible sounds, and a cat’s purring is very soothing. One is really loud, the other really soft, but they do share a rhythmic pattern, which makes them hard to ignore. Loudness is not a factor when we listen to a large waterfall (very loud) or a refrigerator (pretty soft). Most would agree that the fridge is the more annoying one, but these two share a linearity that makes them easier to tune out. These are the types of sounds that we are aware of, which can be defined subjectively as ‘noise’. The type of noise that I’m interested in is the type which we are least aware. This type of noise has more general applications, and is not confined to the realm of sound; it is also visual and statistical. It is the true essence of noise, and there is nothing subjective about it.

The definition of this noise is scientifically quantified and qualified, giving it different ‘flavors’ named by colors: white, pink, brown and even black. These colors correspond to the type of randomness, amplitude and graininess of the noise pattern. For example, white noise is broad and dense, widely distributed over the spectrum like white light (white noise is an idealized absolute only used for theoretical purposes, and needs infinite energy); on the other hand, brown is more granular and more random, like the jiggling of individual molecules called “Brownian Motion” from which it takes its name, and is softer to the ear. Pink sits in between brown and white; it is what we hear as “white noise”. Black noise is close to silence.

White noise and Low, Medium and High pass filters

White noise, Low, Medium and High pass filters

So what is so important about noise? Why do we need it so much? I could go through a long list but one example that is close to our musical ear is the case of vinyl. Here are some interesting applications of noise that we don’t necessarily hear consciously:

Small amounts of noise can improve hearing by helping the inner ear detect frequency signals. This is the so-called stochastic resonance effect.

The pixels in a grayscale image can be too faint to cross the threshold of visibility; adding noise energy can sometimes boost the signal above the threshold. This stochastic resonance effect or noise benefit arises in numerous physical and biological systems where a small amount of noise can nudge the system into a new state.

Noise can benefit nervous systems because small amounts of it can improve how neurons process signals- or at least it does so in almost all known models of neurons.

These facts show that noise plays an important role in our perceptions. So how is it that a noisy medium (according to all measurements made with devices such as a spectrograph) such as vinyl L.Ps. has come roaring back so that its growth has outpaced compact discs, which are in a steady decline? I see several explanations:

  • It is a nicer object than CDs, and its size allows for great graphics and cover art, and it has an irresistible retro-chic.
  • It will outlast the CD and MP3’s life by far; after all, it is made of vinyl- a close relative to oil, which has already lasted tens of millions of years.
  • The analog source of the signals (grooves etched in the plastic need no “code” to decipher); in theory, you could hear the music with your finger nails.
  • But most importantly: people like the warm sound that it produces. That last quality is the more puzzling, because wouldn’t a cleaner, clearer sound be more pleasing to the ear than a noisier one?

The conclusion, it can be argued, is stochastic resonance effect. Our ears like noise, which enhances the auditory experience; and more precisely, the noise is a conveyer that carries the waves which create the warmth that makes us feel good. The process of digital sampling by quantizing the data source needed to put music in binary form creates small steps from one sample to the next, resulting in a harsher sound, in particular CDs, which are at a 44 Kilohertz sampling rate (this quantizing effect is much less of a problem at 88 or even better, 196 khz). This resulting sound needs to be ‘smoothed over’ to reclaim the original warmth to please our ears; and what is needed to do this? You guessed it: noise. This process has a name, called ‘dithering’, and it plays a big part in digital sound processing.

LPs are a noisy medium; they generate noise and this is the nature of the medium, and it pleases our ears. So obviously, when we get the ‘original’ unbroken analog path, we notice it. The fact is, we are dwelling more and more in a digital environment, since mainly all of our information and entertainment is digitally served to us through the overwhelming influence that the internet has in our lives. We are feeling the difference when sounds are served to us through an analog medium, and whatever noise may be added back in the process is just icing on the cake.

There is a lot more to explore, and I surely will revisit this topic in the near future.

This blog post does borrow freely from the book Noise by Bratt Kosko, edited by Sarah Pillow

The Drake equation

As anyone can tell by reading my previous posts, the subject of alien civilization has been on my mind lately. So it was an interesting coincidence that I met Frank Drake recently at the University of Santa Cruz in California. He was the narrator for the Perpetual Motion show about Galileo, created by my wife’s group Galileo’s Daughters, for which I mix the visuals, using video and animation.

Frank was very nice to indulge me with my probing questions after the show. His steadfast and educated opinion about the existence of alien civilization is intriguing. Over fifty years ago (1961) Frank wrote the now famous equation that bears his name:

This equation allowed him to make an educated estimate of the number (N) of civilizations out in our galaxy, by using facts such as the number of stars in the Milkyway, the typical life of a civilization in years, and the life time of a typical star. He then adds a couple of  variables: stars with habitable planets, with a fraction of them where sentient civilization arises. Following these you can get to a number that is based in rational thinking. It became the base of the SETI research (search for extraterrestrial intelligence).

All these variables are subject to discussion and arguments, but at the time, Frank Drake estimated that a worst-to-best case scenario would be 1000 to 100,000,000 civilizations. This estimate was made in the early 1960’s, long before the current treasure trove astronomers now utilize to detect planets by using the two following methods: telescopes using the “Doppler” effect, which is the influence that planets have on their star by gravitationally pulling on them; and the even more prolific method using the Kepler space telescope, which detects  light dimming created by a planet’s obscuring the light of their star as they pass in front of it (a minuscule dip, but the sensitivity of these instruments detecting this event is phenomenal).

So, if anything, the pendulum has swung towards the larger number, and ideas about how to detect these civilizations are growing. There is one possible way that was suggested recently, which had to do with the propulsion of spacecrafts using lasers and light sails. And that idea has just become a lot more real! Read this:

The Russian philanthropist Yuri Milner, who I mentioned in an earlier post, has just pledged $100,000,000 of seed money to develop a flotilla (1000) of micro probes, propelled by laser pulses applying light pressure on the sail of each of the probes to accelerate to one-fifth of the speed of light (taking 2 minutes to accelerate from 0 to 37,000 miles per minute). This would be enough speed to reach the next closest star “Proxima Centauri” in twenty years. It is a double star and appears to have at least one planet in the habitable “Goldilocks” zone, (where water is in its liquid form).

One of the sponsors of this expedition is Freeman Dyson, the one with the concept of the Dyson Sphere. Freeman, a true original forward-thinker, had devised a few decades earlier the idea of the “Cosmic Egg“, a miniature spacecraft filled with nanobots that would hop from world to world, find what it needs to replicate itself (indeed, a little ‘cosmic egg’ factory) and then move on to the next. There is no way anything bigger than an iPhone can get to the next star in a reasonable time frame.

On the other side of that “cosmic coin”, the laser pulses (moving at the speed of light) used to propel these probes would be detectable five times sooner than the probes themselves in reaching Proxima Centauri. These pulses being emitted into the universe is a mode of transportation. It has recently been suggested that we could look for these pulses in other solar systems, as they are detectable. The fact that we are planning such a system makes it even more likely that others would be as well.

Alternatively, the same laser technology could be used to hide a civilization from being detected. If any civilization is choosing to do this, it would mean that they know something we only suspect: that there are others to hide from…

imageRonn MacFarlane, Marc Wagnon, Frank Drake, Sarah Pillow and Mary Anne Ballard

Meeting someone like Frank Drake, who has taken this eventuality to such a level is inspiring. Hopefully this civilization, ours, will live long and prosper.

 

 

Waste or not to waste (follow-up)

Csiro Parkes Observatory, Australia

Csiro Parkes Observatory, Australia

Since my last post, I came across a couple of articles that put the significance of human reaction to finding alien civilizations more into focus.
It was a ‘tongue in cheek’ comment, but this topic is probably here to stay, or should I say we’re not about to put the ‘genie’ back in the bottle. In the previous posting I was mainly thinking of the consequences of our civilization entering into contact with an alien one. But we have to consider the consequences of what just the knowledge of the discovery of an existing alien civilization would have on ours, regardless of contact. That will translate into a major re-alignment of priorities, and would affect the lives of Earthlings in unexpected and dramatic ways.
What might go through the mind of the average person when confronted with the piece of information that we are not alone – and which in turn will spread like wild fire through the info sphere? As highly social animals, no one is immune. These information nuggets have a name: “memes”, a term coined by Richard Dawkins, that describe something that spreads within a culture, from a catchy phrase to an entire belief system (like a virus). Due to our thirst for information, we are particularly vulnerable to memes, and some could be highly destructive to our civilization, potentially wrecking it as effectively as any physical weapon. One of the ways to protect us from these memes is to build another kind of sphere or cage (see Dyson Sphere from my previous blog); this one is called a Faraday Cage  which would filter information in and out. Read more about this in Nautilus Magazine.

Green Gank observatory W. Virginia, U.S.

Well, now that everyone is potentially pretty “freaked out”, here’s a nugget of information that will positively allow you to surrender to the fear of the aliens: Yuri Milner, a Russian entrepreneur, has pledged to give $100 million in the next ten years to SETI (Search for Extra Terrestrial Intelligence). This gift will allow SETI to develop new instruments, hire new astronomers/observers and allow for substantial observing time at major radio observatories (Green Bank in the U.S. and CSIRO Parkes* in Australia). And in the near future, the upcoming James Webb (successor to the Hubble) and the next-generation 30-meter telescope possess the ability to measure the atmospheric chemical composition of the nearest potential planets.
In a world divided by cultural and religious war and threatened by environmental issues, these potential “memes” and discoveries could play out in a variety of ways: they could make us reflect on the state of a world that would like to reach to the stars, but is anchored in conflict. Or it can trigger a panicked free-for-all, where every construct of our civilization is made futile and meaningless.
Either way, it will be transformational.
* This dish is the stage for a cool movie aptly named “The Dish”; it retraces the role that the CSIRO Parkes Observatory played during the flight of Apollo 11 in a smart comedy.

“Drum Talk” is out!

I am very happy to be able to announce the release of my method for music teachers and music therapists, which gives them an introduction to percussion ensembles.

It is available on iTunes for $14.99 since it is made for iBook which can be read on any Mac iPad or even iPhone. I am eager to hear from you with your thoughts and comments, I plan to update the book as necessary. Here is a short description of the book:

“Drum Talk” is a teaching method created by musician and educator Marc Wagnon, combining multi-cultural rhythms (Africa, Middle East, Brazil & Cuba) and does not require students to have any previous knowledge of music technique. This system allows the group to attain a level of complexity that would normally demand longer preparation. Its goal is to give an experience in group music making, and ranges from simple concepts to complex polyrhythms. The book of 10 lessons contains 58 video clips and 86 musical examples.

Read more about it and view some video clips at marcwagnon.com

or on the iTunes store

Drum Talk book cover

Drum Talk: An Introduction to Percussion Ensemble

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Waste or not to Waste

Provocative ideas need to be tested with the gusto to match.

Freeman Dyson is a 91 year-old physicist, and has no fear of exploring iconoclastic ideas. Many I find appealing, but some, in particular his acceptance of global warming being a good thing, is not one of them. Of course, the Sahara becoming green again could be a good thing, but is it worth the cost to other now temperate regions of the globe? For more about him read the article in the New York Times Magazine.

Dyson is also a big supporter of the analog (have you listen to an LP lately?), imagining that if his “self” was to be transferred in a different platform at the end of the universe, he would much rather be stored in an analog cloud of particles rather than in a digitized version in a networked universe. He also devised what he calls a “Cosmic Egg” which would be a nano spaceship full of minuscule nano bots, that would be able to travel fast due to their low mass, and for a long time until they found a suitable planet, and set up a nano civilization, start reproducing, build and send more eggs to explore other destinations…on and on.

The idea of his that resulted in the latest study of exploration of infra red spectrum of distant galaxies, is his vision of what became to be called a “Dyson Sphere”. There is nothing nano about this one – it goes like this: when a civilization has used all the energy available on its home planet, it would construct a sphere around its star (that would be the Sun for us), and collect all of its energy output. Even this would soon become insufficient (according to Carl Sagan), and more and more stars would be needed until most of the galaxy energy output would be collected. This activity would be easily detectable from afar since it would leak infra red emissions, while dimming the light emitted by the galaxy. It turns out that due to the laws of physics, energy use is impossible to hide.

That is what this latest effort at detecting alien civilizations has been directed towards, by analyzing the part of the infra red spectrum in which such waste energy would surface in hundreds of galaxies. We should be able to recognize the telltale signs of such a civilization. The study came up empty handed, as no out-of-balance emissions have been detected.

But this result allows us to reflect on the consequence of this failure:

“Such an expensive and greedy civilization would have no place for a more gentle and welcoming one like ours. It’s the trait of rapacious users who either have a big reason or a big insatiability”, says David Brin, an astrophysicist. Surely trying to enter in contact with such an empire would not bode well for us, as Stephen Hawkins has said. When two civilizations come into contact, it does not end well for the less technologically developed of the two.

So these kinds of ‘gas guzzling’ galactic empires probably do not exist, and this is why we do not detect them. SETI (Search for Extra Terrestrial Intelligence) is basically looking for waste energy. An advanced civilization must have found ways to reduce or even eliminate waste, so as to be invisible.

I think that this is extremely relevant to our small world problem, as it shows us the obvious path, which is to lower waste instead of increase consumption. In the past few years, what was an educated guess (the possibility of extraterrestrial life) has, thanks to the Kepler Observatory (another space telescope like the Hubble), become a more and more unavoidable outcome. Among the 3500 celestial bodies discovered by Kepler, more than a thousand (confirmed by other observatories) have been substantiated as alien planets. This allows us to extrapolate that every star in the Milky Way has more than one subject orbiting it.

In the meantime, our light emissions have obscured viewing the Milky Way for more than half of the human population. It seems to me that it will soon be the subject of myth and lore told under a canopy of artificial light. All the while we are broadcasting louder and louder…knock knock…who’s there?

To know more about this read this excellent article from Scientific American

Galaxy_alien_blog

THE OLDEST ANALOG RECORDING…by far

When the exact longitude differences between Europe and United States was to be measured, the only possible way was to put down electrical telegraph cable underwater. So far these measurements were made with chronometers, but at best with about a four second inaccuracy. So beginning in August 1857, this mission had to struggle against the north Atlantic to lay a telegraph line under water. Cable broke again and again. One ship sank, and civil war interrupted the process. Finally on December 11, 1867, the message got through, and finally at the two extremes of the continents: the island of Valencia on the western coast of Ireland and at the other end on the island of Hearth’s Content of Newfoundland, the weather, known to be mostly rain and gale, cleared just long enough on both sides to allow for a simultaneous celestial measurement. Thanks to the light speed of the electromagnetic signal through the wire, the exact distance between the two continents could be accurately measured: an analog signal, I might add.

These underwater cables had a tendency to sever themselves in the middle of the length of the ocean; somehow the assumed smoothness of the ocean floor was broken in the middle. It was found that the cable had to traverse a range of underwater mountains that rose 2000 meters above the sea bed.

The next development comes during the world wars, when the fear of U-boats resulted in the English and Americans developing Sonar technology. This technology works by continuously timing the reflection of high-frequency sound waves from the seafloor: since the speed at which the sound waves travel in water is known, the distance to the seabed or object can be calculated. (Sound waves travel faster as the density of the medium they are going through increases; I have an earlier blog musing on the subject.)

So in the 1950’s, a detailed picture of the ocean floors was emerging from sonar surveys. It was discovered that the mid-Atlantic Ridge, traversed by the first telegraph cable, was just part of a 40,000 km-long chain of underwater mountains running around the globe. When drill cores were retrieved from the ocean floor, the whole of the sea floor was found to be geologically very young. Much more so than the continents. Furthermore, the rocks were getting older as they were further away from the Mid-Atlantic ridge (as the mountains at the center became to be called).

The conclusion was that new ocean floor was being created continuously, leading in the 1960’s to the acceptance of the theory of Continental drift (so much for those that thought that the 60’s was only about sex, drugs and rock ‘n roll). This reveals the transitory nature of the kind of measurements I described at the beginning of this post – of course at a geological, not a human scale.

This finally leads me to the point of this post: it turns out that the length of these thousands of miles of new ground was recording the many switches of the Earth’s magnetic poles (the magnetic poles switch from time to time, not the geographical ones). The seafloor would, therefore, be acting like a double tape recorder, advancing in both directions from the ridge, producing strips of rock magnetized alternatively in normal and reversed direction, and symmetrically arranged about the ridge, the width of each strip would be determined by the length of the polarity interval and the rate of seafloor spreading.

There you go – the oldest analog magnetic recording on Earth, as old as the last time the East coast of the United States was joined to West Africa, a good oh, give or take 300,000 million years ago. But since it is all in motion, all this good recording will be recycled when it subsides under the continents, to make room for the new hits of the next eons.

this picture shows the successive switch of the Earth magnetic pole, as recorded on the sea floor, spreading from the ocean ridge.

This picture shows the successive switch of the Earth magnetic pole, as recorded on the sea floor, spreading from the ocean ridge.

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Facts and Fiction

I just heard this statement on NPR:

“There are more and more studies that show that giving people information does not change their mind.”

And although that is somehow not new in itself, and has been particularly obvious in the news business and the political world, it did put it quite starkly into focus. Fact-based reality is indeed a very fragile thing. The times in world history when facts did have bearing on human affairs are far and few apart, but what was achieved during these periods had a lasting influence.

Western civilization still resonates from the Greek philosophers’ insight into the physical world. Most of the stars in the sky have Arabic names, reflecting the intense interest in the calendar and orientation of the early Muslim scholars a thousand years later than the Greeks. On the other hand, these ideas reached a very small number of people.

The philosophers and mathematicians of the Renaissance looked back 1500 years to seek logic and reason from those who came before to guide their thinking process, which led to an evolving view of our world. These facts-based success stories were not widely understood by many until the 20th century, coinciding with a rise of the middle class in the western world. This was probably due in part to a more equitable education and success of the technology issued by the fact-based science behind it all. Unfortunately, the mismanagement and corruption of knowledge acquired was partly funneled into armament (the atomic bomb is a good example), and environmental abuse, which opened a wedge for doubt to fester.

Of course this is simplistic, but these drawbacks were enough for other forces to gain momentum, and utilize this breach of trust to declare full war on the factual philosophy that we still need so urgently. We cannot solve these problems by burying our heads in the sand. It is worthy to note that this development coincides with a widening of the gap between rich and poor.

There is a lot more to be said, but the main concern I have is: what can we do about it? Can we make facts sexy? Any other suggestions?

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Promoting science awareness

I Just heard a talk by Nick Sagan, Carl Sagan’s son; I am not that familiar with Carl Sagan, in the sense that I did not see the Cosmos series nor read the book. But I do know of him, obviously, and the work he did popularizing science.

But this talk made me realize a few things about him and his role. First, in this age of the Rise of Ignorance about the sciences, he is sorely missed; there is no one that really has taken his place. Secondly, he was very successful at putting his point across without dumbing it down. Lastly, his sense of wonder and enthusiasm were key in carrying the message, and it was very successfully carried across.

Of course my view is the one of a musician and the topic of this blog is the relation between science and music. And at the talk, the video clips of John Boswell were presented; he had put videos together of all these scientists: Carl Sagan, Steven Hawkins, and Richard Feyman.

He used snippets of talk and presentations and filtered them through auto tune to make them appear to sing, to some pop mix.

I do not care much about the music in these, and auto tune is to me the most annoying effect when used constantly (like any other effect for that matter). This method has become quite a phenomenon; politicians, news anchors, and so on are now the lead singers of many clips. But besides the novelty of it, the result is not very musical and the sound quality of the voice is pretty shrill. On the other hand, it is important to notice that these videos have been downloaded more than a million times. So the message is getting across and it is powerful.

Again as a composer of non-pop music, and interested in promoting critical thinking, I have a dilemma. I strongly think that music can have a role in promoting these ideas. If I want to carry this message, does it mean that I have to compromise my artistic integrity? I did try to carry some of this message with my last album, “Earth is a Cruel Master”, an instrumental collection of pieces inspired by several scientific topics. Does that make me the equivalent of a nerdy arcane formula crusher that few can understand?

I guess the right question to ask is: did Carl Sagan compromise his scientific vision in order to carry the concept to the masses? Probably not.

Another way is shown in Sarah Pillow’s live show “Perpetual Motion”. She has put it together with her group Galileo’s Daughters and science writer and author Dava Sobel that features beautiful singing (no auto tune there) along with a live video mix. Check out a video each:

John Boswell http://www.youtube.com/watch?v=XGK84Poeynk

Perpetual Motion http://www.youtube.com/watch?v=PTnJfUvlokk

Music’s origin

Imagine a long early summer sunset, and the only sounds heard are from some late crickets, and the crackling of the fire a few yards away. Venus is shining just under a young moon crescent. Other bright stars are slowly appearing, and the first to be seen is the brightest in the sky, which leads to the coldest parts. As the sky grows darker, a bright milky band shines from where the sun rises to where the moon sets.

A light breeze is blowing; you are thinking of today’s hunt, and tomorrow’s festivities celebrating the sun rising again at that point on the horizon when its path moves back to where it first came six moons ago. A big bird flies off of a nearby tree, and the coming darkness leads you into a dream.

The beauty of the still twilight inspires you to reach into the leather pouch you always keep close to your body. You take out your magic flute and start to blow into it; softly at first, recalling one of the melodies you heard at a gathering long ago near the big ice wall over in the direction of that brightest star in the sky. Then you feel the melody could sound a different way, and you go more deeply into the sounds you are producing.

women

Others gather: someone has brought a hollow piece of trunk, on which he has stretched a piece of abix skin held tightly by some wood pegs. Its pulse lays a foundation for your improvisation. Some of the people who have gathered around you start to move in unusual ways. Not walking, not running, not expressing a particular feeling– but just moving to the pulse generated by the sounds you and your acolytes are producing.

It is something new, these movements, that previously were static and meant either anger, love, hunger, or danger. But with these sounds you are producing, all of these movements become blended, in a complex meaning that is not so clear but much more nuanced. there were even some that were completely new. They must have meant something, but it was yet not clear to anyone; could it be that these movements could be combined into groups? Everyone was feeling calm, and someone even started making sounds with her mouth in a sequence, repeating the same sound over and over, synchronized with the movements and mysteriously related to your melodies….could that have meaning?

There is so much to discover and understand; somehow that evening it became just a little bit more clear. Definitely a night to remember.

This fictitious but, I think, possible scenario happened a Platonic year* and a half ago in what is now called Ulm in Germany, where Professor Nicholas Conard of Tubingen University found in one location three flutes made of bird bones.

“We report the discovery of bone and ivory flutes from the early Aurignacian period of southwestern Germany. These finds demonstrate the presence of a well-established musical tradition at the time when modern humans colonized Europe, more than 35,000 calendar years ago”.

Experimenting with the replica, he found that the ancient flute produced a range of notes comparable in many ways to modern flutes. “The tones are quite harmonic,” he said (they were pentatonic in nature: a five tone scale which skips the fourth and the seventh degrees of the diatonic scale). He adds:

“It’s becoming increasingly clear that music was a part of day-to-day life,”…. “Music was used in many kinds of social contexts: possibly religious, possibly recreational – much like how we use music today in many kinds of settings.”….”Music could have contributed to the maintenance of larger social networks, and thereby perhaps have helped facilitate the demographic and territorial expansion of modern humans…” his team wrote.

In fact, it is hard to imagine the development of musical abilities without the parallel development of spoken language. There are strong indications that language has its root in singing (I will develop on this concept in a future post).

It so happens that the Hohle Fels flute, as it is called, was uncovered in sediment a few feet away from the carved figurine of a busty, nude woman, which was also estimated to be around 35,000 years old. Now, I’ll let you make your own deductions about this synchronicity.
flute
* A Platonic Year is 24,000 solar years. It corresponds to the period it takes for the earth axis to wobble, like a spinning top in one complete turn. This phenomenon has resulted in a shift of constellations. To an observer on Earth, Vega was the north star, and the Milky Way was flowing in a different direction.