Tag Archives: Georges Melies

#AdlerWall 04: Look Up and Sketch the Moon

by Shane L. Larson

You and I live in the future. Our world is one where information is transmitted instantly to everyone, blasting out of large flat screens and small hand-held devices owned by a billion humans around the globe. Information comes in small blurts of text, a few funny pictures, and now and then in a short video. Electronic memory, captured forever in the ephemeral electronic nothingness of the internets.

It is hard to remember that there was a time, not so long ago, where moving pictures were a marvel, a wondrous example of the technological age that was just beginning to expand its blanket across our civilization. That by-gone age that introduced the world to moving pictures is usually called the “Silent Film Era” and spanned more than 3 decades, from 1894 until the late 1920s when “the talkies” began to take over. In the midst of this age of wonder, an ingenious filmmaker made his trade in France, experimenting with all manner of ways of filming and editing to take his audiences on journeys of imagination and wonder. His name was Georges Méliès, and in 1902 he released one of the great classics of film: Le Voyage dans la Lune — “A Trip to the Moon.”

(L) Georges Méliès. (R images) Scenes from "La Voyage Dans la Lune" [Images: Wikimedia Commons]

(L) Georges Méliès. (R images) Scenes from “La Voyage Dans la Lune” [Images: Wikimedia Commons]

Inspired by the novels of Jules Verne and H.G. Wells, Méliès imagined making a voyage across the cosmic gulf to visit our celestial companion. This was in the days before rockets — Méliès imagined sending a space capsule to the Moon after launching it from an enormous cannon, a perhaps not unreasonable idea given Newton’s cannonball diagram in his De mundi systemate to describe orbits!

(L) In his "De Munde Systemate" Newton imagined going into space via an enormous cannon; this was before rockets were known. (R) In 1902, rocketry still had not been developed, and Méliès imagined sending his voyaguers to the Moon by launching them in an enormous cannon.

(L) In his “De Mundi Systemate” Newton imagined going into space via an enormous cannon. (R) In 1902, rocketry still had not been developed, and Méliès imagined sending his voyaguers to the Moon by launching them in an enormous cannon.

The Moon at that time was a great mystery to us, the target of much speculation and many wild imaginings. Méliès’ vision built on that — the Moon was an alien landscape, populated by alien cultures that his explorers did not understand nor appreciate. It was perhaps an obvious target for Méliès’ imaginings. More than any other place in the solar system, the Moon is a place that we can all imagine visiting, if for no other reason than we can see it with the unaided eye.

Today, more than a century after Méliès’ voyage of imagination, the Moon is a known place. Like many worlds in the solar system, we have photographed it up close and mapped its surface in exquisite detail. But it still holds a certain mystique that other celestial destinations do not. Mostly because we can see it with the unaided eye, but more because it is the only other place in the Cosmos, besides Earth, where human beings have walked. It is a great wonder to step outside and see the distant orb of the Moon riding high in the sky, and know that people just like you once walked there. It still makes me a little breathless, and encourages me to look for the Moon every time I walk out the door. It seems unlikely that I will ever get to walk the craggy lunar landscape myself, so I fall back on the next best thing: I try to see what I can see with my own eyes.

adlerWall_sketchMoonThe #AdlerWall exhorts us to “Look up and sketch the Moon.” Most of us have seen the Moon, probably unconsciously the way we notice trees, flowers and other ordinary, everyday things. Part of the Wall’s desire for you is simply to be cognizant of noticing what you are seeing (in the same spirit of our earlier exploration in looking closely at what is under rocks). But the other part of the imperative is the sketching.

Why should we do that? Personally, I’m probably the world’s worst sketcher, but I do it anyhow. Sketching, no matter how crude and rudimentary, helps you notice things. There are many different sketching exercises that you can do, and all of them will bring the Moon a bit closer to you.  Let’s explore some of those ideas together.

Right now, picture the Moon in your mind. What does it look like? Without getting up to look at it, without pulling up a picture of it, make a crude sketch of what you see in your mind’s eye on the back of an old cell phone bill.

What did you draw? Perhaps you drew patchy patterns of light and dark. The variations in brightness across the face of the Moon are caused by the geology that shaped it. The darker areas are called maria, or lunar seas. They are basaltic lowlands, the youngest surfaces on the Moon created by vast lava flows in an earlier, active phase of the Moon’s life. The brighter areas are called terrae, the lunar highlands. These jumbled and broken landscapes are the older parts of the lunar crust, covered with craters and criss-crossed by mountain ranges, escarpments, and vast rilles.

Did you draw any craters? How about mountains? The understanding that such features are found on the surface of the Moon is almost ubiquitous. But unless you have looked at the Moon through a telescope, you probably have never seen a crater for yourself.  You cannot see any craters or mountains on the Moon with your naked eye. Until the time of Galileo, it was widely believed the surface of the Moon was smooth.

My two sketches of the Moon. (L) The Moon from memory [not very good!] (R) A direct sketch at full moon. [Images: S. Larson]

My two sketches of the Moon. (L) The Moon from memory [not very good!] (R) A direct sketch at full moon. [Images: S. Larson]

Now go out and make a sketch of the Moon, whatever phase it might be in. The patterns of light and dark are the same ones that have been seen by 40,000 generations of humans before us. The surface of the Moon is millions of years old, changing on slow geologic timescales — human lives, and indeed all of human history, are the merest flashes of an instant in the long history of the planets in the solar system. The face of the Moon you see today is the only one ever seen by humans.

Whenever we look at the sky we project all manner of human interests and problems on the sky, a manifestation of our deep and abiding desire to be part of the Cosmos. The Moon is no different than the rest of the sky in this regard. As our most prominent neighbor, it has oft been the target of imaginative musings. There is a long tradition of recognizing and naming patterns in the patchwork of light and dark — moonshadows.

The most famous of the moonshadows is the Man in the Moon, but if you look closely you can also see the Bunny in the Moon, and the Woman with the Pearl Necklace. Can you make up your own moonshadows that you can easily recognize and teach others to see?

Some of the classic moonshadows you can see in the full moon. Clockwise from upper left: the Full Moon, the Man in the Moon, the Bunny in the Moon, the Woman in the Pearl Necklace.

Some of the classic moonshadows you can see in the full moon. Clockwise from upper left: the Full Moon, the Man in the Moon, the Bunny in the Moon, the Woman in the Pearl Necklace.

The fact that you know the Moon is covered in craters and mountains and canyons is a testament to our civilization’s ability to share knowledge. But in reality, you can discover for yourself exactly what Galileo discovered, even if you don’t own an astronomical telescope. Common birding binoculars or small spotting scopes are all much better than Galileo’s first telescope, and will show you the wonders of the Moon.

You can turn your small scope or binoculars on the Moon at any time, but it is easiest to see surface features when there are strong shadows. This happens at any time during the month except near Full Moon (though you should certainly look at the Moon when it is full!). The boundary between the light and dark on the lunar surface is called the terminator — it is the dividing line between day and night on the surface of the Moon. The shadows of craters and mountains are strongest on the terminator, and if you focus your attention there, you can see some fantastic topography. If you’re inclined to carefully record the shadows you see, some simple mathematical investigations with geometry can be used to figure out how tall and wide the mountains and craters are.

Some of my sketches of the Moon. (L) The lunar terminator, made through a small birding scope. The numbers and letters are to an identification key, figured out after the observations with the aid of a detailed Moon map. (R) A telescopic sketch of the crater Archimedes. [Images: S. Larson]

Some of my sketches of the Moon. (L) The lunar terminator, made through a small birding scope. The numbers and letters are to an identification key, figured out after the observations with the aid of a detailed Moon map. (R) A telescopic sketch of the crater Archimedes. [Images: S. Larson]

If you look at Galileo’s classic sketches of the Moon, you may notice that he sketches the entire Moon. In your own viewings, especially during the crescent phases, you can often see the faint outline of the dark part of the Moon; through a telescope, you will see fleeting, ghostlike impressions of craters, lunar seas, and mountains in the ephemeral shadows. What is going on here?

This phenomenon is called “Earthshine” — sunlight hits the Earth, bounces off the Earth, and hits the dark side of the Moon, making it appear in ghostly shadows. This is the same effect that lets you see things in the shade of a tree at the park — light from the sunny parts of the park bounces off of everything and illuminates the parts of the park in shadow. The first person to explain the origin of this shadowy illumination of the Moon by Earth was Leonardo da Vinici, in his famous notebook, the Codex Leicester.

Galileo's sketches of the Moon always showed the unilluminated half of the Moon as well. You can and will notice this, with your naked eye and through a telescope, due to "Earthshine." [Image: Wikimedia Commons]

Galileo’s sketches of the Moon always showed the unilluminated half of the Moon as well. You can and will notice this, with your naked eye and through a telescope, due to “Earthshine.” [Image: Wikimedia Commons]

Even if you don’t want to sketch the craters and the mountains, even if you don’t want to peer at the Moon through a telescope or binoculars, you may still see the Moon in striking moments of beauty, framed by life here on Earth. A common experience many of us have had is witnessing a Moonrise or a Moonset against the landscape or against the skyline of the city. In many instances you get the overwhelming perception that the Moon is enormous, looking over the Earth like a gigantic cauldron of boiling light, waiting to pour itself out across the landscape.

The Moon Illusion at work over the Adler Planetarium. What my eye saw (sketch on the Left) and what my camera captured (picture on the Right) are significantly different! [Images: S. Larson]

The Moon Illusion at work over the Adler Planetarium. What my eye saw (sketch on the Left) and what my camera captured (picture on the Right) are significantly different! [Images: S. Larson]

This apparent enlarging of the Moon is an optical illusion known as the “Moon illusion.” While you can generically break the illusion by disrupting your normal viewing of the scene (try standing on your head, or looking at it upside down), the existence of the illusion does not diminish the awe-inspiring effect it has on your mind’s eye. Somewhat surprisingly, simply taking a picture often destroys the illusion — unless cropped very closely around the Moon, pictures flatten the perspective and bring peripheral parts of the scene into play, destroying whatever visual queues your brain was using to make the Moon look big. It’s weird.

The Moon is always up there, waiting for you to notice it, providing intriguing and beautiful opportunities to snap a picture or make a quick sketch. Look up! [Image: S. Larson]

The Moon is always there, waiting for you to notice it, providing intriguing and beautiful opportunities to snap a picture or make a quick sketch. Look up! [Image: S. Larson]

The Moon, like the Sun and stars, is one of the dependable denizens of the sky. Sometimes it is up during the day, sometimes it is up at night. It is constantly changing its shape, and adds majesty and brilliance as a backdrop to images of life on Earth. So the next time you’re out take a look around for the Moon; if you have a moment, snap a picture or make a quick sketch, so you can remember it.  See you out in the world — I’m the guy looking dumbstruck on the street corner, craning his head to see the Moon rising behind the city skyline! 🙂

—————————————-

This post is part of an ongoing series about the #AdlerWall. I encourage you to follow along with the activities, and post your adventures, questions and discoveries on social media using the hashtag #AdlerWall.  Links to the entire series are here at the first post of the #AdlerWall Series.

Gravity 0: Discovering Gravity

by Shane L. Larson

You and I live in the future. We are connected to each other in ways that would have stunned people who lived only a century ago. I had the good fortune growing up to know my great-grandmother, who lived to be 98 years old. My Grandma Dora was born in 1895, at a time before electricity and telephones and automobiles were commonplace. The mode of transportation when she was born was the horse and buggy, though steam had been harnessed and train lines were beginning to gird the world. The Wright Flyer would not make its first epic flight at Kitty Hawk until 1903, when Grandma Dora was 8 years old. But she lived to see humans sail the void of space, space shuttles ply the skies, and humans walk on the Moon. In just about 100 years, the span of a single human life, she saw the world change.

(L) My great-grandmother Dora [center] with her sisters Mary [left] and Arta [right] in the early 1900s. (R) Around this same time, the Wright Brothers made their historic flight at Kitty Hawk, in 1903.

(L) My great-grandmother Dora [center] with her sisters Mary [left] and Arta [right] in the early 1900s. (R) Around this same time, the Wright Brothers made their historic flight at Kitty Hawk, in 1903.

When she was just a girl, there was a young man living halfway around the world, in Bern, Switzerland. The Industrial Revolution was in full swing, and creative minds the world over were trying to imagine how to use technology and machines to change our lives, and how to patent those ideas and make money. Some of those attempts to capitalize on the rapidly evolving world wound their way through the Bern Patent Office (the Swiss Federal Institute of Intellectual Property) to the desk of Albert Einstein. For the young Einstein, a trained technical professional, the job at the patent office was just that — a job. He very much wanted to be a professor and work on science, so in the evenings he committed himself to physics the way some of us work day jobs but in the evenings work on writing novels (or blog posts about science). In 1905, those evening endeavours paid off when Einstein published four seminal papers that transformed his life, physics, and the world forever.

(L) Einstein when he was working at the Patent Office in Bern. (R) Einstein's living room, still preserved, in the first floor apartment where he worked on special relativity during his years at the Patent Office.

(L) Einstein when he was working at the Patent Office in Bern. (R) Einstein’s living room, still preserved, in the first floor apartment where he worked on special relativity during his years at the Patent Office.

Among those papers was the original paper to describe special relativity — the laws that govern physics at high speeds, approaching the speed of light. Nestled in that paper is one of the most important discoveries in physics and the one most germane to our story here:

Nothing can travel faster than the speed of light.

This was a stunning realization, because up to that point no one had ever really imagined that we couldn’t go faster than light. The speed of light had been measured famously by Danish astronomer Ole Romer in 1676 and by French physicist Hippolyte Louis Fizeau in 1849. But there had never been a reason to believe that the speed of light was the ultimate speed limit in the Cosmos.

Newton witnessed the falling of an apple when visiting his mother's farm, inspiring him to think about gravity. It almost certain is apocryphal that it hit him on the head! But art gives the story a certain reality!

Folklore is that Newton witnessed the falling of an apple when visiting his mother’s farm, inspiring him to think about gravity. It almost certain is apocryphal that it hit him on the head, but this was the beginning of the Universal Law of Gravitation, one of the most successful descriptions of Nature ever invented.

With Einstein’s realization, we began to examine the laws of physics that had been discovered up to that point, and we found a curious fact. Some of those laws, unbeknownst to us, had the secret about light hiding in them, like a pearl in an oyster.  Most notable among these were Maxwell’s Equations for Electrodynamics. Curiously, Newtonian Gravity did not have the ultimate speed limit. The classical Universal Law of Gravitation, which Newton had penned more than 200 years earlier, was built on the idea of instantaneous communication over any distance, an impossibility if there was a maximum speed of travel. Einstein recognized this and set about to resolve the issue. He would dedicate the next 10 years of his life to the endeavour. During those years, he would finally leave his job at the patent office for the life of an academic, holding professor positions at several universities around Europe. All the while, he worked steadfastly on merging gravity and special relativity.

This was not a simple matter of “imagining something new.” Newtonian gravity worked perfectly well in the solar system, where things moved slowly and gravity was weak. Einstein knew that whatever Nature was doing with gravity, it had to look like Newtonian Universal Gravity at slow speeds and in weak gravity, but not be confined by instantaneous propagation of signals. He went through a meticulous procession of thought experiments, explored new applications of mathematics (the language of science) and developed new intuitive ways of thinking about gravity. His long hours and years of brain-bending culminated in 1915 with his presentation of the Field Equations of General Relativity, now known as the Einstein Field Equations.

In 1902, Georges Méliès (L) created the film

In 1902, Georges Méliès (L) created the film “Le Voyage Dans La Lune” where an enormous cannon (C) was used to launch a space capsule carrying explorers to the Moon (R).

I think about this age of the world often, my thoughts fueled by memories of talking with my great-grandmother. What was the world like when the young Einstein was thinking about lightspeed and gravity?  It was an age of horse and buggy travel. What was the fastest people could imagine travelling in that era? In 1903 the great French director Georges Méliès told at tale of travelling to the Moon — “Le Voyage dans la Lune” — using a new technology called “moving pictures.” In that remarkable tale, he imagined a band of intrepid explorers attaining great speeds by being launched from an enormous cannon, still far slower than the speed of light.

The horse and buggy set the speed of life in those days. This is an ambulance for the Bellevue Hospital in New York in 1895, the year my grandmother was born.

The horse and buggy set the speed of life in those days. This is an ambulance for the Bellevue Hospital in New York in 1895, the year my grandmother was born.

The speed of life was slow in those days, far slower than the speed that Einstein was contemplating.  But still Einstein was able to apply his intellect to a question that perhaps seemed outrageous or unwarranted. At the time, the derivation of general relativity was mostly a curiosity, but today, a century later, it plays a central role in astrophysics, cosmology, and as it turns out, in your everyday lives!

Applications of general relativity, and the frontiers of general relativity in modern physics and astronomy. (TL) GPS system. (TR) Planetary orbits (LL) Black holes (LC) Wormholes (LR) Singularities.

Applications of general relativity, and the frontiers of general relativity in modern physics and astronomy. (TL) GPS system. (TR) Planetary orbits (LL) Black holes (LC) Wormholes (LR) Singularities.

In 2015 we are celebrating the Centennial of General Relativity. That means all your gravitational physicist friends will be all a-pitter-patter with excitement for the next 12 months, and impossible to quiet down about gravity at dinner parties.

On the off chance that you don’t have any gravitational physics friends (gasp!), for the next 13 weeks I’ll be exploring the landscape of general relativity right here at this blog. We’ll talk about how we think about gravity, the history of testing and understanding general relativity, modern observatories that are looking at the Universe with gravity instead of light, and some of the extreme predictions of general relativity — wormholes, black holes, and singularities.

My great-grandmother, Dora Larson.

My great-grandmother, Dora Larson.

My great grandmother passed away shortly after I went to graduate school, where I made gravity and general relativity my profession. In a time shorter than the span of her life, this little corner of physics had grown from the mind of a patent clerk into one of the most important aspects of modern astrophysics, at the frontiers of scientific research. Grandma Dora and I never got the chance to sit around and talk about black holes or the equivalence principle, but I often wonder what she would have thought of all the hoopla that gravity commands in modern life and modern science? What would she have seen, through eyes that saw the world grow up from horse drawn carts to space shuttles and GPS satellites?

—————————————

This post is part of an ongoing series written for the General Relativity Centennial, celebrating 100 years of gravity (1915-2015).  This is the introductory post of the series. For the first time, I’m trying short 3.5 min videos with each post to capture the essential bits of each one. Here is the YouTube Playlist with all the videos (let me know how you like them — it’s an experiment!).

Links to the successive blog posts in this series are below for reference:

Gravity 0: Discovering Gravity (28 Dec 2014)

Gravity 1: Seeing the Invisible (7 Jan 2014)

Gravity 2: The Road to General Relativity (15 Jan 2015)

Gravity 3: Curvature & the Landscape of the Cosmos (24 Jan 2015)

Gravity 4: Testing the New Gravity (7 Feb 2015)

Gravity 5: Putting Einstein in the Navigator’s Seat (12 Feb 2015)

Gravity 6: Black Holes (28 Feb 2015)

Gravity 7: Recipe for Destruction (Making Black Holes) (7 Mar 2015)

Gravity 8: Black Holes in the Cosmos (15 Mar 2015)

Gravity 9: The Evolving Universe (27 March 2015)

Gravity 10: Signatures of the Big Bang (8 April 2015)

Gravity 11: Ripples in Spacetime (24 April 2015)

Gravity 12: Listening for the Whispers of Gravity (14 May 2015)

Gravity 13: Frontiers (27 May 2015)