Category Archives: practice

non-prompted, a sandbox of sorts. use it for whatever you’d like

Total Eclipse: On the Far Side of Totality

by Shane L. Larson

How do you describe the indescribable?

I’ve been a skywatcher for more than half of the years of my life. I’ve literally spent thousands of hours with my telescope, watching the sky, making sketches to remind me of what I saw, keeping notes about appearances, and making lists of favorites to look at again. I’ve seen the rings of Saturn, and the Great Red Spot. I’ve observed supernovae, seen comets stretch across the sky, and watched the aurora borealis storm overhead. I’ve seen a transit of Venus, a once in a lifetime event.

But nothing prepared me for what I saw on Monday, standing on a hillside in Casper, Wyoming. For a brief two minutes, the Moon covered the Sun in the total solar eclipse of 21 August 2017.

Our morning started early, arriving at 5:30am. We weren’t tired now; that was later, after the eclipse was over and the adrenaline wore off! [Image by S. Larson]

My family and I, together with eight of our long time friends, set up on the grounds of Casper College, together with a vast number of our amateur astronomy colleagues who had been in Casper for the  2017 Astrocon Convention. The eclipse was due to start at 11:42am MDT, so we arrived on site early to set up: 5:30am!

By 6:00am the horizon began to glow with the scarlet tones of sunrise, and at 6:19 the Sun rose slowly over the distant horizon. We couldn’t see it, but we knew the Moon was right there too, steadfastly churning along its orbit, its shadow streaming through space, like a needle waiting to poke the Earth.

Sunrise and the appearance of the Sun. This was the moment when we knew in our cores that we were going to witness the total solar eclipse, without fail. [Images by S. Larson]

We had a row of tripods — some set up to image, some with binoculars, some with telescopes, all with solar filters. Every one of us had eclipse glasses that we constantly watched the Sun with, waiting for the first moment when the Moon would slowly begin to move between us and the Sun.

Eclipse glasses. This is pretty much how we looked all morning once the Sun came up. [Images by S. Larson]

We knew we were in for a wait, as the eclipse wasn’t due to start until 10:22am, and totality wouldn’t start until 11:42:42am!  So we paced back and forth restlessly. We took selfies with each other. We joked around. We checked the traffic, wondering if the slug of red between Denver and Cheyenne would make it to the path of totality on time. We played games. We make cookie art to track the eclipse.  You know — normal nerd herd stuff.

Just passing the time, tracking the eclipse by making art with cookies. [Images by S. Palen (L) and K. Larson (R)]

The folks down the row from us had an old Astroscan telescope, outfitted with a DIY homebuilt funnel projection screen (here are instructions from NASA) that was ideal for letting everyone see what was going on, and for taking pictures of what the Sun looked like during the partial phase of the eclipse. There was an excellent group of sunspots arcing across the middle of the Sun, and another small group down near the limb.

Our observing neighbors had an Astroscan fitted with an observing funnel (top left). The Sun had some great sunspot groups that day (top right). The screen made it easy to see the progression of the partial eclipse (lower 4 photos). [Images by S. Larson]

We also watched the progression with pinhole projections, looking at the shadows of anything with tiny holes in it. Every one showed a dazzling array of small crescent Suns, slowly being eaten by the Moon.

“Pinhole projection” is an easy way to enjoy the progress of the partial eclipse. We used a cheese grater and a Ritz cracker (Left), and also watched the dappled light in the shadows of the trees (Center and Right). [Images by S. Larson]

And then, we knew the moment was coming. We were all watching. The light got really flat and dim all around. It started getting darker, quickly. At the last moment before the Sun was completely covered, the left side burst out in a brilliant flare we call “the diamond ring.” Simultaneously, I remember the right side illuminated with a sharp edged circle, rimming the edge of the Moon. And then the Sun was gone. The total solar eclipse had begun.

We were on that hillside with maybe a thousand other people, and it erupted with cheering, screaming, whistling, and shouts of joy and astonishment. There are a million photos on the web of these precious few moments of darkness, suffused with the effervescent, gossamer glow of the Sun’s corona. They are fantastic pictures, but none of them capture everything I remember now in my mind’s eye.

The shapes are right, with two streaming horns pointing up and to the right and one down and to the left. Many of them show the bright red spot of a solar prominence peeking out from behind the limb of the Moon. A few that have been processed show the amazing interlaced structure in the corona.  My lifelong observing buddy (Mike Murray) and I agreed that the word we would have used to describe the view is translucent.

The best representation of the color I remember is the translucent blue of this plastic, in the middle of this cup (above the dark blue in the bottom). [Image by S. Larson]

But even more what I remember was it did not look white to me. It looked kind of pale blue. I’ve observed a lot of objects in the sky, and the diaphanous light of the corona reminded me all the world of the color in some planetary nebulae or bright, hot stars. I’ve been struggling to find something this same color, or a better way to describe the color. That night at dinner with my wife and daughter, I stumbled on a drinking cup whose translucent plastic comes close to being right.

But in the end, all of these attempts to describe the event fall far short of what I remember. There is nothing quite so profound as standing in the shadow of the eclipse, and it’s over before you even know it. The memory, while powerful, feels slippery — I want to cement it somehow, because it would be horrible to forget what I felt in those few moments. I immediately wrote down my notes (images of them are included at the bottom of this post), but they are pale by comparison to what is in my head. I recently met a psychologist named Kate Russo who studies and writes books about people who watch and chase solar eclipses. She names this feeling we all have about our solar eclipse experiences: ineffable.

I had resolved not to make a considerable effort to set up equipment and try to photograph the event. It was my first total solar eclipse, and I didn’t want to be distracted by the equipment and miss it. I did throw my phone up and snap a couple of pictures, but no more. It is small and grainy, but it looks like an eclipsed Sun. Knowing how fast it went, and how much more I wanted to just LOOK at it, I’m not sure I’ll ever go the route of taking pictures.

Totality. The best photo my iPhone could take? I dunno — the best photo I could take for the time I was willing to spend looking at the screen and not the eclipse! [Image by S. Larson]

In the day since the eclipse, I’ve seen many fantastic pictures of the eclipse from friends. Every single one, no matter how technically awesome it was shot, is spectacular. Why? Because they capture that ineffable moment that every person was trying to capture for their mental review later. Each one is a tiny memento, small and bright, captured on silicon and in digital pixels, that reminds the photographer what it was like to stand, just for a moment, in the shadow of the Moon.

During that same day, I’ve been looking at all those pictures, scrolling through what I had on my phone, talking with my wife and daughter, and talking with friends on social media. Always trying to cement the experience in my head. But quite by chance, I did something that I am thankful for. I set up my video camera (a little Sony Handycam) pointed at the Sun for about a half hour around totality. I didn’t know what it would capture on video, but what I wanted it for was audio.

I couldn’t have asked for any better record and memory of the event than that audio record. I’ve listened to it many times now, and each time I’m transported back to that moment on a hillside in Casper, surrounded by friends and a thousand other of my fellow humans, gazing up at the sky in stupified awe. Nothing shocks my memory with better clarity than this audio. A good friend of mine who is a psychologist in Colorado told me listening to this audio fired off mirror neurons in her brain. Mirror neurons are neural responses in your brain that respond from observing something going on as if you were there doing it yourself.

So I close this meager recounting of my experience with the audio of me and my friends, immersed in the moment. I hope you glean from it some of the joy and awe and ineffable wonder that we all felt standing there for those two minutes, and reminds you of similar moments you may have experienced and shared.

Mirabilis sole!

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I’m a fastidious note-taker. Here are images of my notes I took in the hours immediately after the event.

Notes Page 1. When big things happen, I often have my friends who are with me sign my observing log, so I remember they were there. [Image S. Larson]

Notes page 2. [Image by S. Larson]

Notes page 3. [Image by S. Larson]


Here is the previous post I wrote leading up to this solar eclipse: Total Solar Eclipse: Anticipation (20 Aug 2017)

Here is a previous post I wrote about the astronomy behind a total solar eclipse: Stand in the Shadow of the Moon (25 Aug 2014)

New Astronomy at the New Year (GW170104)

by Shane L. Larson

Newton’s portrait.

January 4 holds a special place in the hearts of scientists — it is Isaac Newton’s birthday (*). Newton stood at the crossroads that led to modern science, and astronomy in particular. He was the first person to build a workable reflecting telescope, a design that now bears his name and for the past 4 centuries has been the dominant type of telescope used by amateurs and professionals alike. Newtonian telescopes have revealed much about the Cosmos to our wondering minds. Newton was also responsible for the first formulation of a physical law that describes the working of gravity, called the Universal Law of Gravitation. Today we use the Universal Law to launch satellites, send astronauts into orbit, convert the force of your feet on the bathroom scale into your “weight“, and a thousand other applications.  There is much to celebrate every January 4.

(L) Aerial view of LIGO-Hanford Observatory [top] and in Google Maps [Bottom]. (R) Aerial view of LIGO-Livingston Observatory [top] and in Google Maps [Bottom].

But on January 4, 2017 the Cosmos celebrated with us, singing in the faint whispers of gravity itself. On January 4, the signal of two black holes catastrophically merging to form a new bigger black hole washed quietly across the shores of Earth, carried on undulating vibrations of space and time. You were very likely unaware of this cosmic event — it happened at 4:11:58.6 am in Chicago. It was a Wednesday morning, and I imagine most people were blissfully asleep. But two of the grandest pieces of experimental apparatus ever built by humans were paying attention – the twin LIGO detectors in the United States.  For only the third time in history, a gravitational wave signal from the deep Cosmos was detected here on Earth.

The signal was the signature of two black holes (a “black hole binary,” in the lingo of the astrophysicists) merging to form a new, bigger black hole. The black holes, by definition, emit no light themselves. However, astronomers know that black holes can often be surrounded by swaths of interstellar gas. The intense gravity and motion of the black holes can stir the gas into a violent froth that can emit light. At the time of the event, the LIGO team sent out alerts to astronomers around the world, who turned their telescopes skyward looking for a tell-tale signature of light bursting from the energized gas. Our best estimate of the location of the event was canvased by 30 groups, in many different kinds of light ranging from radio waves, to optical light, to gamma rays. No tell-tale emissions of light were seen. The only way we were aware of this event is from the LIGO detectors themselves.

An artist’s impression of two black holes insprialling, near merger. [Image by Aurore Simonnet, SSU E/PO]

The Gravitational Wave Signal. We call the event GW170104, named for the date it was detected. The signal from the black holes registered first in the LIGO detector outside Hanford, Washington, and 3 milliseconds later registered at the LIGO detector outside Livingston, Louisiana. All told, it only lasted about 0.3 seconds. The signal exhibited the characteristic chirp shape expected of compact binaries that spiral together and merge — a long sequences of wave peaks that slowly grow in strength and get closer and closer together as the black holes spiral together.

Comparison of the chirp waveforms from the first 3 detected gravitational wave events. LVT151012 was a very quiet event that was not strong enough for LIGO scientists to be confident it was a pair of black holes. [Image: LIGO Collaboration]

During the early inspiral phase of GW170104, where the black holes are independent and distinct, the heavier black hole of the pair was 31 times the mass of the Sun, and the smaller black hole was 19 times the mass of the Sun. Ultimately, they reached a minimum stable distance (in astrophysics lingo: the “innermost stable circular orbit“) and plunged together to form a new bigger black hole. When that plunge happened, the gravitational wave signal peaked in strength, and then rang down and faded to nothing as the black hole pulled itself into the stable shape of single, isolated black hole. For GW170104, this final black hole was 49 times the mass of the Sun.

All of this happened 3 billion lightyears away, twice as far as the most distant LIGO detection to date. Perhaps these numbers impress you (they should) — they tell the story  of events that happened billions of years ago and in a place in the Cosmos that neither you, nor I, nor our descendants will ever visit. We add them today to a very short list of astronomical knowledge: the Gravitational Wave Event Catalogue, the complete list of gravitational wave signals ever detected by human beings. There are only three.

The current Gravitational Wave Catalogue, of all known events [click to make larger].

Take a close look at the list. There are interesting similarities and interesting differences between the three events. They are all black hole binaries. They are all at least a billion light years away from Earth. Some of the black holes are heavier than 20 times the mass of the Sun, and some are lighter than 20 times the mass of the Sun. Astronomers use those comparisons to understand what the Universe does to make black holes and how often.

This is the most important thing about GW170104 — it is a small but significant expansion to this very new, and currently, very limited body of knowledge we have about the Cosmos. These three events are completely changing the way we think about black holes in the Cosmos, forcing us to rethink long held prejudices we have about their masses and origins. We shouldn’t feel bad about that — evolving our knowledge is the purpose of science. LIGO is helping us do exactly what we wanted it to do: it is helping us learn.

What do we know? There are many things we are trying to learn from the meager data contained in these three signals. The new signal from GW170104 in particular has tantalizing evidence for the spin of the black holes, and some neat assessments of how close these astrophysical black holes are to what is predicted by general relativity. But I think the most important thing about the event from the perspective of astronomy is this: the black holes are, once again, heavy. GW170104 is the second most massive stellar mass binary black hole ever observed (GW150904 was the heaviest).

The masses of known black holes. The purple entries are observed by x-ray telescopes, and represent what we knew about the size of black holes before LIGO started making detections. [Image: LIGO Collaboration]

With the first two events we had one pair of heavy black holes (GW150914), and one pair of lighter black holes (GW151226). There is a great mystery hiding there: where do the heavy black holes come from, and how many are there in the Cosmos? Perhaps they are just a fluke, a random creation of Nature that is possibly unique in the Cosmos. But the detection of GW170104 suggests that this is not the case; we’ve once again detected heavy black holes. The race is on to decide how the Cosmos makes them. The answers to those questions are encoded in the properties of the black holes themselves. How many are there? Are they spinning or not? Are they spinning the same direction as one another? How do their masses compare to one another? GW170104 is another piece of the puzzle, and future detections will help solidify what we know.

How can you help? If you’d like to help the LIGO project out, let me direct your attention to one of our Citizen Science projects: GravitySpy. Your brain is capable of doing remarkable things that are difficult to teach a computer. One of those things is recognizing patterns in images. The LIGO detectors are among the most sensitive scientific instruments ever built; they are making measurements at the limit of our capabilities, and there are all kinds of random signals that show up in one detector or the other — we call them glitches.  It is very hard to teach a computer to tell the difference between glitches and interesting astrophysical events, so we have citizens just like you look at glitches and identify them, then we use that information to train the computer. So far citizens like you have helped LIGO classify more than two million glitches, and they put more on the pile every day.

If you’d like to help out too, head over to http://gravityspy.org/ and try it out; you can do it in your web-browser, or on your phone while you’re sitting on the train to work. We have citizens from kids to retirees helping us out. If gravitational waves aren’t your thing, there are more than 50 other projects in science, arts, history and more at http://zooniverse.org/ you can try out!

A representation of the GW170104 signal, from the scientific paper. These are the kinds of images citizens can classify easily, whereas computers sometimes have trouble. [Image: LIGO Collaboration]

PS: For all of you super-nerds out there, let me point something out if you haven’t already noticed. Suppose you were to parse the name of the signal in the following way: 1701 04. Look familiar? The 4th incarnation of 1701; for the cognoscenti, this event shares the designation of the Enterprise-D. 🙂  Until next time, my friends. Live long, and prosper.

(*) When Newton was born, England had not yet switched to the new Gregorian Calendar, which we use today. They were still using the older Julian Calendar, by which Newton was born on December 25; when converted Newton’s birthday falls on January 4 on the Gregorian Calendar.

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You can read about the previous LIGO detections in my previous posts here:

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Many of my colleagues in the LIGO Virgo Collaboration have also written excellent blog posts about the GW170104 event, and the work we do to make gravitational wave astronomy a reality. You should visit their blogs!

Taking a leap (second)

by Shane L. Larson

61 seconds is all it takes
For the 9 to 5 man to be more than one minute late

outfield_playdeepSo goes the song “61 Seconds” on the 1985 debut album Play Deep, from the British rock band The Outfield.  Thirteen times since the release of Play Deep (12 Nov 1985), we humans have added “leap seconds” to our timekeeping, endeavouring as much as possible to keep our continuous record of time aligned with some Cosmic measure of time. In those moments, we had 61 seconds in the “minute.”  On the last day of 2016, we will once again add a second to our accounting of time — at 6:59:59 pm EST (that’s 23:59:59 UTC, for all you time nerds out there), a special leap second will be added. For that one moment, we will all live through 6:59:60 pm EDT (23:59:60 UTC) before the time rolls over to 7:00:00 EDT (00:00:00 UTC). An extra second of revelry on New Year’s Eve, 2016.

A statue of Abu Rayhan al-Biruni in Tehran, Iran. al-Biruni invented the modern second that forms the fundamental basis of our timekeeping. [Image by David Stanley]

A statue of Abu Rayhan al-Biruni in Tehran, Iran. al-Biruni invented the modern second that forms the fundamental basis of our timekeeping. [Image by David Stanley]

The fundamental reason for the leap second is this: all of our timekeeping is based on repeatable events. Currently, one second (according to us humans) passes for every 9,192,631,770 radiative oscillations of a cesium-133 atom.  Originally, however, the second was defined by Persian scholar al-Biruni as 1/86,400 of a solar day, where a solar day is the time it takes the Sun to return to the same meridian on the sky (typically the line from due north to due south).  Our innate sense of time, the basis for our calendars and watches and smartphones, is this one that al-Biruni used.  But here’s the rub — the solar day is not constant, because the spin of the Earth changes over time.

There are a variety of reasons for why the spin of the Earth is slowly evolving. One is the sloshing of the Earth’s oceans due to the rising and falling of the ocean tides. This is caused by the gravitational influence of the Moon on the Earth. What we observe as rising and falling tides are actually bulges of water created by the Moon. As the solid part of the Earth rotates, it turns under and through these bulges, which resist the spin of the Earth in the same way water resists you trying to push your hand through it.  The net result is some of the Earth’s spin is taken away. Other geophysical processes are at work too, including the rebound of the crust since the recession of the ice sheets from the last glacial maximum, the redistribution of water with seasons and long term climate change, crustal displacement from large earthquakes, and so on. The effects are all small, some work together to slow down the Earth, and some work to speed up the Earth. But the net result is this: the actual spin of the Earth is about 0.8 milliseconds (8 ten-thousands of a second) longer than the 86,400 second long days we define with our clocks.

So over time, the spin of the Earth falls behind our clocks, which run ahead a little more every single day. By adding a “leap second”, we are pausing, waiting for the Earth’s spin to catch up.  All things being equal, you and I may not notice. Some computers may flip out (they have in the past when we’ve added leap seconds), but largely I expect most of us will continue sipping our beverages as the Sun goes down, waiting for for 2016 to slip into the past and 2017 to arrive. The leap second will pass by, and we might not even stop to notice.

My copy of "642 Things to Write About," a writing prompt book by the community of the San Francisco Writer's Grotto.

My copy of “642 Things to Write About,” a writing prompt book by the community of the San Francisco Writers’ Grotto.

But yesterday I was thumbing through a book of mine, and it made me stop to think about that leap second a little harder. The San Francisco Writers’ Grotto has published a fantastic book of writing prompts designed to provide a bit of creative fodder for you to practice the craft of writing.  The very first prompt is this: What can happen in a second?

It’s an interesting thought to ponder. Every now and then, we have one extra second to live through (by our reckoning). What could the Universe do with that one extra second?  The answer: amazing things!  There are, of course, far too many awesome things that the Cosmos could do, but here are just a few to get you thinking…

You. Many of the cells in your body are in a constant state of growth and regeneration. To make new cells, your body creates copies of existing cells through a process called “cell division.” In order for this process to proceed, it has to replicate a copy of the genetic material in your cell, which is stored in the long strands of DNA.  All told, a human strand of DNA has about 3 billion molecular base pairs — the building blocks of the DNA ladder. If you could stretch a strand out straight, every strand of DNA would be about 2 meters long. The doesn’t sound very long, until you remember that it is all squished inside a cell, which is too small for your eye to see!  So suppose your cell is duplicating this DNA strand — molecular machines crawl along the DNA strand, reading it out and making a copy. How many base pairs can it read in 1 second?  About 50.  If you do some quick math, 3 billion base pairs divided by 50 pairs per second means it should take about 694 days for your body to replicate a single strand of DNA!  It doesn’t take this long though, because the replication process involves an entire workforce working on reading out different parts of the DNA in tandem; all told, it takes about one hour to complete the replication process — so in 1 second, the teamwork of all the molecular machines working the strand copies about 830,000 base pairs EVERY SECOND.  Is that a lot?  If each base pair were like a letter in your genetic alphabet, 830,000 letters is roughly the number of letters in a 600 page novel.

The Sun, imaged by NASA's Solar Dynamics Observatory (SDO).

The Sun, imaged by NASA’s Solar Dynamics Observatory (SDO).

• The Sun is ultimately the source for most of the energy on Earth. It’s energy is released from nuclear fusion deep in its core, where it burns 600 million TONS of hydrogen into helium every second, releasing energy that eventually makes its way to the surface, making the Sun luminous. At that rate, it will burn a mass of hydrogen equal to the mass of the entire Earth in 70,000 years.

• Suppose you use your leap second to shine a laser beam at the Moon. The beam travels at the speed of light, the ultimate speed limit in the Cosmos. It will almost reach the Moon by the time the leap second is over, but will fall just short by about 56,000 miles. It took Apollo astronauts about 4 days to cross the empty gulf between the Earth and the Moon.

• Every second of every day, 4 or 5 babies are born on Earth. About 2 people die at the same time. The population of our small world is growing, even during our extra leap second.

Unfortunately, many of us spend too many of our seconds in traffic. :-(

Unfortunately, many of us spend too many of our seconds in traffic. 😦

• If you are cruising down the freeway, heading to a New Year’s Eve celebration with your partner or friends, and are travelling at 70 miles per hour (112.6 kilometers per hour), then in a single second you travel 31.3 meters (102 feet and 8 inches). That extra second on the clock gains you an extra hundred feet in your journey.

• You are almost certainly reading this post right now on a mobile device or computer, connected to the vast electronic storehouse of human knowledge called “the Internet.” It is hard to quantify the amount of information on the internet, or what is going on globally at any instant in any kind of meaningful snapshot, but there are Internet Live Stats to give you a sense of the tremendous amount of activity that is jetting electronically around the world. In one second, almost 41,000 GB of data are transferred. That sounds like a lot of information, and it is. Neurologists estimate your brain’s memory capacity to be about one to two million gigabytes — 1 second of time on the internet is roughly 4% of your total brain capacity.

• Like the Moon orbits the Earth, the Earth orbits the Sun, and the Sun orbits the center of the Milky Way. On its journey around the Sun, the Earth is travelling at roughly 108,000 kilometers per hour. In one second, we all travel 30 kilometers farther around the Sun. By contrast, the Sun itself is travelling at about 828,000 kilometers per hour, completing its orbit of the galaxy every quarter billion years. In just one second, you complete 230 kilometers of that journey. When the clocks stall for our leap second on New Year’s Eve, we’ll make it that much farther around our galactic circuit.

There are few objects that personify the modern dependence on electricity as well as a light bulb. The cost for and numerical value for the amount of energy they expend makes them seem somehow diminutive, but recasting that energy in terms of a physical effect on you makes it more tangible.

There are few objects that personify the modern dependence on electricity as well as a light bulb. The cost for and numerical value for the amount of energy they expend makes them seem somehow diminutive, but recasting that energy in terms of a physical effect on you makes it more tangible.

• In one second, every 100 Watt light bulb left on in your house, whether you are using it or not, uses 100 Joules of energy. At current electrical energy rates in the United States (about 12 cents per kilowatt hour), that’s less than 1/1000th of a penny, so it doesn’t seem like a lot of energy. Is it?  This is about the same amount of energy as a 9-inch cast iron skillet dropped on your head from a height of 33 feet (don’t look up — it’s going to hurt real bad when it hits you, because this is a LOT of energy…). Coincidentally, this is roughly the same amount of energy expended by your metabolism to keep you alive, every second of every day — you are the energy equivalent of a 100 Watt lightbulb.

Me and Xeno, burning our extra leap second together taking selfies for the blog!

Me and Xeno, burning our extra leap second together taking selfies for the blog!

• A resting human heart will beat just more than once per second (somewhat less than that, if you’re in great athletic shape). By contrast your cat has a heart rate roughly twice that of a human; in the extra leap second, your cat’s heart will beat twice. Dog heart rates vary by size; smaller dogs have rates like cats, bigger dogs have rates like humans. But everyone will get some extra beats in during the leap second.

Speedcubing is a competitive sport to solve Rubik’s Cube type puzzles in as short a time as possible. To date, there are only 3 successful solves of a classic 3x3x3 cube in less than 5 seconds by a human: Lucas Etter (4.90 sec in 2015), Mats Valk (4.74 sec in 2016) and Feliks Zemdegs (4.73 sec in 2016). Etter and Valk each solved the cube in about 40 turns — just over 8 face turns every second. Zemdegs made 43 turns, a blistering 9 turns per second to capture the world record. Speedcubing is a sport where a leap second is almost an eternity…  The current world record held by a robot is just 0.887 seconds — the machines don’t even need a full leap second to solve a Rubik’s Cube…

Just a few of my cube-style puzzles. The cube in the front right side is a cube designed for speedcubing. I am definitely NOT a speedcuber!

Just a few of my cube-style puzzles. The cube in the front right side is a cube designed for speedcubing. I am definitely NOT a speedcuber!

The list could, of course, go on. You may find it entertaining to think about things that interest you, or ponder things you notice in your life. Ask yourself: what could that extra second be useful for? But after you’ve enjoyed the leap second, sit back in your party hat and puff on your kazoo, and think about the following: time is a real thing. It is clear from the goings on of the Universe around us that time is marching steadily onward; physicists call the evidence of this inexorable stream of time the “Arrows of Time.” But the accounting of time — the division of units of time into units called seconds, and the enumeration of those seconds as they count our way steadily toward tomorrow, are a purely human invention. The Cosmos does not care that there is an extra “leap second” in 2016, not any more than it cares that there is a year called 2016 on some backward blue planet in some forgotten corner of a single small galaxy amidst the 500 billion galaxies that fill the Universe.

The invention of timekeeping, and the invention of the year, and the hour, and the minute, and the second — those are human constructs made with a single purpose in mind: to help us understand the Cosmos around us. These constructs of time are the manifestation of our ability to reason things out, a representation of our ability to consider ideas both complex and abstract and describe and represent them in so simple and understandable of a way that every child, woman and man on the planet can carry a device to tell them how the seconds are passing us by. Which makes me think: it takes about 1 second for me to glance at my watch or smartphone and process what I see. I can waste my extra leap second this  year checking the time… 🙂

Happy New Year, everyone. Enjoy your leap second; I’ll see you back here in 2017.

#AdlerWall 05: Share Interesting Observations, Ask Questions

by Shane L. Larson

Apparently this creature eats quarters.

Apparently this creature eats quarters.

My wife and I just bought a new couch and when we flipped the old one over to carry it downstairs, a quarter fell out. When I was in high school, arcades were the rage and a quarter was a ticket to a nice half-hour playing Xenophobe or Blasteroids. These days, it goes in my pocket and gets spent on parking. Despite the sad evolution of my life into adulthood, the appearance of the quarter sparked an interesting thought: I don’t remember dropping a quarter in my couch, and probably no one else would either, so that must mean almost everyone’s couch likely has a loose quarter in it! That observation, sparked an interesting question: how much money in quarters is hidden in couches?

(L) How I used to spend quarters. (R) How I spend quarters now. If the place on the left still existed, I could feed the the thing on the right with my phone and put those quarters to good use! :-)

(L) How I used to spend quarters. (R) How I spend quarters now. If the place on the left still existed, I could feed the the thing on the right with my phone and put those quarters to good use! 🙂

Because you and I live in the future, information is at our fingertips. I pulled my phone out of my pocket and was quickly at the US Census site, which told me there are approximately 116,000,000 households in the United States (this page is where I landed). So if they all have a couch, and each couch has a quarter in it, that amounts to:

$0.25 * 116,000,000 = $29,000,000

There are 29 MILLION dollars in quarters hiding in couches! This observation has sparked some interesting discussions with friends that are wide ranging and varied: is there really only 1 quarter per couch? How much money disappears from circulation every year? Is there some way we could collect all that money? What could we do with $29 million?

This little exercise is something known as a “Fermi Problem,” — taking something you know (my couch has a quarter in it) and figuring out the implications based on other things you know (the number of households in the United States). Scientists use the method all the time to understand what the Universe is all about, particularly in astronomy where we don’t know much. But the interesting bit about the quarter question is not the number, it is the discussions that ensue afterward.

Just a few observations I have made and shared with friends, found on my smartphone. You most likely have a similar set!

Just a few observations I have made and shared with friends, found on my smartphone. You most likely have a similar set!

You make observations of the world around you all the time, and share those observations on social media or over coffee with friends. I know you do, because I see jillions of people everyday taking pictures of flower bushes and posting them to social media, asking friends over coffee if they noticed they way the clouds were streaked over the city that day, speculating on why the traffic was heavy or light today, or simply enjoying the spectacle of the brilliant turquoise color of the lake on a sunny day. You see the world around you and record it and talk about it, every single day.

adlerwall_questionsobservations

Given our social connectedness in modern life, this week’s exhortations from the #AdlerWall are ones that might not seem totally incongruous: “Share Interesting Observations” and “Ask Questions.” We are all good at this to some varying degree, but kids are masters. Children ask incessant questions of their parents:

“How do airplanes fly?”

“Where do frogs go in the winter?”

“Why do we say ‘bark’ to mean the sound dogs make and the skin of a tree?” 

They also share interesting observations:

“Look how you can make a loud sound by squishing your hand in your armpit!”

“If I hit my spoon right here, it flips oatmeal WAY over there!”

“The shadows from this tree look like an octopus!”

But sadly, somewhere along the pathway to adulthood, many of us lose that unbridled enthusiasm we had as children for exploring the world around us, and declaring our discoveries to the world. Sure, I’ve wondered how many gummy bears I can fit in my mouth and figured out the answer (37) — who hasn’t? It’s not that we don’t know how to ask questions and share our observations.  It has just become the societal norm to squelch the unbridled enthusiasm.

Yes, that’s right: squelch, not kill. Because in the quiet moments, we all give into the most basic impulse to ask a question, to look at the world around us and see what is going on. You might not always post a picture of the weather radar during a torrential thunderstorm, but you still made a screen capture. You have stayed up too late at night because you went to Wikipedia to find out about The Great Platte River Archway and two hours later found yourself still on your tablet, having randomly navigated through clicks until you were reading about the Toledo War. You’ve almost certainly been hanging out with your friends, when someone has asked some esoteric question about the difference between fountain pens and calligraphy pens, igniting a debate that was only resolved by asking Google or Wikipedia.

img_7696For most of us, making interesting observations and asking questions of our friends and the internet are diversions to everyday life, something we do for the sheer enjoyment of learning. But lurking just below the surface of those questions and observations is always a myriad of important ideas and applications, some of which we understand and some of which we may not. Irrespective, it points a simple and inescapable fact: we are all close to being scientists, simply by doing what we do — asking questions and making observations.

Let me illustrate with a curious observation I just made the other day. I have a vertical glass shower door; the glass is maybe 10 mm thick. If you put your eye right up against the edge of the door, and look into the glass (not through the glass), you a mesmerizing collection of reflections inside the glass door!

The view inside a glass door, looking edge on into the glass.

The view inside a glass door, looking edge on into the glass.

I’m sure I could work out the physics of the all the reflections as to why it happens (and could probably subject some future students to the analysis of that problem), but instead I’ll just share that observation with you. The next time you walk through a glass door, take a moment and peer in through the edge, looking longways into the glass — you’ll be treated to the same awesome spectacle I discovered. Maybe you’ll show it to a friend, or you’ll sketch it in your pocket notebook, or you’ll create a new glass sculpture inspired by the sight.  Irrespective, I’ve shared my observation with you, and hopefully shown you something you haven’t see before!  You should share what you see too.

So what does that have to do with anything? Peering into the glass of your shower door produces a spectacle that is fun and pleasing to behold, like a piece of symmetric art or a kaleidoscope. But the basic physics, called internal reflection, led to many, many modern applications, not the least of which are fiber optics, and the heart of most high-speed communications networks that are likely streaming internet and movies into your home right now. Binoculars have a pair of prisms that use internal reflection to gather the images of distant objects and route them through the binoculars to make a correct, right-side up image at your eye. Internal reflection of light in a raindrop takes the light from the Sun behind you, and directs it back at you to make a rainbow. And perhaps last, but not least, internal reflection is the basic physical principle behind infinity mirrors (IMHO, one of the coolest pieces of home decor you can have — your spouse may or may not disagree…).

Everyday examples of internal reflection. (Top L) Binoculars. (Top R) Rainbow creation by raindrops. (Bottom) Light propagating through a fiber. [All images from Wikimedia Commons]

Everyday examples of internal reflection. (Top L) Binoculars. (Top R) Rainbow creation by raindrops. (Bottom) Light propagating through a fiber. [All images from Wikimedia Commons]

All of this is connected, in a simple way, to the little pane of glass on my shower door. The world is a strange and wondrous place, full of moments of giddy discovery if you take the time to notice. 🙂

So I’ll see you out in the world — I’m the guy blocking the entrance to the coffee shop as I try to snap a picture looking longways into their glass door. 🙂

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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.

Why you SHOULD respond to student requests

by Shane L. Larson

To my colleagues in professional science:

There has been a tremendous and acerbic backlash over the last week against a current popular practice of K-12 students emailing professional scientists with a list of questions they would like the scientists to comment on. I too have received these emails, and I have to very clearly state (in case you haven’t already been in one of these debates with me) that I have an unpopular view on this issue: I vehemently reject the view that we cannot respond to these emails. It is part of our professional obligation to society to respond to these notes.

In the spirit of intellectual debate, which is the purported hallmark of our discipline, let me recount some of the many aspects of the arguments that have been swirling around.

The Scenario. Emails will sail into our inboxes from (usually) middle-school science students, that asks the scientist if they could answer a series of questions.  Here is a typical one that made its way into my inbox.

examples

These emails are often clearly part of a classroom activity assigned by a teacher. There are those of us who diligently respond to as many of these as we can; we share them among our colleagues when we can’t get to them ourselves. But many of my colleagues simply don’t see the point in engaging scientists this way; they feel like they cannot or do not have the ability to respond to these requests.  Which is where the debate begins to swirl.

(*) They can just look this up on Wikipedia!  Perhaps. But even a casual inspection of science pages on Wikipedia will reveal that it has become an increasingly difficult resource to use, particularly for non-scientists. Wikipedians have taken the viewpoint that entries on the site should contain all the information one could traditionally find in a book. Many entries, especially those related to science, have wide ranging and rambling connections from all branches of science and more often than not divert into mathematical rambling. One earnest sixth grader asked me “Can you explain what a black hole is?” I would say the Wikipedia page on black holes is decidedly NOT for a sixth grader!

(*) These are thoughtless stream of consciousness questions about topics that they just picked out of a hat. They didn’t put any thought into these.  Perhaps in some cases that is true. But it is understandable — we’re talking about middle-schoolers.  For example, almost everyone has heard of black holes, but very few know enough to ask better questions than “what are they really?” But a carefully constructed answer from you can (and will) spark deeper interest, and can (and will) provide a better foundation for the next time they have a chance to ask a scientist a question — perhaps in class, perhaps in a public lecture, perhaps as part of an organized interface activity (like Adopt A Physicist).

(*) They should learn to read and process information from online and print sources; it’s a necessary skill.  That’s right, it is and they should. But they are perhaps 12 years old, and you are saying that from the far end of a PhD in modern science. Learning to read and process information, and more importantly learning how to find reliable sources of information, is something I spend time teaching my undergraduates and my graduate students. It is not as easy as you make it sound when you speak from behind your PhD. I’m sure if you talked to their teachers, you would find that they are doing activities to practice learning the skill you so ardently insist they must learn. But when you are a K-12 student, it is hard to exercise whatever mastery you have of that skill to glean something important about the modern frontiers of science.

(*) I don’t have time to respond to all the requests I get.  Does responding to a lot of emails from students and random members of the public take time? Of course it does. Just like answering your own students. Just like answering your collaborators. Just like answering your department chair or dean. Just like doing research. Just like writing grant proposals. We all have tremendous pressure on our time; that is a fact of life and simply the state that modern science finds itself in. And the truth is that we all spend time on what we value and prioritize; if you don’t value something, then you don’t do it or you don’t spend time on it. If you do value something, you make room for it and devalue something else — it all boils down to priorities and the calculus of not being able to do everything. If you aren’t doing something because it takes too much of your time to do it, you have to be willing to say, “this isn’t important enough for me to spend my time doing. I have other things that I think are more important.”

I get a handful of these requests, but not so many that I can’t answer them; far fewer than I get from my own students, to be perfectly honest. If I do get too many, I share them among colleagues. Given that our lives as scientists are dedicated to solving the hardest problems known to our species, I find it hard to believe that someone inundated by an unanswerably large number of these requests cannot figure out a way to get responses to these students.

(*) I don’t see the pedagogical value of having students email a scientist. Students shouldn’t have answers hand fed to them.  It is NOT for you to decide what is pedagogically useful, it is for the teacher who made the assignment. They have their own learning goals and their own objectives for everything they assign their students, just like you do in your own classroom. It is NOT for you to judge what they do in their classroom any more than it is for me to judge what you do in your classroom.

You should take one of the sets of questions you get, and try to find the answers on your own. Try not to view webpages and books through the lens of your professional degrees; if you find that hard, ask your own kids or a neighbors kids to evaluate a resource you think is useful.  I think you will be surprised — while there is much good science out there for people to find, there is a lot of not so good explanations as well. The signal to noise ratio is very low; you and I have been explicitly trained to work through that.

But the most important reason for me to respond to a student inquiry is they will get something different in a response from me and you than they can get from any book. Perspective, experience, personal reflection — the human side of science, the personal side of science, an illustration of what I think is important as a scientist, the history and heroes that I think are important that aren’t always described in books.

When I answered the questions above, what did I add that couldn’t be had elsewhere?

How long does it take to produce a star? Sure, you can look up the collapse time for a molecular cloud to stars, but I also talked about the scope of the question, pointing out that one could have also thought about the previous generations of stars that made the material that is needed to create a star system like ours.

Do stars have color? I made sure in my answer that the student heard the names Annie Jump Cannon and Cecilia Payne-Gaposchkin.

Do I believe in life elsewhere? An opportunity to talk about a personal belief, and where that interfaces with research science on the topic — a chance to illustrate the all too human part of science. I also pointed at one of the finest explorations of the question I have ever seen — Peter Mulvey’s song, “Vlad, the Astrophysicist” (YouTube video here); the intersection of science and society at its finest.

In the end, I think it boils down to this: we like to make loud noises about the current state of public understanding of science, but tucking our heads down is part of the reason the world is in the state it is in. It may have been okay 40 years ago to keep your attention narrowly focused on research; but 40 years ago the Cold War and the military-industrial complex allowed science to enjoy unprecedented support in the form of funding and societal tolerance.  That is not the world today; science is regularly challenged and questioned, in society and in the halls of government, much to the detriment of our civilization and the future of our planet.

But all is not lost. There is tremendous interest on the part of students and the public about science, in large part because of the very prominent and inspiring successes of our experiments that society has invested in: LIGO, the LHC, the Hubble Space Telescope, and many, many others. A few of our august bunch are very prominent in the public eye: Brian Cox, Lisa Randall, Neil deGrasse Tyson. Before them there was Rachel Carson, Carl Sagan, and (still!) David Attenborough. They have set a fire in the minds of your neighbors and in the minds of every science teacher on the planet who are now trying to light that same fire in the minds of their students. They will do their best to light an ember, but only you and I can fan the flames. There is something unique and special about communicating directly with someone who has seen the Cosmos through the eyes of the Hale Telescope, or someone who has stood over the arm of LIGO, or watched a vista of Mars slowly unfold as Curiosity sends us a picture from over the next rise.

Out of an entire class of 7th graders, will you move and inspire all of them to a life of science? Of course not, and you don’t need to. But many of them will remember later in life that they once talked to a scientist who took time out of their schedule to respond to them.  And a few will be inspired.

In one of the many dilapidated boxes that my mother has carefully preserved is a bundle of letters I received in my childhood. One is a letter I received in 7th grade from an astronomer (physicist?) at the University of British Columbia, who took time to write a paper letter in response to an earnest inquiry from a young boy who wanted to know what it took to become an astronomer. I have another letter (undoubtedly a form letter?) from someone at NASA in 1986, assuring a worried and spiritually crushed young boy that NASA would, eventually, return to space in the wake of the Challenger disaster. These are paper responses, with stamps and envelopes and everything; not even as easy as an email.

These were scientists who made the time in their busy schedules to respond to a inquiry from a student, and in the end I think it made all the difference in the world.

#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! 🙂

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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.

#AdlerWall 03: Look for Patterns

by Shane L. Larson

(L) John Trusler (R) William Blake

(L) John Trusler (R) William Blake

In August of 1799, the Reverend John Trusler commissioned a pair of watercolors to illustrate the concept of “malevolence.” As a philosophical construct, we often regard concepts such as malevolence as being aspects of human behaviour that are part of our free will, not as natural phenomena that are able to exist independent of our free thinking. Does malevolence exist outside of humans, in Nature itself? Philosophers may differ, and certainly artists’ interpretations may vary widely. Perhaps not surprisingly, Trusler was not happy with the first painting he received.

Blake's painting of "Malevolence." [From the collection of the Philadelphia Museum of Art]

Blake’s painting of “Malevolence.” [From the collection of the Philadelphia Museum of Art]

The painter commissioned by Tusler was none other than the great English artist, William Blake.  The two shared a contentious exchange in a pair of letters that month about Blake’s depiction. In a letter on August 23, Blake admonished Tusler that we all see the world differently, writing:

The tree which moves some to tears of joy is in the eyes of others only a green thing that stands in the way. Some see Nature all ridicule and deformity…and some scarce see Nature at all. But to the eyes of a man of Imagination, Nature is Imagination itself.

Blake’s exhortations to Trusler dance around an interesting and lovely conundrum — what is Nature and how do we separate what Nature is from what we perceieve or think of it?

Consider clouds. In your high school science class, you may have once been told that clouds are suspensions in the Earth’s atmosphere, huge agglomerations of tiny water droplets and ice crystals. Most of the familiar clouds form in the troposphere, the lowest part of the Earth’s atmosphere where weather happens. Gossamer and diaphanous, they are pushed around by the winds of the world, carrying weather and moisture to the far flung corners of our planet. Meteorologists, partnered with amateur cloud watchers, have categorized a large number of cloud types, though if you restrict your attention to the most common there are only ten or so that you encounter most often (see NOAA’s “Ten Basic Cloud Types”).

The most common types of clouds, only a few of the more than 60 types classified. [Image: Wikimedia Commons]

The most common types of clouds, only a few of the more than 60 types classified. [Image: Wikimedia Commons]

But many of us have, at some point in our lives, wasted away an afternoon staring at clouds in the sky. Part of those lazy gazings is calling out shapes and figures we see in the clouds — bunnies, turtles, ships, books, hands.

There are clearly patterns in the clouds. Nature made the clouds, so Nature made the patterns. After many long years of staring at the sky, we have elucidated some regular, recurring shapes and forms that Nature creates over and over again, and we’ve given them names: cumulonimbus, altostratus, cirrus, and so on. By a similar token, the shapes and figures we recognize as bunnies and sailing ships are also patterns we have elucidated from staring at the sky. What’s the difference between our observations and Nature’s patterns? What’s the difference between afternoon figures and the cloud archetypes?

Some clouds seen from airplanes. What do you see? On the left I see a trilobite, a kid blowing a bubble, and cauliflower. On the right I see a poodle, and a shaking fist.

Some clouds seen from airplanes. What do you see? On the left I see a trilobite, a kid blowing a bubble, and cauliflower. On the right I see a poodle, and a shaking fist.

One of the great realizations we have made about the world is that it is predictable. The world does not evolve randomly, changing each day in unpredictable and unexpected ways. Quite the contrary — when I throw a water balloon up in the air (or, possibly, at someone) it always comes back to the ground. The Moon moves through a steady progression of phases every 29 days, always in the same order, just as it has for all of recorded history. A popsicle always melts when left on the kitchen counter. All of these happenings, and the many others that surround us in the natural world, occur according to precise sets of rules that we call the Laws of Nature. The fact that we can recognize patterns, that we can deduce and use the Laws of Nature to improve our lives, provides the impetus for one of the great endeavours of our species — science.

When we look at the clouds, there are two sets of patterns in play. One set of patterns are the recognizable shapes and forms of the basic cloud types. Each of these different forms is governed by a particular realization of the Laws of Nature. They are predicable and repeatable, appearing anytime the same physical conditions appear in the atmosphere. Consider “Kelvin-Helmholtz clouds.” They can form when layers of wind are sliding across one another, with the upper layer moving faster than the lower layer, creating turbulence at the boundary between them.

A classic example of Kelvin-Helmholtz clouds, created when different layers of wind slide across one another. [Image: Wikimedia commons]

A classic example of Kelvin-Helmholtz clouds, created when different layers of wind slide across one another. [Image: Wikimedia commons]

By contrast, the picture patterns that you can pick out staring up at the sky are unique to your own experiences and interpretations. You can certainly point them out to friends and get them to see what you see. But left to your own devices, you may see a turtle whereas your dearest friend may see a hoagie sandwich.  These are patterns made by your mind; the difference between them and the patterns made by Nature is that the patterns of the natural world are predictable and subject to rules. Our job as scientists and observers of the world is to figure out what those rules are.

wall_patternsThe #AdlerWall this week exhorts us to “Look for patterns,” and that “patterns can be man-made or found in Nature.”

So what kinds of patterns can you find around you? There are clearly patterns that humans make, usually quite deliberately. Our brains crave the regularity and dependability of patterns. One of the most obvious places we encounter patterns is in woven textiles. There are global patterns — stripes, dots, space cats — that you can see standing next to your friend with the loud and colorful shirt. But there are smaller, more subtle patterns you can see if you look closely, notably the interwoven fibers that cross up and over one another to give the fabric its structure. The interlocking up and down, over and under pattern of individual fibers is a human invention, though who thought of it and when is now lost to history; the oldest known woven textile fibers date to about 6000 BCE.

There are many patterns to be seen in textiles, all of them made by humans. The patterns your eye can see, as well as the underlying patterns in the weave of fabric. Patterns occur on all levels. [Images: S. Larson]

There are many patterns to be seen in textiles, all of them made by humans. The patterns your eye can see, as well as the underlying patterns in the weave of fabric. Patterns occur on all levels. [Images: S. Larson]

Carpets are another great place to see human-created patterns. These grace the floors in the Salt Palace Convention Center in Salt Lake City. I want to know whose job it is to make up these patterns!

Carpets are another great place to see human-created patterns. These grace the floors in the Salt Palace Convention Center in Salt Lake City. I want to know whose job it is to make up these patterns!

In a similar way, there are impressive patterns visible in Nature too. On cold winter days, frost ferns can form on your windows. These beautiful displays of symmetry look almost organic in nature, but result from water molecules binding to other water molecules. As a large structure forms, the molecules are forced to remain near the cold surface of the glass, and the structure of the fern emerges. Frost ferns exhbit fractal structure — a repeating pattern that appears on many many different size scales. We see fractal structure in tree branches and clouds as well.

A classic frost fern that formed on my sliding glass door this spring. [Image: S. Larson]

A classic frost fern that formed on my sliding glass door this spring. [Image: S. Larson]

There are other patterns in Nature that you can notice. I just popped outside, and with a few quick sweeps found this rock on the gravel path next to my house. I could have picked up any old rock and found something interesting, but this one has a clear structural pattern. Look closely at the exposed, broken surface. It is comprised of a myriad of interlocking small crystal structures. I’m not a robust rockhound (I just pick up cool rocks and carry them around in my pockets), but this looks like a quartzite of some kind. Quartzite is a metamorphic rock — a rock that has formed by transformation under extreme heat. In the case of quartzite, extreme pressure and heat on sandstone variety rocks causes the glassy minerals in the sand to break down and reform in crystalline arrays, not unlike the one you see on the surface of this rock.

An everyday rock, picked up off a gravel path, shows a jumble of quartz crystals on its surface. [Image: S. Larson]

An everyday rock, picked up off a gravel path, shows a jumble of quartz crystals on its surface. [Image: S. Larson]

You can see much more robust crystal formation in a kind of rock known as a geode. Geodes are roughly spherical rocks with a hollow core, where crystals have slowly grown inside the core. Beautiful (and expensive!) specimens can be bought, but breaking open common geodes will reveal a beautiful little garden of crystals. Crystals are a special pattern of matter that arises from molecules that have regular geometric shapes that are preserved when the molecules are stacked together. The regular geometric shape of the crystal that you can see with your eye is a clue to the microscopic alignment pattern of the molecules that your eye cannot see.  Salt crystals and sugar crystals are other examples.

Geodes are known for their crystal structures. The crystals are macroscopic manifestations of the underlying molecular shapes -- large patterns building from small patterns. [Image: S. Larson]

Geodes are known for their crystal structures. The crystals are macroscopic manifestations of the underlying molecular shapes — large patterns building from small patterns. [Image: S. Larson]

Another example of patterns, where human and Nature’s patterns collide is in the layout of city streets. I grew up in the American west, on the fringes of the Great Plains of North America. There the landscape is vast and flat, and humans could have laid their streets out willy-niIly in any way they wanted.  But a quick glance on satellite shows the roads are usually in a nearly perfect grid, roads running straight north-south or straight east-west. This is not true everywhere. In central Pennsylvania, the rolling landscape of the Appalachian Mountains strikes across the state from the southwest to the northeast. If you look at a town along the rolling, folded ridges you see that the roads and streets are aligned parallel to the mountains — humans patterns have been influenced and shaped by the natural patterns of the world around them.

Human patterns [streets] often follow Nature's patterns [terrain]. (L) Fort Morgan, Colorado is in the Great Plains and streets run N-S and E-W, oriented to the cardinal directions defined by the spin of the Earth. (C) In central Pennsylvania the Appalachians form long ridgelines and valleys. (R) Cities like State College, PA have street grids aligned parallel to the terrain of the mountains in the area. [Images: Google Maps]

Human patterns [streets] often follow Nature’s patterns [terrain]. (L) Fort Morgan, Colorado is in the Great Plains and streets run N-S and E-W, oriented to the cardinal directions defined by the spin of the Earth. (C) In central Pennsylvania the Appalachians form long ridgelines and valleys. (R) Cities like State College, PA have street grids aligned parallel to the terrain of the mountains in the area. Click to enlarge. [Images: Google Maps]

But seeking patterns in everything is a dangerous proposition — while we certainly believe that the laws of Nature govern everything, recognizing repeating and organized patterns is not always so easy. One of the classic examples of this is the tale of wealthy Bostonian Percival Lowell, whose imagination was captured in 1877 by the announcement of Italian astronomer Giovanni Schiaparelli that he had observed canali (Italian, “channel” or “groove”) on Mars. Many people’s inexperience with the Italian language caused them to map the word onto the English word “canal” which has a definite connotation of being an artificial and constructed edifice. (This erroneous mapping of words between one another is a failure to correctly match patterns!).

Lowell was entranced by the idea of canals on Mars, and spent a not inconsiderable amount of money constructing what is now known as the Lowell Observatory in Flagstaff, Arizona. He himself spent many long hours at the eyepiece, staring at Mars and sketching what he saw. Looking at his sketches and records we find Lowell saw what he wanted to see — canals. Lots and lots of canals. Looking at Lowell’s exquisite maps of Mars a century later, after our robotic spacecraft have returned tens of thousands of pictures of Mars, we see none of it. The interwoven pattern of canals which Lowell saw appear to be a dramatic case of scotomathe mind sees what it wants to see.

(L) Percival Lowell observing on the 24-inch Clark Refractor at Lowell Obseratory. (R) Lowell's map of the canals he thought he was seeing on Mars, now a classic example of seeing patterns that are, in fact, not there at all. [Images: Wikimedia commons]

(L) Percival Lowell observing on the 24-inch Clark Refractor at Lowell Obseratory. (R) Lowell’s map of the canals he thought he was seeing on Mars, now a classic example of seeing patterns that are, in fact, not there at all. [Images: Wikimedia commons]

Which carries us back to the tale of Blake and Trusler. We all see the world through our own eyes. The goal of collecting knowledge and one of the purposes of doing science is to capture the world as it really is, and to use that knowledge to improve our lives. No single one of us can do it all on our own; it requires all minds on deck. No single one of us ever gets it right on first glance; we have to look at the world, examine what we have seen, ponder its meaning, and, if necessary, let go of what we once thought in favor of a more real picture of what Nature has laid out before us.

So head out and look for the subtle patterns in the Cosmos; it’s all there for you to see.  See you out in the world — I’m the guy trying to take a picture of the repeating tile pattern on the cafeteria floor! 🙂

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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.