Tag Archives: climate change

Journey to a Northern Ocean

by Shane L. Larson

Polar bear on the shores of Hudson Bay, near Churchill, Manitoba. [Image: S. L. Larson]

I’m an active professional scientist and also a university professor. One of the things about my job that I enjoy the most and take quite seriously is the opportunity to talk with everyone about science. We talk about why science is an important human endeavour, how science impacts our daily lives, and how science helps us to improve our lives. We also talk about how science helps us understand the world around us, and what our purpose in the world is. At the end of October, I had the great opportunity to join a trip to the shores of Hudson Bay to observe the annual congregation of polar bears waiting for the return of the sea ice. Ostensibly I was there to give a science talk about the aurora borealis, but I was also representing my university with the group of travellers who were largely our alumni. Our destination was Churchill, Manitoba.

Churchill has a thriving tourist industry that in the early winter focuses on polar bears, and in summer focuses on beluga whales that congregate in the Churchill River; many businesses exist to help people experience these aspects of the natural world (we were hosted by the Lazy Bear Lodge). While people come for the wildlife, there is a lot to see in the area.

I was there late in the fall, on the verge of winter; walks on the shores of Hudson Bay were fun, but the weather was bleak and the landscape was windswept and cold. The surfline was beginning to freeze, leaving long gelatinous burms of frozen seafoam as the tides receded, a harbinger of the coming ice.

The shores of Hudson Bay, at the onset of winter. The foam from the surf is freezing at the high tide line. [Images: S. L. Larson]

Outside town there is a crashed Curtis C46 Commando, known to the locals as “Miss Piggy.” It went down in 1979 trying to return to the Churchill airport after its port engine went out on take-off. Miraculously, everyone walked away from the crash, but the plane is still there on a hillside outside of town.

Miss Piggy is the wreck of a Curtis C46 Commando, left where it crashed in 1979, on the outskirts of Churchill, just north of the airport. [Images: S. L. Larson]

 To the east of town, near the mouth of Bird Cove are the hulking remains of a derelict ship known as the Ithaca. It ran aground in 1969 during a storm, after 47 years at sea; the crew walked ashore at low-tide, and the ship was left to rust away into oblivion.

The wreck of the Ithaca, grounded at the mouth of Bird Cove since 1969. [Image: S. L. Larson]

All of this and more exist in the region, but we were there to see polar bears. The scientific name for polar bears is Ursus maritimus, Latin for “sea bear,” because the bears spend much of their lives on the arctic sea ice, largely in the areas where it interfaces with the land that fronts the Arctic Ocean. The area around Churchill is the home of one of the 19 recognized sub-populations of polar bears, numbering around 1000 individual bears. The story of why there is a population of bears in this area is a magnificent tale of biology, the planet, and the changes of the season.

The boundaries of the 19 recognized individual polar bear populations. [Image: C. Brackley, Canadian Geographic]

Polar bears are generally classified as carnivores, but they are perhaps more properly called lipidivores — their main sustenance is fat, primarily the fat of seals. Seals are primarily sea-going, occasionally crawling out onto rocks during the warm season and frequenting the surface of the ice in the cold seasons. The bears have the easiest time of hunting during the cold season, when they can stalk seals on the ice.

Polar bears are well adapted to life on the ice and in the sea. These bears were at Assiniboine Park Zoo and Leatherdale Polar Bear Conservation Center in Winnipeg. [Images: S. L. Larson]

Polar bears are well adapted to a life on the sea ice, with insulative fur and wide paws suited to walking on snow and ice. Their feet sport large claws and stippled pads for traction on frozen surfaces. They have insulative layers of fat that keep them warm when they are swimming in cold arctic waters. Compared to their cousins, the grizzly bears or brown bears, polar bears have long conical heads and necks, well adapted to lunging through breathing holes on the ice and hauling out a seal.

During the northern hemisphere winter, Hudson Bay is frozen over. The sea ice extends down from the arctic cap to the north and merges with shorefast ice that forms all along the coastline. During this time of year, the polar bears live on the ice, hunting seals. It is estimated that during this time, polar bears consume about 75% of their yearly intake of food, processing and storing it away as fat reserves for the ice-free season.

The average seasonal ice coverage on Hudson Bay. Red is the thickest ice, blue is open water. [A] June 18; with the onset of summer ice begins to recede across Hudson Bay. [B] July 30; by midsummer the last shorefast ice is gone, and the bears have come ashore in southern Hudson Bay. [C] September 17; around this time, arctic sea ice has reached its minimum extent. [D] November 5; by the start of November, shorefast ice begins to form in the Churchill region [E] November 26; the ice season has begun, and the polar bears migrate out onto the sea ice. [F] January 1; deep winter and the whole of Hudson Bay is frozen. (Images: Environment Canada)

What happens in the ice-free season? The ice recedes from the center of Hudson Bay, with the shorefast ice in the vicinity of Churchill being the last to disappear. The slow, seasonal recession of the ice drives the Churchill polar bears off the sea and onto the land, where they roam the boreal forests and tundra during the Arctic spring and summer. During this time of year, their primary food source — the seals — remain at sea and are more or less inaccessible, so the polar bears embark on a seasonally enforced fast while they are landbound. They will eat some vegetation, and possibly feed on carcasses if they happen upon them, but they consume little in the landbound months because their biology is largely optimized for the consumption of fat.

While they are landbound, waiting for the return of the sea ice, the bears wander around, and can sometimes be seen! [Image: S. L. Larson]

The Churchill population of polar bears comes off the sea-ice across the shores of Hudson Bay in northern Manitoba, but as summer wears on toward fall they migrate to the area around the Churchill River estuary. More than a mile across at the mouth, the Churchill River drains a large area of Alberta, Saskatchewan, and Manitoba into Hudson Bay, about 1.2 million liters (around 317,000 gallons) of freshwater on average each second. Fresh water freezes at higher temperatures than salt-water, so the large flow of freshwater into Hudson Bay from the Churchill River insures the sea-ice appears around the river outlet first, in late October and early November. The polar bears have learned this, and their seasonal circulation brings them to the area around Churchill when the first ice appears, so they can head out onto the bay and start their seasonal feeding again.

When the polar bears are landbound, they do not expend tremendous amounts of energy. This bear was started by humans who were trying to scare it away from their home. [Image: S. L. Larson]

This seasonal pattern of feeding and fasting has influenced other aspects of polar bear biology, particularly with regard to young bears. Polar bears mate in the spring (mostly in April and May), while the bears are still on the sea ice. The females experience a delayed impregnation — after mating, they harbor fertilized eggs that do not implant or begin developing. In late September, around the time the sea-ice is reappearing, a female polar bear’s body makes an assessment of how much fat reserves she has; if it is enough, the fertilized eggs implant, and the embryos begin to develop. The gestation period is very short — only about three months. During this time, the female bear begins to look for an area to den. In the Churchill area, she typically excavates a large, protected hollow in the peat that covers the northern shores of Manitoba above the permafrost layer. Sometime around December or January, cubs are born. Generally two cubs are born, but singles or triplets are not unheard of. The cubs are feeble and small when they are born, usually around half a kilogram, covered in short fur but blind and toothless.

A mock-up by Parks Canada of a mother bear, denning in the peat with her cubs. [Image: S. L. Larson]

The mother bear remains in her den with her new cubs for several months, continuing the enforced fast that began when she came ashore with the vanishing of the sea-ice the previous spring. The cubs nurse, growing rapidly on a diet of milk that is typically about 31% fat. Within a few months, the cubs have grown to about 10-15 kilograms, have developed thicker fur coats, and are able to move around. With the arrival of spring, the mother leads them out onto the sea-ice. This is usually around the time the seals have delivered their own pups. Seal-pups are born on the ice, and spend about eight weeks of their early days in dens in the ice and snow, near breathing holes their parents use to access the sea. The pups, despite being covered in snow dens, are not quiet and make easy prey for the polar bears. Uncovering the poorly protected pups in large quantities provides an easy, exploitable source of food for a mother bear to rapidly grow her cubs before they are forced off the sea-ice in the summer months. For the seals, vast numbers of pups insure they survive this season of hunting by bears.

Schematic of a seal pupping den. The adult seals access the den from a breathing hole; the pups live out of the water, but under a crust of snow that polar bears can break through.

All told, in our two days on the tundra, we saw five bears. The last bear we saw had been tranquilized and was being airlifted to the Churchill Polar Bear Holding Facility, where it will be held for a week or more and then released far from town (ideally so it can move onto the sea ice, once it forms). Managing the interface between people and bears is part of life in Churchill. For the most part, the bears are not habituated to the humans, but they are sometimes captured and moved away from town to protect both people and the bears themselves. The bear we saw being airlifted was near town on the afternoon of Halloween — we suspect the action was taken to prevent a bear from thinking that a trick-or-treater was a delectable substitute for a seal pup.

[left] A red fox we saw; sadly, we saw no arctic foxes. [right] The best ptarmigan picture I could get! (Images: S. L. Larson)

The tundra is replete with other life as well. In addition to the bears we saw several red fox, as well as plethora of birds (including ptarmigans). My favorite other animal we saw were lemmings frolicking in a snow bank, but they are frickin’ fast and difficult to photograph. 🙂

The remoteness of this area is not to be underestimated. The town of Churchill has a population of about 1000 people. Historically, the area has been populated by indigenous people, notably the Cree and the Dene. Europeans came to the area in the 1600s, when the Hudson Bay Company built the Prince of Wales Fort at the mouth of the Churchill River, across the estuary from the location of the modern town. The port of Churchill affords access via sea during the short ice-free months. Rail service has traditionally existed, running through the forests and tundra of northern Manitoba from Churchill to Winnipeg. During the spring of 2017, many sections of the rail line have been washed out, and it is uncertain if they are going to be repaired or if the rail line will be abandoned in place. In light of this, the only reliable access to the town is via air.

Aerial view of Churchill, with the Lazy Bear Lodge in the foreground. (Image: Wikimedia Commons)

For those of us who grew up in small towns, or in remote parts of North America, Churchill feels like a typical small town — people know almost everyone in town; there is only a small business district; lots of cars and trucks that are decades old instead of a year or two old; there are only a couple of roads and few multi-lane highways. The wilderness is within walking distance of anywhere in town.

To the southeast of Churchill, hugging the shores of Hudson Bay, is the Wapusk National Park (“Wapusk” is a Cree word for polar bear), but it is not a park like Yellowstone or Banff, criss-crossed with roads and full of amenities for people who seldom emerge from urban areas. Wapusk National Park has no roads leading into it, and encloses the largest protected polar bear denning area in the world. It is 11,475 square kilometers of boreal forest and tundra with more polar bears than people who frequent it.

Maps showing Manitoba, Churchill, and Wapusk National Park. (Maps: Parks Canada)

Nestled as it is on the shores of the northern ocean, the area around Churchill and Wapusk National Park are an ideal region to study and understand the changes our planet is experiencing, particularly as anthropogenic activities drive the global climate to warmer temperatures. Already the seasonal cycles of ice growth and recession are noticeable in the Churchill area, with sea-ice forming later in the fall and melting earlier in the spring by measurable lengths of time. This expansion of the ice-free season is part of the larger pattern of global arctic sea-ice decline.

Graph showing the projected decline in arctic sea ice as Earth’s climate warms. The grey and black show model predictions, and the red line shows current observations. [Graph from National Snow and Ice Data Center]

These kinds of environmental changes ripple through the ecosystem of the area, particularly the polar bears — a shortening of the sea-ice season is a shortening of the season where they do most of their feeding and building of fat reserves, complemented by a longer fasting season. Worldwide, there are growing numbers of bears who are starving or in declining health. Currently the Churchill polar bear population appears to be stable, though other bear populations in the arctic are declining. Whether or not the global polar bear population is stable or not is highly uncertain, since a significant portion of it inhabits the shores of Siberia, and the Russians are not forth-coming with environmental data about their area of the world.

If you are a scientist who would like to study ecology, or climate, or wildlife in the tundra and boreal forests of the region, Churchill is also home to the Churchill Northern Studies Centre. The Centre is a scientific and educational institution dedicated to a deeper understanding of life in the north — the physical environment, the ecology of the flora and fauna, and the interface with humans and human cultures. The Centre resides on the grounds of the Churchill Rocket Range, which used to launch sub-orbital sounding rockets to study atmosphere and aurorae, housed in a modern LEED certified building, with lab and workspace for scientists, and residential space that allows you to come and stay for weeks at a time while working at the center.

I was in Churchill for only 3 days, and barely scratched the surface of what there is to see and experience in this remote part of the world. Beyond the ecology of the polar bears, the summer months bring vast migrations of beluga whales who birth their young in the Churchill River. The area is part of the wide territories of the indigenous people of the Arctic that have inhabited these lands for thousands of years. Sitting on the boundaries of the Arctic, the area is showing and will continue to experience the early and rapid onset changes brought on by the changing climate, and represents an area where a person can learn and focus attention on this pressing problem.

I’ve been home for a month now, but I still think every day of those windswept days I spent on the shores of the Northern Ocean. I’m going to have to go back, sometime soon.

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Cosmos 13: Who Speaks for Earth?

by Shane L. Larson

Let me tell you a story about me that many people don’t know. When I was in junior high school, I was a small, exceptionally nerdy child who loved Star Trek, science, games of all sorts (provided they didn’t involve “teams” or “athletics”), and learning. My very best friend of the day was a similarly minded young gentleman, who introduced me to computer gaming (“Colossal Cave”, which we played on the mainframe at Ball Aerospace, where his father worked), World War II aircraft, and car mechanicing. He also had epilepsy. It was frightening when he would have seizures, because he would go blank and suddenly it was like he didn’t know me or anything about the world around him. I don’t recall how long these episodes would last, but what I do remember is his father would swoop in, and sit with him for time, and eventually my friend would be back, and we’d be off to explore the world again.

A scar on the orbit of my left eye; stitches in my 7th grade year. The scar has faded slowly over the years, but is still obviously there if you know to look for it.

A scar on the orbit of my left eye; stitches in my 7th grade year. The scar has faded slowly over the years, but is still obviously there if you know to look for it.

Now, as was often the case in the cruel world of middle-school aged children, we were the target of bullies. My locker neighbors reveled in shutting my locker each time I opened it, or knocking all my books on the ground so I was tardy to next period. Once they took my prized possession of the day, the Collected Novels of H.G. Wells; when I decided that day to fight back, I was bodily thrown across the room into a metal chair, gouging myself on the orbit of my left eye, requiring 7 stitches and leaving a scar I still have today. My best friend was a similar target, with more serious consequences because the physical bullying would often trigger a seizure. The school administration took an all too common viewpoint on these matters: no one saw it, so it is your word against theirs. An odd viewpoint in light of the amount of blood streaming down my face (I don’t know what the bully had told them, but to be fair I had bit him when he had me in a headlock).

Me and my family, in my high school years. My mom and dad instilled in all three of us boys a robust sense of justice.

Me and my family, in my high school years. My mom and dad instilled in all three of us boys a robust sense of justice.

Now my parents are the most moral, upstanding people I know, and taught me a deep personal philosophy about justice. Now, in the wisdom of my adulthood, I like to hang quotes from Gahndi on it, like “It is better to be violent, if there is violence in our hearts, than to put on the cloak of nonviolence to cover impotence.”  But really, what I remember are words from my Pa: “Bullies are really just cowards, so knock them down. And make sure the bastards don’t get back up.”  The matter all came to a head on a late winter day during my 7th grade year. My best friend had his head bashed against a locker, which triggered a bad seizure. No teacher saw it happen, but I resolved it was going to stop.  At the end of lunch period that day, I bought an extra milk, and opened the carton on both sides. I remember one of my other nerdy-friends standing next to me saying, “Aw, how are you going to drink that now?” I didn’t answer; I was standing behind the locker-basher, who was sitting at a table. I upended the carton of milk over his head, and beat the tar out of him. The event instigated one of the largest food fights the junior high school had ever seen, and I was awarded a 2-week suspension, which I took without argument.

One of the most often reproduced Apollo images; Jim Irwin on the plain at Hadley, in front of the Lunar Module Falcon and Lunar Rover. [NASA Image AS15-88-11866]

One of the most often reproduced Apollo images; Jim Irwin on the plain at Hadley, in front of the Lunar Module Falcon and Lunar Rover. [NASA Image AS15-88-11866]

The aftermath was the most important. My friend and I were never the target of these particular bullies again; nor were we the target of a somewhat wider group of bullies who had always circled on the fringes of our lives. This kind of mayhem was far outside the boundaries of what was expected from me. The event somehow incited some people to ask what really happened, and to pay attention. After a long discussion with the faculty advisor about the event and the reasons behind it, my National Junior Honor Society membership was maintained. My suspension was lifted a week early, so my friend and I both could attend a school assembly featuring Apollo 15 astronaut Jim Irwin, whom we met and talked with! But most importantly, my science teacher docked my term project about the anatomy and life cycles of frogs from a 100% to an 80%, dropping me a letter grade in the class. It blemished an otherwise admirable middle-school academic record. She never said a word, and just kept right on treating me like the scientist she seemed to know I was going to become. She reinforced a lesson my parents had already touted — there are always consequences, even when you are doing the right thing, but it shouldn’t stop you from doing the right thing.

Now, in my adulthood, I still carry that same overbearing, black and white opinion about justice, and an unfailing opinion that people who can stand up should stand up for those who can’t. It is something that I often think about as I push my way blindly forward in my career.  What do I do everyday, when I’m not writing this blog for you to read?  I’m a scientist; an astronomer. What does that have to do with bullies and childhood scraps? Everything in the modern world.

A white dwarf is the skeleton of a star like the Sun, long after it has died. It has about the mass of the Sun, but is the size of the Earth. [Image by STScI]

A white dwarf is the skeleton of a star like the Sun, long after it has died. It has about the mass of the Sun, but is the size of the Earth. [Image by STScI]

In my everyday life as a professional scientist, I spend my time thinking about astrophysics, exploring our understanding of how gravity influences the evolution and life of white dwarf stars, the ancient cooling skeletons of stars that lived their lives like the Sun. Some days, I teach intro science classes to young women and men bound for careers in business, medicine, law and management; people who may never take another science class in their lives, nor think all that much about science ever again. Every now and then, one of them asks me, “What is understanding white dwarfs good for?” There are a whole host of reasons related to how stars act as astrophysical laboratories, simulating conditions that are difficult and expensive to replicate on Earth, and how the knowledge has applications to technology, energy, and medicine.  But the real reasons, the important reasons are these:

(1) Astronomy, unlike bench science in a laboratory, in an exercise in looking, thinking, and understanding Nature from afar. The practice of astronomy teaches us how to think deeply about the Cosmos, how to unravel the secrets of Nature, and not fool ourselves into thinking something false. More than any other science, astronomy teaches us to be harshly critical of our reasoning, to be brutally honest about what we know and don’t know, and to be quite certain of our conclusions when we say them out loud.

secretCancer(2) Every person has a deep seated sense of wonder, waiting to be ignited and tapped. We cannot know who or what will inspire those who see the future for us, but we know it will happen, just as it has happened in the past to people named Steve Jobs, Temple Grandin, Dean Kamen, Rachel Carson, and a thousand others. We explore, learn, and teach the wonder of the Cosmos with the certainty that it can and will inspire someone someday to consider a life in science and technology, a life in service to our species and our planet. The consequences of not teaching people about the wonders of astronomy are almost too awful to contemplate. What if the next Newton never discovers science? What if the cure to cancer is hidden inside someone who is never inspired to continue their education?

(3) Lastly, in a world increasingly dependent on science and technology, science has become a weapon.  Not a a tangible device of destruction (though there are certainly plenty of examples of those), but a psychological bludgeon used to prey on those who have weakness or uncertainty in the realms of science and evidence based reasoning. The Earth faces an uncertain future in terms of its long term evolution, and the survivability and impact of our species on this planet. Special interests, driven by economics, politics, or ideology, have become the bullies of the modern world. Their tactic of choice is the subversion of knowledge and evidence-based wisdom, using modern media to sow uncertainty and discontent, holding the world hostage in a constant state of confusion and embittered debate. The weapon against those with shallow vision and self-serving interests is critical thinking, and common cause.  For the first time in all the history of the Earth, we have both. The practice of science is the human species’ profound realization of the process of critical thinking; it’s only goal, is to seek the truth with unflinching respect for the evidence and facts. Technology has given us the ability to communicate, directly and personally, with every person on the planet.

In a 1990 essay for the Committee for Skeptical Inquiry Carl Sagan wrote, “We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.”  This is a trend that has not changed in the two decades since; if anything, it has become exacerbated as technology and mobile technology has interlinked our world and become enmeshed with our daily lives.

Smartphones and carburetors, two of the great mysteries of the modern world. Making sure everyone can explain their inner workings is not the goal of science literacy.

Smartphones and carburetors, two of the great mysteries of the modern world. Making sure everyone can explain their inner workings is not the goal of science literacy.

The danger is not that people don’t understand the workings of a smartphone touchscreen or the purpose of a carburetor.  No, the true danger lies with people being told what they should think about a complex and interconnected world, instead of being able to think critically about how trustworthy the information being passed to them is. The best way for the citizenry of the Earth to protect themselves from charlatans is to know how science works. The second best way is for scientists to put some more skin in the game.

Science cannot be limited to those who practice it; it cannot be an esoteric playground of wonder and imagination for the privilege of a few.  What scientists know must be explained and popularized for the citizens of the world; people must understand that the purpose of science is to improve their lives, and it has.  Modern medicine has erased crippling diseases, satellites girdle the world providing a never-ending stream of data about the weather and evolving state of the planet, and telecommunications technology has deprovincialized knowledge to build a global community. The world-spanning internet has made communications instantaneous and egalitarian, exposing a vast fraction of the world to the wisdom and art of our species, but also connecting all of us instantaneously to the abject horrors our race is capable of, and showing the implacable forces of Nature casually destroying human constructs. Science is all around us.  It is not perfect, but it has repeatedly demonstrated an unfailing ability to change the world.

There are plenty of vocal scientists and active science communicators.  Phil Plait (twitter: @BadAstronomer) is a robust opponent (among many other things) of the anti-vaccination lobby. James Hansen and Michael Mann (twitter: @MichaelEMann) are prominent faces in the battle against climate denialism. Jennifer Ouellette (twitter: @JenLucPiquant) writes and blogs tirelessly about science and mathematics.  But there need to be more — many more. It is estimated that only 5% of the labor force in the United States are practicing scientists or engineers. That is an extraordinarily tiny fraction, so there is a challenge for everyone.

Richard Feynman

Richard Feynman

On the part of the scientists, the challenge is to talk with your neighbors, talk with your friends, talk with anyone who will listen. There has been a slow and steady decline in the public percpetion of the value of scientists and academics in general.  This has been widely discussed recently in light of an excellent OpEd by Nicholas Kristof. Many academics have taken great affront to this article, but as I tell my 7-year old: how you act is up to you, but how people think you act is up to them. If you want people to change how they think of you, then you have to change how you act (especially when they are watching). In this case, many many decades of unremitting dedication to the urbane life of an academic, steeped in our own traditions and mindsets, have burned bridges that should never have been severed. Scientists are particularly bad at this, and we see the results — charlatans are slowly eroding public confidence in science to the point where despite overwhelming evidence, people don’t know what to think about the future of our planet or species. Richard Feynman always said, “Science is what we do to keep from lying to ourselves.”  Our job is to help people understand that.

George Bernard Shaw.

George Bernard Shaw.

On the part of everyone else, the challenge is learn to think critically, just as you do with everything else in your lives — you are the ones who are going to decide the future of our civilization, with your money, your actions, and your votes. Talk with your neighbors, talk with your friends, talk with your children.  Honor the wisdom of George Bernard Shaw, who admonished us to “Beware of false knowledge; it is more dangerous than ignorance.” We are being bullied, scarred for life, and we don’t even know it.  Forces within our society think they can play on our fears, for their own benefit, by encouraging us to doubt and deny our hard-fought ability to reason.  It’s time to fight back against these nebulous and callous forces, with the most powerful weapon we have: science. Denial of science is a denial of our birthright, an abandonment of a legacy of 40,000 generations of human beings who have walked before us.

With all the long future days of our planet and our race in front of us, there is but one task before us: preserving the lives of the citizens of the Earth, be they human or not, and ensuring the future habitability of this planet, the only place in the Cosmos we know, with certainty, where any form of life can and does survive.

We speak for Earth, you and I.  Our loyalties are to the species, and the planet. We speak for Earth. Our obligation to survive and fluorish is owed not just to us, but to the Cosmos, ancient and vast, from which we spring.

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Final Note: This closing quote, is the closing quote from Cosmos as well. Thank you, Carl, for a journey that defines much of what I think, say, and do every day of my life. From the stars we came, and to the stars we shall return, now and for all eternity.

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This post is part of an ongoing series, celebrating the forthcoming science series, Cosmos: A Spacetime Odyssey by revisiting the themes of Carl Sagan’s classic series, Cosmos: A Personal Voyage.  The introductory post of the series, with links to all other posts may be found here:  http://wp.me/p19G0g-dE