Sagan Mashup

via ajboyer on Twitter.

Solstice

Dr. Sagan on the solstice.

Everything I Needed to Know About Life...

Everything I needed to know about life, I learned from Carl Sagan.

When I was only ten years old, "Cosmos" began on PBS. I met my hero once a week and he told me that there was so very much more to life than I knew. He told me that life was precious and that if we were not careful, it could all slip away. He told me things that the people who run the world have yet to learn or implement. I became a student of his works and have tried to make a difference in this world. Carl Sagan is my hero.

Miles

Celebrating Carl Sagan

Though I was only introduced to Carl Sagan by my high school friends about eight years ago (unfortunately after his passing), I quickly became, and to this day still am, an avid fan.

My favorite DVD set that I own is his PBS documentary Cosmos. While I already loved astronomy, after I discovered Sagan, my interest increased even more.

In a nutshell, I think it is Sagan's eloquent, yet simple explanations of astronomy that make him so unique. He is excellent at helping to comprehend a science that is, often times, incomprehensible.

RIP Carl Sagan. You taught us so much.

- Mike Postiglione, Kansas

Remembering Dr. Sagan

As a ten-year-old boy flat on my stomach, head propped up in my hands, watching “Cosmos” on television, Carl Sagan showed me “the joy of figuring things out.” I learned that there is just as much adventure in the real-life dramas of sending robotic probes to new worlds (well, new to us, anyway) and that “Eureka!” moment when a mystery becomes solved, and, paradoxically, the simultaneous revealing of myriad additional mysteries, as there were in the science fiction and fantasy works that I loved so much.

I’ve never lost my love for that moment of gaining a little more understanding and becoming a little more at home in the Cosmos, and more than anything else I wanted to share it with as many people as possible. I became a high school teacher of physics upon graduating from college, and I haven’t looked back.

More than anything else, I am grateful that I was able to share with Drs. Sagan and Druyan what they were able to give to me. A book signing for Shadows of Forgotten Ancestors at Oxford Books in Atlanta, GA gave me the opportunity to personally thank Carl Sagan for giving me such inspiration and for flagging this path for me to follow.

My dream is that maybe one of my students who may never even have heard of Carl Sagan might catch the fever and pass it along themselves.

Michael Poley, Physics and AP Physics Teacher,Holy Innocents’ Episcopal School

Celebrating Indeed.

Ever since I picked up the Cosmos book from my parents' bookshelf at a young age, Astronomy has been a passion of mine (I almost studied Astrophysics after reading Sagan led me to Hawking, before opting for CompSci). The book absolutely fascinated me. As I got older and continued to read the book, my world view was shaped to look at everything from the top down, starting with the big picture -- which has made me very successful in my career as an IT professional.

I plan to pass the book, DVD collection, and whatever else I can on to my children.

Thanks, Carl. You will always been remembered as my first non-fictional childhood hero.

Jeff, Jacksonville, FL

The Drake Equation

N = R_* f_p n_e f_l f_i f_c L
Where,
N = The number of civilizations in The Milky Way Galaxy whose radio emissions are detectable.
R_* = The rate of formation of stars suitable for the development of intelligent life.
f_p = The fraction of those stars with planetary systems.
n_e = The number of planets, per solar system, with an environment suitable for life.
f_l = The fraction of suitable planets on which life actually appears.
f_i = The fraction of life bearing planets on which intelligent life emerges.
f_c = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
L = The length of time such civilizations release detectable signals into space.

From SETI's Carl Sagan Center for the Study of Life in the Universe - try out their Drake Equation Calculator.


There are a lot of moments in Cosmos that widened my perspective when I first watched the series. Episode 12, Encyclopedia Galactica, is filled with such moments. In the clip below, just before he launches into his vision of the Encyclopedia Galactica, Sagan addresses the probability of intelligent life in the galaxy using the Drake Equation.

Even for a person with a rudimentary understanding of mathematics like myself, the Drake Equation is a simple way to explore the potential for life in the vast Milky Way, which is always a good time. In the clip, Sagan walks us through the equation, demonstrating just how hard it is to know whether we are alone and unique in the universe, or just pedestrian intelligent life. It ends with a humbling thought:

So if civilizations do not always destroy themselves shortly after discovering radio astronomy, then the sky may be softly humming with messages from the stars, with signals from civilizations enormously older and wiser than we.

He goes on from there to succinctly summarize the central plot of Contact, and leaves us reflecting on the great value of radioastronomy and it's potential to aspire us to take to the stars:

If there are millions of technical civilizations in the milky way, each capable of radio astronomy, how far away is the nearest one? If they're distributed more or less randomly through space, then the nearest one will be some two-hundred light-years away, but within two-hundred light years, there are hundreds of thousands of stars. To find the needle in this haystack requires a dedicated and systematic search.

There are many cosmic radio sources having nothing to do with intelligent life, so how would we know that we were receiving a message? The transmitting civilization could make it very easy for us if they wished. Imagine we're in the course of a systematic search, or in the midst of some more conventional radio observations, and suppose one day we find a strong signal slowly emerging. Not just some background hiss, but a methodical series of pulses. The numbers: 1, 2, 3, 5, 7, 11, 13. A signal made of prime numbers; numbers divisible only by one and themselves. There is no natural astrophysical process that generates prime numbers. We would have to conclude that someone fond of elementary mathematics was saying, "Hello." This would be no more than a beacon to attract our attention. The main message would be subtler, more hidden, far richer. We may have to work hard to find it.

But the beacon's signal alone would be profoundly significant. It would mean that someone had learned to survive technological adolescence, that self-destruction is not inevitable, that we also may have a future. Such knowledge, it seems to me, might be worth a great price."

If that doesn't open up your mind, well, you must have it closed pretty tightly.