This weekend I gave a talk at BIL (the younger brother of TED). Here's a transcript of it, which I entitled "What is out there? - An astronomer's view on exploration and discovery". I usually give talks the scientist way: slides, endless rehearsal, no notes. This time around, however, I was reading verbatim from a speech I had prepared in forehand. Not a bad way to give public talks, I suppose. When the video is out, I'll link it here.
============== x ==============
Thank you. I would like to start today by telling you a little personal story. I am astronomer, and I can pinpoint exactly when I decided to be an astronomer. I was five years old. I have two big sisters. Big sisters can be a pain, as some of you may know. But I own my middle sister something very important. When I was five, she was nine, she was already at school, so she had books. Back in 1987, her bookshelf was the closest I had to wikipedia.
Once, I took a look at her science book, of 3rd grade of elementary school. And I saw a drawing similar to this. A sketch of the Solar System. This image hit me with a force I can barely describe. I recognized the Earth, the Moon, and the Sun, but I got myself wondering about the other little spheres. What were they? Are they worlds like the Earth? If so, how similar? Are they different? How different? I needed to know. At that moment, at age five, I decided my career.
.jpg)
If I believed in reincarnation I would say I was an astronomer in my past life. Because how can someone look at a sketch like this, and become hooked on it, and develop a lifetime interest within five seconds of staring at it. Trouble is, I do not believe in reincarnation. The mental process that struck me is related to one of the ancient questions that humankind has always pondered itself. "What is out there?"
Looking at our history, it is patent that our species has an instinct for exploration. More than 2000 years ago the Phoenicians travelled from the East Mediterranean, entering the Atlantic, then north to Great Britain. The Carthagians also travelled past Gibraltar, and went as far south as Cape Verde. And long before they knew of the Vikings, there were legends in Southern Europe about fantastic lands up north where the Sun was said to shine at midnight.
I would like to share with you here today something that bothers me a little. As a scientist, one of the cores values I follow is to give credit where credit is due. So, it kinda bugs me that when the subject of the Age of Discovery pops up in a conversation, pretty much the only name that comes to people's mind is Columbus. Perhaps Magellan, and maybe Cook. But few will mention Bartolomeu Dias, or Vasco da Gama. The world seems to have forgotten that the first ships to defy the oceans set sail from the shores of Lisbon. Back in the early 14 hundreds, the Portuguese prince, Prince Henry the Navigator, was kinda of a President Kennedy with a we're gonna land a man on the Moon speech. With the difference that space was the oceans, and the Moon was India.
There are some parallels indeed. They had to build new technology, the caravel, a light, highly maneuverable ship that could sail in open ocean. There was external pressure, and international competition. There was the epic thrill of exploration. And there was also success. In less than a century, Portuguese navigators had rounded the cape of Good Hope and reached India, China, Japan. In less than four hundred years after the death of Prince Henry, every shore in the world had been visited by an European ship. It is an amazing feat, sang in poetry. Oh salted sea / how much of thy salt / Are tears of Portugal!, say the opening verses of a poem by one of their national poets *. They have all reason to be proud of they seafaring legacy, much like the Greeks with their legacy of science and philosophy.
Obviously, what you will read in the history books is that Prince Henry's chief motivation was to establish new routes to the Silk Road and the Indian spice trade, that were now blocked by the Ottomans. Yet by studying his biography what strikes the most is the fascination and curiosity that Prince Henry seems to have had. One thing in particular I found very intriguing, and I could kinda identify with. He tells of seeing a map when he was child of the known world at the time, and developing a lifelong fascination with Africa. One can pretty much imagine young price Henry staring at this map, recognizing his native Portugal, Spain, Italy, Greece and the Mediterranean, curious about the fantastic East of Marco Polo, but above all, struck in awe by the apparent boundlessness of Africa. How far away did that land extend? Did it go all the way to the south pole? Was there a passage to the Indian ocean? Or was the Indian ocean landlocked? In this vast land, were there kingdoms like in Europe? He needed to know. Sure Prince Henry had political and economic reasons to set sail, but that was not the whole story. He needed to know what I needed to know. What is out there? Maybe the map he saw was in the schoolbook of his big sister.
That image of the solar system brought home to me that our Earth is one among a family of planets. Such a simple concept! So simple, that to me it comes as a terrifying demonstration of the folly of human imagined self-importance, who arrogantly denied the idea multiple times through history when presented with it. This is in my opinion the greatest contribution that the study of astronomy brings. Cosmogony and Cosmology, both defined in a broad sense. How did the Earth come to be? What is the big picture? How do we fit in it? Virtually every culture known to antropology, every society in recorded history, has at some point asked these questions in one form or another. Our quest to understand the skies is a quest to understand ourselves.
It was with this thirst to refine our worldview that much of our Astronomy has been made. There was a time when we had no idea whatsoever of the nature of the Sun. The first philosopher who said the Sun was not the charriot of a god got into big trouble. People were outraged by his suggestion that the Sun was a hot rock as big as the south of Greece. Our realization that the Sun is a star was a difficult road. Perhaps because the obvious implication is hard to grasp at first: the stars are suns. Little by little, we figured out what was out there. We made out the shape and nature of our home. A flat gigantic disk of billions and billions of suns, where distances are so great that they are measured in light years. Then we discover that our galaxy is not the only one, quite the opposite, it's but one among a good hundred billions of similar island universes. Feeling small? There are more stars in the Universe than grains of sand in all the beaches of planet Earth. Astronomy truly is a humbling experience.
Thank you. I would like to start today by telling you a little personal story. I am astronomer, and I can pinpoint exactly when I decided to be an astronomer. I was five years old. I have two big sisters. Big sisters can be a pain, as some of you may know. But I own my middle sister something very important. When I was five, she was nine, she was already at school, so she had books. Back in 1987, her bookshelf was the closest I had to wikipedia.
Once, I took a look at her science book, of 3rd grade of elementary school. And I saw a drawing similar to this. A sketch of the Solar System. This image hit me with a force I can barely describe. I recognized the Earth, the Moon, and the Sun, but I got myself wondering about the other little spheres. What were they? Are they worlds like the Earth? If so, how similar? Are they different? How different? I needed to know. At that moment, at age five, I decided my career.
.jpg)
If I believed in reincarnation I would say I was an astronomer in my past life. Because how can someone look at a sketch like this, and become hooked on it, and develop a lifetime interest within five seconds of staring at it. Trouble is, I do not believe in reincarnation. The mental process that struck me is related to one of the ancient questions that humankind has always pondered itself. "What is out there?"
Looking at our history, it is patent that our species has an instinct for exploration. More than 2000 years ago the Phoenicians travelled from the East Mediterranean, entering the Atlantic, then north to Great Britain. The Carthagians also travelled past Gibraltar, and went as far south as Cape Verde. And long before they knew of the Vikings, there were legends in Southern Europe about fantastic lands up north where the Sun was said to shine at midnight.
I would like to share with you here today something that bothers me a little. As a scientist, one of the cores values I follow is to give credit where credit is due. So, it kinda bugs me that when the subject of the Age of Discovery pops up in a conversation, pretty much the only name that comes to people's mind is Columbus. Perhaps Magellan, and maybe Cook. But few will mention Bartolomeu Dias, or Vasco da Gama. The world seems to have forgotten that the first ships to defy the oceans set sail from the shores of Lisbon. Back in the early 14 hundreds, the Portuguese prince, Prince Henry the Navigator, was kinda of a President Kennedy with a we're gonna land a man on the Moon speech. With the difference that space was the oceans, and the Moon was India.
There are some parallels indeed. They had to build new technology, the caravel, a light, highly maneuverable ship that could sail in open ocean. There was external pressure, and international competition. There was the epic thrill of exploration. And there was also success. In less than a century, Portuguese navigators had rounded the cape of Good Hope and reached India, China, Japan. In less than four hundred years after the death of Prince Henry, every shore in the world had been visited by an European ship. It is an amazing feat, sang in poetry. Oh salted sea / how much of thy salt / Are tears of Portugal!, say the opening verses of a poem by one of their national poets *. They have all reason to be proud of they seafaring legacy, much like the Greeks with their legacy of science and philosophy.
Obviously, what you will read in the history books is that Prince Henry's chief motivation was to establish new routes to the Silk Road and the Indian spice trade, that were now blocked by the Ottomans. Yet by studying his biography what strikes the most is the fascination and curiosity that Prince Henry seems to have had. One thing in particular I found very intriguing, and I could kinda identify with. He tells of seeing a map when he was child of the known world at the time, and developing a lifelong fascination with Africa. One can pretty much imagine young price Henry staring at this map, recognizing his native Portugal, Spain, Italy, Greece and the Mediterranean, curious about the fantastic East of Marco Polo, but above all, struck in awe by the apparent boundlessness of Africa. How far away did that land extend? Did it go all the way to the south pole? Was there a passage to the Indian ocean? Or was the Indian ocean landlocked? In this vast land, were there kingdoms like in Europe? He needed to know. Sure Prince Henry had political and economic reasons to set sail, but that was not the whole story. He needed to know what I needed to know. What is out there? Maybe the map he saw was in the schoolbook of his big sister.
That image of the solar system brought home to me that our Earth is one among a family of planets. Such a simple concept! So simple, that to me it comes as a terrifying demonstration of the folly of human imagined self-importance, who arrogantly denied the idea multiple times through history when presented with it. This is in my opinion the greatest contribution that the study of astronomy brings. Cosmogony and Cosmology, both defined in a broad sense. How did the Earth come to be? What is the big picture? How do we fit in it? Virtually every culture known to antropology, every society in recorded history, has at some point asked these questions in one form or another. Our quest to understand the skies is a quest to understand ourselves.
It was with this thirst to refine our worldview that much of our Astronomy has been made. There was a time when we had no idea whatsoever of the nature of the Sun. The first philosopher who said the Sun was not the charriot of a god got into big trouble. People were outraged by his suggestion that the Sun was a hot rock as big as the south of Greece. Our realization that the Sun is a star was a difficult road. Perhaps because the obvious implication is hard to grasp at first: the stars are suns. Little by little, we figured out what was out there. We made out the shape and nature of our home. A flat gigantic disk of billions and billions of suns, where distances are so great that they are measured in light years. Then we discover that our galaxy is not the only one, quite the opposite, it's but one among a good hundred billions of similar island universes. Feeling small? There are more stars in the Universe than grains of sand in all the beaches of planet Earth. Astronomy truly is a humbling experience.
But some of them should be remarkably similar to home. The first found were bigger than Jupiter, but as the accuracy of our instruments and techniques increase, smaller and smaller planets have been detected. The first Earth mass planet was announced two years ago. This month a planet the size of our Moon has been reported. We already know of a number of Earth-mass exoplanets in the Goldilocks zone of their star, the range of distances where liquid water can exist. Our next generation of telescopes will have the capability to assess if these planets have atmospheres, and determine their composition. This will enable us to look for signs of large scale biological activity. We may be less than ten years away from answering an age-old question: "are we alone?".
When President Kennedy said we would put humans on the Moon and return them safely to Earth, he was playing an old note. Apsley Cherry-Garrard, member of the British Antarctic expedition of 1912, and most memorable chronicler of the voyage, upon returning to England became a sort of expert writer on any subject pertaining to exploration. In the late 20s, he wrote something that I'd like to quote. He wrote that we would reach the Moon, and that in great likelihood we would do it in less than one thousand years. He could not foresee the political climate that led to the space race and allowed for the Moon landing only a couple decades thence. But even without the catalytic effect of the Cold War the Moon landing would probably have been achieved in much less time than he imagined. Perhaps right now, at our times.
Neal Armstrong passed away last year. Soon, there may come a time when no one alive on this planet will have walked on the surface of another world. There is no excuse, we need to go to Mars. And beyond.
This image shows the location of the exoplanets discovered so far. As you can see, the volume of the galaxy that we explored is very small. From this, we can infer that the galaxy should contain hundreds of billions of planets. More planets than stars, in fact. But these exoplanets close to us... they are special. Those within 100 light years are close enough that they will surely be part of our future. We will send probes there, we will land there. I risk to say that in great likelihood we will do it in less than one thousand years.
I started this talk mentioning the Portuguese, and even quoted one of their poets. I would like to close today by quoting another. Carl Sagan once wrote that the Earth is the shore of the cosmic ocean. For his birthday a couple years ago NASA invited people around the world to submit an essay inspired by that beautiful imagery. The one I liked the most among the finalists was submitted by a Portuguese guy**. He took the methaphor and evoked the navigant tradition of his people, writing that "we are now taking that pursuance a little farther. We shall cross the distance. Assume the distance. Be the distance. Nowadays, hot Jupiters and other almost unclassifiable sorts of exoplanets are our new deserts, our new abysses, but... somewhere there, in the distance, a new verdant valley awaits us. We are, once more, picking the staff. We are, once more, nomads, stellar nomads. The new worlds are there, in the distance, waiting for us. What unimagined islands, continents, other tribes await us? We simply don't know. What can there be beyond the curve in the path? We are sailing towards it, towards the horizon, towards the other shore. We are all discoverers, now sitting at the sand, contemplating the sea, waiting for the echo of the distant shore of a whole New World. One day, from the shores of a new world, we'll gaze at the sea that took us there. And its waves will be stars."
Thank you.
Notes
* Fernando Pessoa, poet, Mar Português, verses 1-2, 1934.
** Rui Borges, Kepler outreach team and entrepreneur, We are at the Prow of the Whole.
No comments:
Post a Comment