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Quotes by Astrophysicists
- Page 2
It is the responsibility of scientists never to suppress knowledge, no matter how awkward that knowledge is, no matter how it may bother those in power; we are not smart enough to decide which pieces of knowledge are permissible, and which are not. …
Carl Sagan
The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.
Carl Sagan
Winning the Origins Lottery Nontheistic models adhere to a central premise that humans arose by strictly natural unguided steps from a bacterial life-form that sprang into being 3.8 billion years ago. Famed evolutionary biologist Francisco Ayala, an advocate for the hypothesis that natural selection and mutations can efficiently generate distinctly different species, nevertheless calculated the probability that humans (or a similarly intelligent species) arose from single-celled organisms as a possibility so small (10-1,000,000) that it might as well be zero (roughly equivalent to the likelihood of winning the California lottery 150,000 consecutive times with the purchase of just one ticket each time).2 He and other evolutionary biologists agree that natural selection and mutations could have yielded any of a virtually infinite number of other outcomes. Astrophysicists Brandon Carter, John Barrow, and Frank Tipler produced an even smaller probability.
Hugh Ross
If everyone had the luxury to pursue a life of exactly what they love, we would all be ranked as visionary and brilliant. … If you got to spend every day of your life doing what you love, you can’t help but be the best in the world at that. And you get to smile every day for doing so. And you’ll be working at it almost to the exclusion of personal hygiene, and your friends are knocking on your door, saying, “Don’t you need a vacation?!,” and you don’t even know what the word “vacation” means because what you’re doing is what you want to do and a vacation from that is anything but a vacation — that’s the state of mind of somebody who’s doing what others might call visionary and brilliant.
Neil deGrasse Tyson
I find these comparisons particularly poignant: life versus death, hope versus fear. Space exploration and the highly mechanized destruction of people use similar technology and manufacturers, and similar human qualities of organization and daring. Can we not make the transition from automated aerospace killing to automated aerospace exploration of the solar system in which we live?
Carl Sagan
The dangers that we face are part of the process, now well underway, of the unification of the planet--in language, culture, science, and commerce. They are both driven by the identical technological advances--this critical and delicate time coincides with the widespread availability of nuclear weapons. At the present rate of change, it seems likely that in the period between now and 2061, the turning point for the human species will have been reached.If we survive until then, our passage to the next apparition of Halley's Comet should be comparatively easy. That perihelion passage will be in March 2134, when the comet will make an unusually close encounter with the Earth. It will come as close as 0.09AU or 14 million kilometers, less than half the distance of the 1910 encounter. It will then be brighter than the brightest star. If there are those to do the commemorating, the years 2061 and 2134 should be celebrated for the courage, intelligence, and common purpose of a species forced by urgent necessity to come to its senses.
Carl Sagan
Meanwhile the Cosmos is rich beyond measure: the total number of stars in the universe is greater than all the grains of sand on all the beaches of the planet Earth.
Carl Sagan
We will know which stars to visit. Our descendants will then skim the light years, the children of Thales and Aristarchus, Leonardo and Einstein.
Carl Sagan
If you ask people where they're from, they will typically say the name of the city where they were born, or perhaps the place on Earth's surface where they spent their formative years. Nothing wrong with that. But an astrochemically richer answer might be, "I hail from the explosive jetsam of a multitude of high-mass stars that died more than 5 billion years ago.
Neil deGrasse Tyson
The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.
Carl Sagan
Before we invented civilization our ancestors lived mainly in the open out under the sky. Before we devised artificial lights and atmospheric pollution and modern forms of nocturnal entertainment we watched the stars. There were practical calendar reasons of course but there was more to it than that. Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away.
Carl Sagan
The Apollo pictures of the whole Earth conveyed to multitudes something well known to astronomers: On the scale of the worlds - to say nothing of stars or galaxies - humans are inconsequential, a thin film of life on an obscure and solitary lump of rock and metal
Carl Sagan
The major religions on the Earth contradict each other left and right. You can't all be correct. And what if all of you are wrong? It's a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I'm not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they're called hypotheses, not inspiration and not revelation.
Carl Sagan
There is every reason to think that in the coming years Mars and its mysteries will become increasingly familiar to the inhabitants of the Planet Earth.
Carl Sagan
Whatever the reason we first mustered the _Apollo_ program, however mired it was in Cold War nationalism and the instruments of death, the inescapable recognition of the unity and fragility of the Earth is its clear and luminous dividend, the unexpected final gift of _Apollo_. What began in deadly competition has helped us to see that global cooperation is the essential precondition for our survival.Travel is broadening. It's time to hit the road again.
Carl Sagan
The hole in the ozone layer is a kind of skywriting. At first it seemed to spell out our continuing complacency before a witch's brew of deadly perils. But perhaps it really tells of a newfound talent to work together to protect the global environment.
Carl Sagan
When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there's only one kind. It uses about fifty fundamental biological building blocks, organic molecules.
Carl Sagan
Allow intelligent design into science textbooks, lecture halls, and laboratories, and the cost to the frontier of scientific discovery—the frontier that drives the economies of the future—would be incalculable. I don't want students who could make the next major breakthrough in renewable energy sources or space travel to have been taught that anything they don't understand, and that nobody yet understands, is divinely constructed and therefore beyond their intellectual capacity. The day that happens, Americans will just sit in awe of what we don't understand, while we watch the rest of the world boldly go where no mortal has gone before.
Neil deGrasse Tyson
Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? ... No other human institution comes close.
Carl Sagan
Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of magic.
Carl Sagan
In addition to Ameslan, chimpanzees and other nonhuman primates are being taught a variety of other gestural languages. And it is just this transition from tongue to hand that has permitted humans to regain the ability-lost, according to Josephus, since Eden-to communicate with the animals.
Carl Sagan
The strength of the familiar electromagnetic force between two electrons, for example, is expressed in physics in terms of a constant known as the fine structure constant. The value of this constant, almost exactly 1/137, has puzzled many generations of physicists. A joke made about the famous English physicist Paul Dirac (1902-1984), one of the founders of quantum mechanics, says that upon arrival to heaven he was allowed to ask God one question. His question was: "Why 1/137?
Mario Livio
Science cuts two ways, of course; its products can be used for both good and evil. But there's no turning back from science. The early warnings about technological dangers also come from science.
Carl Sagan
Not enough books focus on how a culture responds to radically new ideas or discovery. Especially in the biography genre, they tend to focus on all the sordid details in the life of the person who made the discovery. I find this path to be voyeuristic but not enlightening. Instead, I ask, After evolution was discovered, how did religion and society respond? After cities were electrified, how did daily life change? After the airplane could fly from one country to another, how did commerce or warfare change? After we walked on the Moon, how differently did we view Earth? My larger understanding of people, places and things derives primarily from stories surrounding questions such as those.
Neil deGrasse Tyson
The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.
Carl Sagan
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.
Carl Sagan
I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking.The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.
Carl Sagan
Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.
Carl Sagan
Given enough time, even evolution evolves.
Eric Chaisson
Evolution, energy, and ethics are the core elements that will guide us along the challenging path toward the Life Era: the first - evolution - because a good understanding of our universal roots and of our place in the cosmic scheme of things will help us create a feasible future course; the second - energy - because our fate will bear strongly on the ways that humankind learns to use energy efficiently and safely; and the third - ethics - because global citizenship and a planetary society are crucial factors in the survival of our species.
Eric Chaisson
One of the great commandments of science is, 'Mistrust arguments from authority'. (Scientists, being primates, and thus given to dominance hierarchies, of course do not always follow this commandment.)
Carl Sagan
Civilization is a product of the cerebral cortex.
Carl Sagan
The secrets of evolution, are time and death. There's an unbroken thread that stretches from those first cells to us.
Carl Sagan
How thoroughly the chimps and bonobos have erased the list of purported human distinctions!-self-awareness, language, ideas and their association, reason, trade, play, choice, courage, love and altruism, laughter, concealed ovulation, kissing, face-to-face sex, female orgasm, division of labor, cannibalism, art, music, politics, and featherless bipedalism, besides tool using, tool making, and much else. Philosophers and scientists confidently offer up traits said to be uniquely human, and the apes casually knock them down--toppling the pretension that humans constitute some sort of biological aristocracy among the beings of Earth. Instead, we are more like the nouveau riche, incompletely accommodated to our recent exalted state, insecure about who we are, and trying to put as much distance as possible between us and our humble origins. It's as if our nearest relatives, by their very existence, refute all our explanations and justifications. So as counterweights to human arrogance and pride, it is good for us that there are still apes on Earth.
Carl Sagan
All the explanations proposed seem to beonly partly satisfactory. They range from massive climatic change to mammalian predation to the extinction of a plant with apparent laxative properties, in which case the dinosaurs died of constipation.
Carl Sagan
at least some paleontologists believe that the demiseof the dinosaurs was accelerated by nocturnal predation on reptilian eggs by the early mammals. Two chicken eggs for breakfast may be all-at least on the surface-that is left of this ancient mammalian cuisine.
Carl Sagan
So far as I know, childbirth is generally painful in only one of the millions of species on Earth: human beings. This must be a consequence of the recent and continuing increase in cranial volume... Childbirth is painful because the evolution of the human skull has been spectacularly fast and recent.
Carl Sagan
Pliny suggested that the ostrich, then newly discovered, was the result of a cross between a giraffe and a gnat. (It would, I suppose, have to be a female giraffe and a male gnat.) In practice there must be many such crosses which have not beenattempted because of a certain understandable lack of motivation.
Carl Sagan
It is very difficult to evolve by altering the deep fabric of life; any change there is likely to be lethal. But fundamental change can be accomplished by the addition of new systems on top of old ones…Thus evolution by addition and the functional preservation of the preexisting structure must occur for one of two reasons-either the old function is required as well as the new one, or there is no way of bypassing the old system that is consistent with survival.
Carl Sagan
The time scale for evolutionary or genetic change is very long. A characteristic period for the emergence of one advanced species from another is perhaps a hundred thousand years; and very often the difference in behavior between closely related species -say, lions and tigers- do not seem very great... But today we do not have ten million years to wait for the next advance. We live in a time when our world is changing at an unprecedented rate. While the changes are largely of our own making, they cannot be ignored. We must adjust and adapt and control, or we perish.
Carl Sagan
Our probable ancestors, Homo erectus and Homo habilis -now extinct- are classified as of the same genus (Homo) but of different species, although no one (at least lately) has attempted the appropriate experiments to see if crosses of them with us would produce fertile offspring.
Carl Sagan
Curiosity and the urge to solve problems are theemotional hallmarks of our species
Carl Sagan
For their surface area, insects weigh very little. A beetle, falling from a high altitude, quickly achieves terminal velocity: air resistance prevents it from falling very fast, and, after alighting on the ground, it will walk away, apparently none the worse for the experience… In contrast, human beings are characteristically maimed or killed by any fall of more than a few dozen feet: because of our size, we weigh too much for our surface area.
Carl Sagan
And despite the insignificance of the instant we have so far occupied in cosmic time, it is clear that what happens on and near Earth at the beginning of thesecond cosmic year will depend very much on the scientific wisdom and the distinctly human sensitivity of mankind.
Carl Sagan
The sleeping style of each organism is exquisitelyadapted to the ecology of the animal. It is conceivable that animals who are too stupid to be quiet on their own initiative are, during periods of high risk, immobilized by the implacable arm of sleep.
Carl Sagan
Washburn has reported that infant baboons and other young primates appear to be born with only three inborn fears -of falling, snakes, and the dark-corresponding respectively to the dangers posed byNewtonian gravitation to tree-dwellers, by our ancient enemies the reptiles, and by mammalian nocturnal predators, which must have been particularly terrifying for the visually oriented primates.
Carl Sagan
Not that chance dominated events in the early Solar System, for scientific determinism was also functioning. But chance is an essential factor in all evolutionary events, and the birth and development of our planetary system were not exceptions.
Eric Chaisson
Perhaps if one less dragonfly had drowned in the Carboniferous swamps, the intelligent organisms on our planet today would have feathers and teach their young in rookeries. The pattern of evolutionary causality is a web of astonishing complexity; the incompleteness of our understanding humbles us.
Carl Sagan
There were many women in the Soviet scientific community, proportionately more so than in the United States. But they tended to occupy menial middle-level positions, and male Soviet scientists, like their American counterparts, were puzzled about a pretty woman with evident scientific competence who forcefully expressed her views.
Carl Sagan
An atheist is someone who is certain that God doesn't exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence.
Carl Sagan
I am not religious in any sense; in fact, I consider myself an atheist.
Subrahmanijan Chandrasekhar
The world is so exquisite, with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little goodevidence.
Carl Sagan
I'd ask [God] why he keeps trying to kill us all with disease, pestilence, and natural disasters. I'd ask why 99% of all species there ever were are now extinct -- if God works in mysterious ways, that way is mysteriously genocidal.
Neil deGrasse Tyson
An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to uptime causes, we would have to know a great deal more about the Universe than we do now to be sure that no such God exists. To be certain of the existence of God and you be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed.
Carl Sagan
For thousands of years humans were oppressed - as some of us still are - by the notion that the universe is a marionette whose strings are pulled by a god or gods, unseen and inscrutable.
Carl Sagan
I have a foreboding of an America in my children's or grandchildren's time -- when the United States is a service and information economy; when nearly all the manufacturing industries have slipped away to other countries; when awesome technological powers are in the hands of a very few, and no one representing the public interest can even grasp the issues; when the people have lost the ability to set their own agendas or knowledgeably question those in authority; when, clutching our crystals and nervously consulting our horoscopes, our critical faculties in decline, unable to distinguish between what feels good and what's true, we slide, almost without noticing, back into superstition and darkness...The dumbing down of American is most evident in the slow decay of substantive content in the enormously influential media, the 30 second sound bites (now down to 10 seconds or less), lowest common denominator programming, credulous presentations on pseudoscience and superstition, but especially a kind of celebration of ignorance
Carl Sagan
...two chimpanzees were observed maltreating a chicken: One would extend some food to the fowl, encouraging it to approach; whereupon the other would thrust at it with a piece of wire it had concealed behind its back. The chicken would retreat but soon allow itself to approach once again--and be beaten once again. Here is a fine combination of behavior sometimes thought to be uniquely human: cooperation, planning a future course of action, deception and cruelty.
Carl Sagan
Much of the difficulty in attempting to restructure American and other societies arises form this resistance by groups with vested interests in the status quo. Significant change might require those who are now high in the hierarchy to move downward many steps. This seems to them undesirable and its resisted.
Carl Sagan
Perhaps the most striking aspect of this entire subject is that there are nonhuman primates so close to the edge of language, so willing to learn, so entirely competent in its use and inventive in its application once the language is taught. But this raises a curious question: Why are they all on the edge? Why are there no nonhuman primates with an existing complex gestural language? One possible answer, it seems to me, is that humans have systematically exterminated those other primates who displayed signs of intelligence.
Carl Sagan
Unlike what you may be told in other sectors of life, when observing the universe, size does matter, which often leads to polite ‘telescope envy’ at gatherings of amateur astronomers.
Neil deGrasse Tyson
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