We hear the crack of a bullwhip because its tip is moving faster than the speed of sound, creating a shock wave, a small sonic boom. A thunderclap ha… - Carl Sagan

" "

We hear the crack of a bullwhip because its tip is moving faster than the speed of sound, creating a shock wave, a small sonic boom. A thunderclap has a similar origin. It was once thought that airplanes could not travel faster than sound. Today supersonic flight is commonplace. But the light barrier is different from the sound barrier. It is not merely an engineering problem like the one the supersonic airplane solves. It is a fundamental law of Nature, as basic as gravity. And there are no phenomena in our experience — like the crack of the bullwhip or the clap of thunder for sound — to suggest the possibility of traveling in a vacuum faster than light. On the contrary, there is an extremely wide range of experience — with nuclear accelerators and atomic clocks, for example — in precise quantitative agreement with special relativity.

English
Collect this quote

About Carl Sagan

Carl Edward Sagan (9 November 1934 – 20 December 1996) was an American astronomer, planetary scientist, cosmologist, astrophysicist, astrobiologist, author, and science communicator. His best known scientific contribution is research on extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation. Sagan assembled the first physical messages sent into space, the Pioneer plaque and the Voyager Golden Record, universal messages that could potentially be understood by any extraterrestrial intelligence that might find them. Sagan argued the hypothesis, accepted since, that the high surface temperatures of Venus can be attributed to, and calculated using, the greenhouse effect. He testified to the US Congress in 1985 that the greenhouse effect will change the earth's climate system.

Biography information from Wikiquote

Also Known As

Native Name: Carl Edward Sagan
Alternative Names: Sagan Carl E. Sagan Carl E Sagan C. E. Sagan C.E. Sagan C E Sagan C. Sagan C Sagan Sagan C Sagan C. Sagan C. E. Sagan CE

Limited Time Offer

Premium members can get their quote collection automatically imported into their Quotewise collections.

Related quotes. More quotes will automatically load as you scroll down, or you can use the load more buttons.

Additional quotes by Carl Sagan

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 key 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.

"After misapprehended natural events and hoaxes and psychological aberrations are removed from the data set, is there any residue of very credible but extremely bizarre cases, especially ones supported by physical evidence? Is there a "signal" hiding in all that noise? In my view, no signal has been detected. There are reliably reported cases that are unexotic, and exotic cases that are unreliable. There are no cases - despite well over a million UFO reports since 1947 - in which something so strange that it could only be an extraterrestrial spacecraft is reported so reliably that misapprehension, hoax, or hallucination can be reliably excluded."

PREMIUM FEATURE

Advanced Search Filters

Filter search results by source, date, and more with our premium search tools.

From the point of view of a mayfly, human beings are stolid, boring, almost entirely immovable, offering hardly a hint that they ever do anything. From the point of view of a star, a human being is a tiny flash, one of billions of brief lives flickering tenuously on the surface of a strangely cold, anomalously solid, exotically remote sphere of silicate and iron.

Loading...