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Sometime in the summer of 1786 the fifty-year-old John Adams, graduate of Harvard University, man of science and future second President of the United States, turned up one morning uninvited at The Grove. He was shown round all Herschel’s new telescopes, and they embarked on an impassioned discussion of the…
Ballooning produced a new, and wholly unexpected, vision of the earth. It had been imagined that it would reveal the secrets of the heavens above, but in fact it showed the secrets of the world beneath. The early aeronauts suddenly saw the earth as a giant organism, mysteriously patterned and unfolding, like a living…
It is possible to measure how far away from us each galaxy is. How? How, for that matter, do we know how far away anything in the universe is? For nearby stars the best method uses something called 'parallax'. Hold your finger up in front of your face and look at it with your left eye closed. Now open your left eye…
Newton wasn't the first person to make a rainbow with a prism. Other people had already got the same result. But many of them thought the prism somehow 'coloured' the white light, like adding a dye. Newton's idea was quite different. He thought that white light was a mixture of all the colours, and the prism was just…
If you want to see a rainbow you ' have to have the sun behind you when you look at a rainstorm. Each raindrop is more like a little ball than a prism, and light behaves differently when it Sits a ball from how it behaves when it hits a prism. The difference is that the far side of I raindrop acts as a tiny mirror…
The mathematician Freeman Dyson, of the Institute for Advanced Study, offers a scheme in which the planet Jupiter is broken down piece by piece, transported to the distance of the Earth from the Sun, and reconstructed into a spherical shell – a swarm of individual fragments revolving about the Sun. The advantage of…
There is a place with four suns in the sky – red, white, blue, and yellow; two of them are so close together that they touch, and star-stuff flows between them. I know of a world with a million moons. I know of a sun the size of the Earth – and made of diamond. There are atomic nuclei a mile across that rotate thirty…
It is possible to speculate on the very distant future of advanced civilizations. We can imagine such societies in excellent harmony with their environments, their biology, and the vagaries of their politics, so that they enjoy extraordinarily long lifetimes. Communications would long have been established with many…
On the title page of this chapter is shown the message. It is etched on a 6-inch by 9-inch gold-anodized aluminum plate, attached to the antenna support struts of Pioneer 10. The expected erosion rate in interstellar space is sufficiently small that this message should remain intact for hundreds of millions of years…
The earth's atmosphere is an imperfect window on the universe. Electromagnetic waves in the optical part of the spectrum (that is, waves longer than X rays and shorter than radio waves) penetrate to the surface of the earth only in a few narrow spectral bands. The widest of the transmitted bands corresponds roughly to…
Calculus is one of the most important parts of mathematics. It is fundamental to all of modern science. How could one part of mathematics be of such central importance? It is because calculus gives us the tools to study rates of change and motion. All analytical subjects, from biology to physics to chemistry to…
The way we discovered how species arise resembles the way astronomers discovered how stars “evolve” over time. Both processes occur too slowly for us to see them happening over our lifetime. But we can still understand how they work by finding snapshots of the process at different evolutionary stages and putting these…
Even if all brains were wired identically and all parents behaved in a cookie-cutter fashion, a great deal of current research would still be flawed (or, at best, preliminary). Most of the data we have are associative, not causal. Why is that a problem? Two things can be associated without one causing the other. For…
Man, being the servant and interpreter of Nature, can do and understand so much and so much only as he has observed in fact or in thought of the course of nature. Beyond this he neither knows anything nor can do anything.
We lay and looked up at the sky and the millions of stars that blazed in darkness. The night was so still that we could hear the buoy on the ledges out beyond the mouth of the bay. Once or twice a word spoken by someone on the far shore was carried across the clear air. A few lights burned in the cottages. Otherwise…
After an evening of talk, perhaps about the fringes of knowledge, or some new possibility of climbing inside the minds and senses of animals, we would go out on the lawn, where we took turns at an amusing little astronomical rite. We searched until we found, with or without glasses, the faint, heavenly spot of…
Water is so uniquely favorable to life as we know it, it is hard to imagine life without it. Where did it come from, this planetary wrap of fluid, this liquidy bower? A standard story is that the heat of the young Earth drove hydrogen and oxygen out of chemical combination in minerals like mica, and these atoms then…
And so they say that Uncle Paul knows any number of stories. He investigates, he observes for himself. When he walks in his garden he is seen now and then to stop before the hive, around which the bees are humming, or under the elder bush, from which the little flowers fall softly, like flakes of snow; sometimes he…
A more sophisticated consequence of omphalogical reasoning would be that stars whose distance from us is more than a few thousand light years must have been created with ready-made light beams stretching almost all the way to us - otherwise we wouldn't be able to see them until the distant future!
Sun's nature as revealed by modern science far more wonderful: no mere angels or gold coin, but an enormous sphere into which a million Earths could be packed, in the core of which the hidden nuclei of atoms are being jammed together, hydrogen transfigured into helium, the energy latent in hydrogen for billions of…