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As to your first query, it seems to me that if the matter of our sun and planets and all the matter of the universe were evenly scattered throughout all the heavens, and every particle had an innate gravity toward all the rest, and the whole space throughout which this matter was scattered was but finite, the matter…
On certain small planets, drenched with light and heat from a near or a great sun, evolution took a very different course from that with which we are familiar. The vegetable and animal functions were not separated into distinct organic types. Every organism was at once animal and vegetable. Many species, of course…
Six years ago, in the distant Trisolaran stellar system, Trisolaris accelerated two hydrogen nuclei to near the speed of light and shot them toward the solar system. These two hydrogen nuclei, or protons, arrived at the solar system two years ago, then reached the Earth.
But why should comets become more likely to hit us every million years? Here we launch ourselves into deep speculation. It has been suggested that the sun has a sister star, and the two orbit each other with a periodicity of about 26 million years. This hypothetical binary partner, which has never been seen but which…
Imagine a spaceship full of sleeping explorers, deep-frozen would-be colonists of some distant world. Perhaps the ship is on a forlorn mission to save the species before an unstoppable comet, like the one that killed the dinosaurs, hits the home planet. The voyagers go into the deep-freeze soberly reckoning the odds…
The basic idea of Astrochicken is that the spacecraft will be small and quick. I do not believe that a fruitful future for space science lies along the path we are now following, with space missions growing larger and larger and fewer and fewer and slower and slower as the decades go by. I propose a radical step in…
Since I have had to pay college tuition for five daughters, I have chosen to play the role of preacher. I preach to all who will listen the gospel of manifest destiny. The destiny which I am preaching is not the expansion of a single nation or of a single species, but the spreading out of life in all its multifarious…
As all regions below are replenished with living creatures, (not only the Earth with Beasts, and Sea with Fishes and the air with Fowls and Insects, but also standing waters, vineger, the bodies and blood of Animals and other juices {49} with innumerable living creatures too small to be seen without the help of…
It happened three times in the past that theoretical astronomers invented a new planet on the basis of indirect and circumstantial evidence. The first time was in 1845 when Adams and Leverrier independently deduced the existence of the planet Neptune from the perturbations which it had produced in the motion of…
Piet Hut, another Dutch astronomer fifty years younger than Jan Oort, decided to take seriously the possibility that comet showers are periodic. If they are periodic, the theory that they are caused by the random passing-by of alien stars cannot be right. If showers are periodic, they must be explained by a different…
To understand why comet showers occur, we go back to the Oort Cloud. The theory of comet showers was worked out by Jack Hills, an American physicist now at Los Alamos. He realized that the movements of the comets in the Oort Cloud are not entirely random. Comets in the cloud are generally moving in random directions…
"Take all the planets in a star system and dismantle them," she explains. "Turn them into dust – structured nanocomp, powered by heat exchangers, spread in concentric orbits around the central star. The inner orbitals run close to the melting point of iron, the outer ones are cold as liquid nitrogen, and each layer…
Mars is just dumb mass at the bottom of a gravity well; there isn't even a biosphere there. They should be working on uploading and solving the nanoassembly conformational problem instead. Then we could turn all the available dumb matter into computronium and use it for processing our thoughts. Long-term, it's the…
"There are a million points of light in the universe traveling a million miles an hour away from us, yet they are so far away they appear to be standing still." "Estimate for # of planets in visible universe: 10^25, which = # molecules in a cup of water" Robert Garisto, PRL "I'm is Juliet Retenford and my favorite…
The material factors which ultimately limit the expansion of a technically advanced species are the supply of matter and the supply of energy. At present the material resources being exploited by the human species are roughly limited to the biosphere of the earth, a mass of the order of 5 X 10^19 grams. Our present…
As to your reasoning of the inconvenience that a centre would become further removed from another centre than from the circumference of his own globe, though centres are of the same species while the centre and circumference are of contrary nature and should therefore be furthest removed from one another, I reply as…
Elpino. Why then do we not see the other bright bodies which are earths circling around the bright bodies which are suns? For beyond these we can detect no motion whatever; and why do all other mundane bodies (except those known as comets) appear always in the same order and at the same distance? Philotheo. The reason…
Imagine the history of the galaxy with respect to extraterrestrial intelligence. Very early there were only first generation stars, no heavy metals and therefore no possibility of life, much less intelligence. That's Stage One. In Stage Two planets with heavy metals form from the starstuff processed in the previous…
Geoff Marcy, the University of California at Berkeley astronomer who has found scores of exoplanets, and who has diligently searched for signs of anything artificial in the data, says the silence is significant: “If our Milky Way Galaxy were teeming with thousands of advanced civilizations, as depicted in…
Behind every man now alive stand thirty ghosts, for that is the ratio by which the dead outnumber the living. Since the dawn of time, roughly a hundred billion human beings have walked the planet Earth. Now this is an interesting number, for by a curious coincidence there are approximately a hundred billion stars in…