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When the movement of the comets is considered and we reflect on the laws of gravity, it will be readily perceived that their approach to Earth might there cause the most woeful events, bring back the deluge, or make it perish in a deluge of fire, shatter it into small dust, or at least turn it from its orbit, drive…
When they [radio astronomers] grew weary at their electronic listening posts. When their eyes grew dim with looking at unrevealing dials and studying uneventful graphs, they could step outside their concrete cells and renew their dull spirits in communion with the giant mechanism they commanded, the silent, sensing…
Every 12 years Jupiter returns to the same position in the sky; every 370 days it disappears in the fire of the Sun in the evening to the west, 30 days later it reappears in the morning to the east...
The astronomer is, in some measure, independent of his fellow astronomer; he can wait in his observatory till the star he wishes to observe comes to his meridian; but the meteorologist has his observations bounded by a very limited horizon, and can do little without the aid of numerous observers furnishing him…
A star is drawing on some vast reservoir of energy by means unknown to us. This reservoir can scarcely be other than the subatomic energy which, it is known exists abundantly in all matter; we sometimes dream that man will one day learn how to release it and use it for his service. The store is well nigh…
The zodiacal light is caused by sunlight reflecting from meteoric dust that orbits the sun in the plane of the solar system, remnants of the vast nebula of dust and gas out of which the solar system was born more than four billion years ago. Like the planets, this diffuse stream of particles reflects light, although…
Almost 1000 years ago, Chinese astronomers observed a new star visible in the daytime sky, which they called a “guest star.” This supernova created what we now observe telescopically as the Crab Nebula. It is interesting that nowhere in Western Europe was this transient object recorded. Church dogma at the time…
After a duration of a thousand years, the power of astrology broke down when, with Copernicus, Kepler, and Galileo, the progress of astronomy overthrew the false hypothesis upon which the entire structure rested, namely the geocentric system of the universe. The fact that the earth revolves in space intervened to…
I myself consider that gravity is merely a certain natural inclination with which parts are imbued by the architect of all things for gathering themselves together into a unity and completeness by assembling into the form of a globe. It is easy to believe that the Sun, Moon and other luminaries among the wandering…
That the machine of Heaven is not a hard and impervious body full of various real spheres, as up to now has been believed by most people. It will be proved that it extends everywhere, most fluid and simple, and nowhere presents obstacles as was formerly held, the circuits of the Planets being wholly free and without…
Copernicus, who rightly did condemn This eldest systeme, form'd a wiser scheme; In which he leaves the Sun at Rest, and rolls The Orb Terrestial on its proper Poles; Which makes the Night and Day by this Career, And by its slow and crooked Course the Year. The famous Dane, who oft the Modern guides, To Earth and Sun…
All the knowledge we possess of external objects is founded upon experience, which furnishes facts; and the comparison of these facts establishes relations, from which induction, the intuitive belief that like causes will produce like effects, leads to general laws. Thus, experience teaches that bodies fall at the…
1.How faint are the farthest objects? The Hubble observations detected objects as faint as 30th magnitude. The faintest objects the human eye can see are at sixth magnitude. Ground-based telescopes also can detect 30th-magnitude objects. Those objects, however, are so dim they are lost in the glare of brighter, nearby…
Here we go again, one of the epic documents of our time, the Hubble Ultra Deep Field (UDF) photograph, the deepest look into space ever. A random part of the sky, so small it could be covered by a pinhead held at arm's length. A part of the sky -- as NASA says -- that you'd see looking through an eight-foot-long soda…
The young John Keats remembered an organised game at his school in Enfield, in which all the boys whirled round the playground in a huge choreographed dance, trying to imitate the entire solar system, including all the known moons (to which Herschel had by then added considerably). Unlike Newton’s perfect brassy…
Already in a paper of 1802 Herschel considered the idea that ‘deep space’ must also imply ‘deep time’. He wrote in his Preface: A telescope with a power of penetrating into space, like my 40 foot one, has also, as it may be called, a power of penetrating into time past … [from a remote nebula] the rays of light which…
This method of viewing the galaxies (‘to continue the simile I have borrowed from the vegetable kingdom’) presented the entire universe in a new kind of light, with the most radical implications. ‘The heavens are now seen to resemble a luxuriant garden which contains the greatest variety of productions, in different…
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…
Pioneer 10 is the first interstellar spacecraft launched by mankind. It was also the fastest spacecraft launched, to the date of its departure. But it will take eighty thousand years for Pioneer 10 to reach the distance of the nearest star. Because space is so empty, it will never enter another Solar System. The…
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…